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id="toc-Cephalochordata:_Lancelets" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Cephalochordata:_Lancelets"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Cephalochordata: Lancelets</span> </div> </a> <ul id="toc-Cephalochordata:_Lancelets-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Tunicata_(Urochordata)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Tunicata_(Urochordata)"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Tunicata (Urochordata)</span> </div> </a> <ul id="toc-Tunicata_(Urochordata)-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Craniata_(Vertebrata)" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Craniata_(Vertebrata)"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Craniata (Vertebrata)</span> </div> </a> <ul id="toc-Craniata_(Vertebrata)-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Phylogeny" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Phylogeny"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Phylogeny</span> </div> </a> <button aria-controls="toc-Phylogeny-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Phylogeny subsection</span> </button> <ul id="toc-Phylogeny-sublist" class="vector-toc-list"> <li id="toc-Overview" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Overview"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Overview</span> </div> </a> <ul id="toc-Overview-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Cladogram" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Cladogram"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Cladogram</span> </div> </a> <ul id="toc-Cladogram-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Closest_nonchordate_relatives" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Closest_nonchordate_relatives"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Closest nonchordate relatives</span> </div> </a> <button aria-controls="toc-Closest_nonchordate_relatives-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Closest nonchordate relatives subsection</span> </button> <ul id="toc-Closest_nonchordate_relatives-sublist" class="vector-toc-list"> <li id="toc-Hemichordates" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Hemichordates"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1</span> <span>Hemichordates</span> </div> </a> <ul id="toc-Hemichordates-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Echinoderms" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Echinoderms"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.2</span> <span>Echinoderms</span> </div> </a> <ul id="toc-Echinoderms-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Table of Contents" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Chordate</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 149 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-149" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">149 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Rugkoorddiere" title="Rugkoorddiere – Afrikaans" lang="af" hreflang="af" data-title="Rugkoorddiere" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-als mw-list-item"><a href="https://als.wikipedia.org/wiki/Chordatiere" title="Chordatiere – Alemannic" lang="gsw" hreflang="gsw" data-title="Chordatiere" data-language-autonym="Alemannisch" data-language-local-name="Alemannic" class="interlanguage-link-target"><span>Alemannisch</span></a></li><li class="interlanguage-link interwiki-am mw-list-item"><a href="https://am.wikipedia.org/wiki/%E1%8A%A0%E1%88%9D%E1%8B%B0%E1%88%B5%E1%8C%8C" title="አምደስጌ – Amharic" lang="am" hreflang="am" data-title="አምደስጌ" data-language-autonym="አማርኛ" data-language-local-name="Amharic" class="interlanguage-link-target"><span>አማርኛ</span></a></li><li class="interlanguage-link interwiki-smn mw-list-item"><a href="https://smn.wikipedia.org/wiki/Savosuon%C3%A2siih" title="Savosuonâsiih – Inari Sami" lang="smn" hreflang="smn" data-title="Savosuonâsiih" data-language-autonym="Anarâškielâ" data-language-local-name="Inari Sami" class="interlanguage-link-target"><span>Anarâškielâ</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%AD%D8%A8%D9%84%D9%8A%D8%A7%D8%AA" title="حبليات – Arabic" lang="ar" hreflang="ar" data-title="حبليات" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Chordata" title="Chordata – Aragonese" lang="an" hreflang="an" data-title="Chordata" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-frp mw-list-item"><a href="https://frp.wikipedia.org/wiki/Cord%C3%A2s" title="Cordâs – Arpitan" lang="frp" hreflang="frp" data-title="Cordâs" data-language-autonym="Arpetan" data-language-local-name="Arpitan" class="interlanguage-link-target"><span>Arpetan</span></a></li><li class="interlanguage-link interwiki-as mw-list-item"><a href="https://as.wikipedia.org/wiki/%E0%A6%95%27%E0%A7%B0%E0%A6%A1%E0%A6%BE%E0%A6%9F%E0%A6%BE" title="ক'ৰডাটা – Assamese" lang="as" hreflang="as" data-title="ক'ৰডাটা" data-language-autonym="অসমীয়া" data-language-local-name="Assamese" class="interlanguage-link-target"><span>অসমীয়া</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Chordata" title="Chordata – Asturian" lang="ast" hreflang="ast" data-title="Chordata" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-awa mw-list-item"><a href="https://awa.wikipedia.org/wiki/%E0%A4%95%E0%A4%B0%E0%A5%8D%E0%A4%A1%E0%A5%87%E0%A4%9F%E0%A4%BE" title="कर्डेटा – Awadhi" lang="awa" hreflang="awa" data-title="कर्डेटा" data-language-autonym="अवधी" data-language-local-name="Awadhi" class="interlanguage-link-target"><span>अवधी</span></a></li><li class="interlanguage-link interwiki-gn mw-list-item"><a href="https://gn.wikipedia.org/wiki/Mymba_s%C3%A3_atukup%C3%A9pe" title="Mymba sã atukupépe – Guarani" lang="gn" hreflang="gn" data-title="Mymba sã atukupépe" data-language-autonym="Avañe'ẽ" data-language-local-name="Guarani" class="interlanguage-link-target"><span>Avañe'ẽ</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Xordal%C4%B1lar" title="Xordalılar – Azerbaijani" lang="az" hreflang="az" data-title="Xordalılar" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%D8%AE%D9%88%D8%B1%D8%AF%D8%A7%D9%84%DB%8C%D9%84%D8%A7%D8%B1" title="خوردالیلار – South Azerbaijani" lang="azb" hreflang="azb" data-title="خوردالیلار" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-ban mw-list-item"><a href="https://ban.wikipedia.org/wiki/Chordata" title="Chordata – Balinese" lang="ban" hreflang="ban" data-title="Chordata" data-language-autonym="Basa Bali" data-language-local-name="Balinese" class="interlanguage-link-target"><span>Basa Bali</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%95%E0%A6%B0%E0%A7%8D%E0%A6%A1%E0%A6%BE%E0%A6%9F%E0%A6%BE" title="কর্ডাটা – Bangla" lang="bn" hreflang="bn" data-title="কর্ডাটা" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-zh-min-nan mw-list-item"><a href="https://zh-min-nan.wikipedia.org/wiki/Chek-soh_t%C5%8Dng-bu%CC%8Dt" title="Chek-soh tōng-bu̍t – Minnan" lang="nan" hreflang="nan" data-title="Chek-soh tōng-bu̍t" data-language-autonym="閩南語 / Bân-lâm-gú" data-language-local-name="Minnan" class="interlanguage-link-target"><span>閩南語 / Bân-lâm-gú</span></a></li><li class="interlanguage-link interwiki-ba mw-list-item"><a href="https://ba.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%BB%D1%8B%D0%BB%D0%B0%D1%80" title="Хордалылар – Bashkir" lang="ba" hreflang="ba" data-title="Хордалылар" data-language-autonym="Башҡортса" data-language-local-name="Bashkir" class="interlanguage-link-target"><span>Башҡортса</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%B2%D1%8B%D1%8F" title="Хордавыя – Belarusian" lang="be" hreflang="be" data-title="Хордавыя" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%B2%D1%8B%D1%8F" title="Хордавыя – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Хордавыя" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bh mw-list-item"><a href="https://bh.wikipedia.org/wiki/%E0%A4%95%E0%A4%BE%E0%A4%B0%E0%A5%8D%E0%A4%A1%E0%A5%87%E0%A4%9F" title="कार्डेट – Bhojpuri" lang="bh" hreflang="bh" data-title="कार्डेट" data-language-autonym="भोजपुरी" data-language-local-name="Bhojpuri" class="interlanguage-link-target"><span>भोजपुरी</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%BE%D0%B2%D0%B8" title="Хордови – Bulgarian" lang="bg" hreflang="bg" data-title="Хордови" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%A6%E0%BE%92%E0%BD%A3%E0%BC%8B%E0%BD%90%E0%BD%82%E0%BC%8B%E0%BD%A6%E0%BE%B2%E0%BD%BC%E0%BD%82%E0%BC%8B%E0%BD%86%E0%BD%82%E0%BD%A6%E0%BC%8B" title="སྒལ་ཐག་སྲོག་ཆགས་ – Tibetan" lang="bo" hreflang="bo" data-title="སྒལ་ཐག་སྲོག་ཆགས་" data-language-autonym="བོད་ཡིག" data-language-local-name="Tibetan" class="interlanguage-link-target"><span>བོད་ཡིག</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Hordati" title="Hordati – Bosnian" lang="bs" hreflang="bs" data-title="Hordati" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Kordeg" title="Kordeg – Breton" lang="br" hreflang="br" data-title="Kordeg" data-language-autonym="Brezhoneg" data-language-local-name="Breton" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-bxr mw-list-item"><a href="https://bxr.wikipedia.org/wiki/%D0%A5%D2%AF%D0%B1%D1%88%D1%8D%D1%82%D1%8D%D0%BD" title="Хүбшэтэн – Russia Buriat" lang="bxr" hreflang="bxr" data-title="Хүбшэтэн" data-language-autonym="Буряад" data-language-local-name="Russia Buriat" class="interlanguage-link-target"><span>Буряад</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Cordats" title="Cordats – Catalan" lang="ca" hreflang="ca" data-title="Cordats" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%A5%D0%B8%D1%80%D0%BB%D3%B3%D0%BB%D0%BB%D0%B8" title="Хирлӳлли – Chuvash" lang="cv" hreflang="cv" data-title="Хирлӳлли" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-ceb mw-list-item"><a href="https://ceb.wikipedia.org/wiki/Maybukobuko" title="Maybukobuko – Cebuano" lang="ceb" hreflang="ceb" data-title="Maybukobuko" data-language-autonym="Cebuano" data-language-local-name="Cebuano" class="interlanguage-link-target"><span>Cebuano</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Strunatci" title="Strunatci – Czech" lang="cs" hreflang="cs" data-title="Strunatci" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Cordog" title="Cordog – Welsh" lang="cy" hreflang="cy" data-title="Cordog" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Chordater" title="Chordater – Danish" lang="da" hreflang="da" data-title="Chordater" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-ary mw-list-item"><a href="https://ary.wikipedia.org/wiki/%D8%AD%D8%A8%D9%84%D9%8A%D8%A7%D8%AA" title="حبليات – Moroccan Arabic" lang="ary" hreflang="ary" data-title="حبليات" data-language-autonym="الدارجة" data-language-local-name="Moroccan Arabic" class="interlanguage-link-target"><span>الدارجة</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Chordatiere" title="Chordatiere – German" lang="de" hreflang="de" data-title="Chordatiere" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-nv mw-list-item"><a href="https://nv.wikipedia.org/wiki/B%C3%AD%C3%ADgh%C4%85%CC%81%C4%85%CC%81sts%CA%BC%C7%AB%C7%ABd_Dah%C3%B3l%C3%B3n%C3%ADg%C3%AD%C3%AD" title="Bííghą́ą́stsʼǫǫd Dahólónígíí – Navajo" lang="nv" hreflang="nv" data-title="Bííghą́ą́stsʼǫǫd Dahólónígíí" data-language-autonym="Diné bizaad" data-language-local-name="Navajo" class="interlanguage-link-target"><span>Diné bizaad</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Keelikloomad" title="Keelikloomad – Estonian" lang="et" hreflang="et" data-title="Keelikloomad" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%A7%CE%BF%CF%81%CE%B4%CF%89%CF%84%CE%AC" title="Χορδωτά – Greek" lang="el" hreflang="el" data-title="Χορδωτά" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Chordata" title="Chordata – Spanish" lang="es" hreflang="es" data-title="Chordata" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/%C4%A4orduloj" title="Ĥorduloj – Esperanto" lang="eo" hreflang="eo" data-title="Ĥorduloj" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-ext mw-list-item"><a href="https://ext.wikipedia.org/wiki/Chordata" title="Chordata – Extremaduran" lang="ext" hreflang="ext" data-title="Chordata" data-language-autonym="Estremeñu" data-language-local-name="Extremaduran" class="interlanguage-link-target"><span>Estremeñu</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Kordatu" title="Kordatu – Basque" lang="eu" hreflang="eu" data-title="Kordatu" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B7%D9%86%D8%A7%D8%A8%D8%AF%D8%A7%D8%B1%D8%A7%D9%86" title="طنابداران – Persian" lang="fa" hreflang="fa" data-title="طنابداران" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-hif mw-list-item"><a href="https://hif.wikipedia.org/wiki/Chordata" title="Chordata – Fiji Hindi" lang="hif" hreflang="hif" data-title="Chordata" data-language-autonym="Fiji Hindi" data-language-local-name="Fiji Hindi" class="interlanguage-link-target"><span>Fiji Hindi</span></a></li><li class="interlanguage-link interwiki-fo mw-list-item"><a href="https://fo.wikipedia.org/wiki/Chordata" title="Chordata – Faroese" lang="fo" hreflang="fo" data-title="Chordata" data-language-autonym="Føroyskt" data-language-local-name="Faroese" class="interlanguage-link-target"><span>Føroyskt</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Chordata" title="Chordata – French" lang="fr" hreflang="fr" data-title="Chordata" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-fy mw-list-item"><a href="https://fy.wikipedia.org/wiki/R%C3%AAchstringdieren" title="Rêchstringdieren – Western Frisian" lang="fy" hreflang="fy" data-title="Rêchstringdieren" data-language-autonym="Frysk" data-language-local-name="Western Frisian" class="interlanguage-link-target"><span>Frysk</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Chordata" title="Chordata – Irish" lang="ga" hreflang="ga" data-title="Chordata" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gv mw-list-item"><a href="https://gv.wikipedia.org/wiki/Chordata" title="Chordata – Manx" lang="gv" hreflang="gv" data-title="Chordata" data-language-autonym="Gaelg" data-language-local-name="Manx" class="interlanguage-link-target"><span>Gaelg</span></a></li><li class="interlanguage-link interwiki-gd mw-list-item"><a href="https://gd.wikipedia.org/wiki/Chordata" title="Chordata – Scottish Gaelic" lang="gd" hreflang="gd" data-title="Chordata" data-language-autonym="Gàidhlig" data-language-local-name="Scottish Gaelic" class="interlanguage-link-target"><span>Gàidhlig</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Cordados" title="Cordados – Galician" lang="gl" hreflang="gl" data-title="Cordados" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-inh mw-list-item"><a href="https://inh.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0" title="Хорда – Ingush" lang="inh" hreflang="inh" data-title="Хорда" data-language-autonym="ГӀалгӀай" data-language-local-name="Ingush" class="interlanguage-link-target"><span>ГӀалгӀай</span></a></li><li class="interlanguage-link interwiki-hak mw-list-item"><a href="https://hak.wikipedia.org/wiki/Chit-sok_thung-vu%CC%8Dt" title="Chit-sok thung-vu̍t – Hakka Chinese" lang="hak" hreflang="hak" data-title="Chit-sok thung-vu̍t" data-language-autonym="客家語 / Hak-kâ-ngî" data-language-local-name="Hakka Chinese" class="interlanguage-link-target"><span>客家語 / Hak-kâ-ngî</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%B2%99%EC%82%AD%EB%8F%99%EB%AC%BC" title="척삭동물 – Korean" lang="ko" hreflang="ko" data-title="척삭동물" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D5%94%D5%B8%D6%80%D5%A4%D5%A1%D5%BE%D5%B8%D6%80%D5%B6%D5%A5%D6%80" title="Քորդավորներ – Armenian" lang="hy" hreflang="hy" data-title="Քորդավորներ" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%B0%E0%A4%9C%E0%A5%8D%E0%A4%9C%E0%A5%81%E0%A4%95%E0%A5%80" title="रज्जुकी – Hindi" lang="hi" hreflang="hi" data-title="रज्जुकी" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Svitkovci" title="Svitkovci – Croatian" lang="hr" hreflang="hr" data-title="Svitkovci" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-ilo mw-list-item"><a href="https://ilo.wikipedia.org/wiki/Chordata" title="Chordata – Iloko" lang="ilo" hreflang="ilo" data-title="Chordata" data-language-autonym="Ilokano" data-language-local-name="Iloko" class="interlanguage-link-target"><span>Ilokano</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Chordata" title="Chordata – Indonesian" lang="id" hreflang="id" data-title="Chordata" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ia mw-list-item"><a href="https://ia.wikipedia.org/wiki/Chordato" title="Chordato – Interlingua" lang="ia" hreflang="ia" data-title="Chordato" data-language-autonym="Interlingua" data-language-local-name="Interlingua" class="interlanguage-link-target"><span>Interlingua</span></a></li><li class="interlanguage-link interwiki-os mw-list-item"><a href="https://os.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%C3%A6%D0%B4%D0%B6%D1%8B%D0%BD%D1%82%C3%A6" title="Хордæджынтæ – Ossetic" lang="os" hreflang="os" data-title="Хордæджынтæ" data-language-autonym="Ирон" data-language-local-name="Ossetic" class="interlanguage-link-target"><span>Ирон</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Seild%C3%BDr" title="Seildýr – Icelandic" lang="is" hreflang="is" data-title="Seildýr" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Chordata" title="Chordata – Italian" lang="it" hreflang="it" data-title="Chordata" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9E%D7%99%D7%AA%D7%A8%D7%A0%D7%99%D7%99%D7%9D" title="מיתרניים – Hebrew" lang="he" hreflang="he" data-title="מיתרניים" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-jv mw-list-item"><a href="https://jv.wikipedia.org/wiki/Chordata" title="Chordata – Javanese" lang="jv" hreflang="jv" data-title="Chordata" data-language-autonym="Jawa" data-language-local-name="Javanese" class="interlanguage-link-target"><span>Jawa</span></a></li><li class="interlanguage-link interwiki-kn mw-list-item"><a href="https://kn.wikipedia.org/wiki/%E0%B2%95%E0%B2%BE%E0%B2%B0%E0%B3%8D%E0%B2%A1%E0%B3%87%E0%B2%9F%E0%B3%8D" title="ಕಾರ್ಡೇಟ್ – Kannada" lang="kn" hreflang="kn" data-title="ಕಾರ್ಡೇಟ್" data-language-autonym="ಕನ್ನಡ" data-language-local-name="Kannada" class="interlanguage-link-target"><span>ಕನ್ನಡ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%A5%E1%83%9D%E1%83%A0%E1%83%93%E1%83%98%E1%83%90%E1%83%9C%E1%83%94%E1%83%91%E1%83%98" title="ქორდიანები – Georgian" lang="ka" hreflang="ka" data-title="ქორდიანები" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%BB%D1%8B%D0%BB%D0%B0%D1%80" title="Хордалылар – Kazakh" lang="kk" hreflang="kk" data-title="Хордалылар" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-kw mw-list-item"><a href="https://kw.wikipedia.org/wiki/Chordata" title="Chordata – Cornish" lang="kw" hreflang="kw" data-title="Chordata" data-language-autonym="Kernowek" data-language-local-name="Cornish" class="interlanguage-link-target"><span>Kernowek</span></a></li><li class="interlanguage-link interwiki-sw mw-list-item"><a href="https://sw.wikipedia.org/wiki/Kodata" title="Kodata – Swahili" lang="sw" hreflang="sw" data-title="Kodata" data-language-autonym="Kiswahili" data-language-local-name="Swahili" class="interlanguage-link-target"><span>Kiswahili</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/K%C3%B2de" title="Kòde – Haitian Creole" lang="ht" hreflang="ht" data-title="Kòde" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/St%C3%BBnpi%C5%9Ftdar_(fil%C3%BBm)" title="Stûnpiştdar (filûm) – Kurdish" lang="ku" hreflang="ku" data-title="Stûnpiştdar (filûm)" data-language-autonym="Kurdî" data-language-local-name="Kurdish" class="interlanguage-link-target"><span>Kurdî</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%BB%D1%83%D1%83" title="Хордалуу – Kyrgyz" lang="ky" hreflang="ky" data-title="Хордалуу" data-language-autonym="Кыргызча" data-language-local-name="Kyrgyz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Chordata" title="Chordata – Latin" lang="la" hreflang="la" data-title="Chordata" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Hordai%C5%86i" title="Hordaiņi – Latvian" lang="lv" hreflang="lv" data-title="Hordaiņi" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Chordad%C3%A9ieren" title="Chordadéieren – Luxembourgish" lang="lb" hreflang="lb" data-title="Chordadéieren" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Chordiniai" title="Chordiniai – Lithuanian" lang="lt" hreflang="lt" data-title="Chordiniai" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lij mw-list-item"><a href="https://lij.wikipedia.org/wiki/Chordata" title="Chordata – Ligurian" lang="lij" hreflang="lij" data-title="Chordata" data-language-autonym="Ligure" data-language-local-name="Ligurian" class="interlanguage-link-target"><span>Ligure</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/Chordabieste" title="Chordabieste – Limburgish" lang="li" hreflang="li" data-title="Chordabieste" data-language-autonym="Limburgs" data-language-local-name="Limburgish" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-lfn mw-list-item"><a href="https://lfn.wikipedia.org/wiki/Cordato" title="Cordato – Lingua Franca Nova" lang="lfn" hreflang="lfn" data-title="Cordato" data-language-autonym="Lingua Franca Nova" data-language-local-name="Lingua Franca Nova" class="interlanguage-link-target"><span>Lingua Franca Nova</span></a></li><li class="interlanguage-link interwiki-jbo mw-list-item"><a href="https://jbo.wikipedia.org/wiki/skoselti%27e" title="skoselti'e – Lojban" lang="jbo" hreflang="jbo" data-title="skoselti'e" data-language-autonym="La .lojban." data-language-local-name="Lojban" class="interlanguage-link-target"><span>La .lojban.</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Gerinch%C3%BArosok" title="Gerinchúrosok – Hungarian" lang="hu" hreflang="hu" data-title="Gerinchúrosok" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%BE%D0%B2%D0%B8" title="Хордови – Macedonian" lang="mk" hreflang="mk" data-title="Хордови" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%95%E0%B5%8B%E0%B5%BC%E0%B4%A1%E0%B5%87%E0%B4%B1%E0%B5%8D%E0%B4%B1" title="കോർഡേറ്റ – Malayalam" lang="ml" hreflang="ml" data-title="കോർഡേറ്റ" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-mt mw-list-item"><a href="https://mt.wikipedia.org/wiki/Chordata" title="Chordata – Maltese" lang="mt" hreflang="mt" data-title="Chordata" data-language-autonym="Malti" data-language-local-name="Maltese" class="interlanguage-link-target"><span>Malti</span></a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%95%E0%A4%A3%E0%A4%BE%E0%A4%A7%E0%A4%BE%E0%A4%B0%E0%A5%80_%E0%A4%AA%E0%A5%8D%E0%A4%B0%E0%A4%BE%E0%A4%A3%E0%A5%80" title="कणाधारी प्राणी – Marathi" lang="mr" hreflang="mr" data-title="कणाधारी प्राणी" data-language-autonym="मराठी" data-language-local-name="Marathi" class="interlanguage-link-target"><span>मराठी</span></a></li><li class="interlanguage-link interwiki-xmf mw-list-item"><a href="https://xmf.wikipedia.org/wiki/%E1%83%A5%E1%83%9D%E1%83%A0%E1%83%93%E1%83%98%E1%83%90%E1%83%9C%E1%83%94%E1%83%A4%E1%83%98" title="ქორდიანეფი – Mingrelian" lang="xmf" hreflang="xmf" data-title="ქორდიანეფი" data-language-autonym="მარგალური" data-language-local-name="Mingrelian" class="interlanguage-link-target"><span>მარგალური</span></a></li><li class="interlanguage-link interwiki-arz mw-list-item"><a href="https://arz.wikipedia.org/wiki/%D8%AD%D8%A8%D9%84%D9%8A%D8%A7%D8%AA" title="حبليات – Egyptian Arabic" lang="arz" hreflang="arz" data-title="حبليات" data-language-autonym="مصرى" data-language-local-name="Egyptian Arabic" class="interlanguage-link-target"><span>مصرى</span></a></li><li class="interlanguage-link interwiki-mzn mw-list-item"><a href="https://mzn.wikipedia.org/wiki/%D8%B1%D8%B3%D9%86%E2%80%8C%D8%AF%D8%A7%D8%B1%D9%88%D9%86" title="رسن‌دارون – Mazanderani" lang="mzn" hreflang="mzn" data-title="رسن‌دارون" data-language-autonym="مازِرونی" data-language-local-name="Mazanderani" class="interlanguage-link-target"><span>مازِرونی</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Kordat" title="Kordat – Malay" lang="ms" hreflang="ms" data-title="Kordat" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-mni mw-list-item"><a href="https://mni.wikipedia.org/wiki/%EA%AF%80%EA%AF%A3%EA%AF%94%EA%AF%97%EA%AF%A5%EA%AF%87%EA%AF%A5" title="ꯀꯣꯔꯗꯥꯇꯥ – Manipuri" lang="mni" hreflang="mni" data-title="ꯀꯣꯔꯗꯥꯇꯥ" data-language-autonym="ꯃꯤꯇꯩ ꯂꯣꯟ" data-language-local-name="Manipuri" class="interlanguage-link-target"><span>ꯃꯤꯇꯩ ꯂꯣꯟ</span></a></li><li class="interlanguage-link interwiki-cdo mw-list-item"><a href="https://cdo.wikipedia.org/wiki/C%C3%A9k-s%C3%B3%CC%A4h_d%C3%B4ng-%C5%ADk" title="Cék-só̤h dông-ŭk – Mindong" lang="cdo" hreflang="cdo" data-title="Cék-só̤h dông-ŭk" data-language-autonym="閩東語 / Mìng-dĕ̤ng-ngṳ̄" data-language-local-name="Mindong" class="interlanguage-link-target"><span>閩東語 / Mìng-dĕ̤ng-ngṳ̄</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%A5%D3%A9%D0%B2%D1%87%D1%82%D3%A9%D0%BD" title="Хөвчтөн – Mongolian" lang="mn" hreflang="mn" data-title="Хөвчтөн" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-my mw-list-item"><a href="https://my.wikipedia.org/wiki/%E1%80%80%E1%80%B1%E1%80%AC%E1%80%BA%E1%80%92%E1%80%AD%E1%80%90%E1%80%BA" title="ကော်ဒိတ် – Burmese" lang="my" hreflang="my" data-title="ကော်ဒိတ်" data-language-autonym="မြန်မာဘာသာ" data-language-local-name="Burmese" class="interlanguage-link-target"><span>မြန်မာဘာသာ</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Chordadieren" title="Chordadieren – Dutch" lang="nl" hreflang="nl" data-title="Chordadieren" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E8%84%8A%E7%B4%A2%E5%8B%95%E7%89%A9" title="脊索動物 – Japanese" lang="ja" hreflang="ja" data-title="脊索動物" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-frr mw-list-item"><a href="https://frr.wikipedia.org/wiki/Ragstringdiarten" title="Ragstringdiarten – Northern Frisian" lang="frr" hreflang="frr" data-title="Ragstringdiarten" data-language-autonym="Nordfriisk" data-language-local-name="Northern Frisian" class="interlanguage-link-target"><span>Nordfriisk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Ryggstrengdyr" title="Ryggstrengdyr – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Ryggstrengdyr" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Ryggstrengdyr" title="Ryggstrengdyr – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Ryggstrengdyr" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-nov mw-list-item"><a href="https://nov.wikipedia.org/wiki/Chordata" title="Chordata – Novial" lang="nov" hreflang="nov" data-title="Chordata" data-language-autonym="Novial" data-language-local-name="Novial" class="interlanguage-link-target"><span>Novial</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Chordata" title="Chordata – Occitan" lang="oc" hreflang="oc" data-title="Chordata" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-om mw-list-item"><a href="https://om.wikipedia.org/wiki/Tushaaleeyyii" title="Tushaaleeyyii – Oromo" lang="om" hreflang="om" data-title="Tushaaleeyyii" data-language-autonym="Oromoo" data-language-local-name="Oromo" class="interlanguage-link-target"><span>Oromoo</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Xordalilar" title="Xordalilar – Uzbek" lang="uz" hreflang="uz" data-title="Xordalilar" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%A4%E0%A9%B0%E0%A8%A6%E0%A8%A7%E0%A8%BE%E0%A8%B0%E0%A9%80" title="ਤੰਦਧਾਰੀ – Punjabi" lang="pa" hreflang="pa" data-title="ਤੰਦਧਾਰੀ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%DA%A9%D9%88%D8%B1%DA%88%DB%8C%D9%B9" title="کورڈیٹ – Western Punjabi" lang="pnb" hreflang="pnb" data-title="کورڈیٹ" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-koi mw-list-item"><a href="https://koi.wikipedia.org/wiki/%D0%9C%D1%8B%D1%88%D0%BA%D1%81%C3%B6%D0%BD%D0%B0%D1%8D%D0%B7" title="Мышксöнаэз – Komi-Permyak" lang="koi" hreflang="koi" data-title="Мышксöнаэз" data-language-autonym="Перем коми" data-language-local-name="Komi-Permyak" class="interlanguage-link-target"><span>Перем коми</span></a></li><li class="interlanguage-link interwiki-pcd mw-list-item"><a href="https://pcd.wikipedia.org/wiki/Chordata" title="Chordata – Picard" lang="pcd" hreflang="pcd" data-title="Chordata" data-language-autonym="Picard" data-language-local-name="Picard" class="interlanguage-link-target"><span>Picard</span></a></li><li class="interlanguage-link interwiki-pms mw-list-item"><a href="https://pms.wikipedia.org/wiki/Chordata" title="Chordata – Piedmontese" lang="pms" hreflang="pms" data-title="Chordata" data-language-autonym="Piemontèis" data-language-local-name="Piedmontese" class="interlanguage-link-target"><span>Piemontèis</span></a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Ruggensnarendeerter" title="Ruggensnarendeerter – Low German" lang="nds" hreflang="nds" data-title="Ruggensnarendeerter" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Strunowce" title="Strunowce – Polish" lang="pl" hreflang="pl" data-title="Strunowce" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Cordados" title="Cordados – Portuguese" lang="pt" hreflang="pt" data-title="Cordados" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Cordate" title="Cordate – Romanian" lang="ro" hreflang="ro" data-title="Cordate" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-qu mw-list-item"><a href="https://qu.wikipedia.org/wiki/Wasa_tiwlliyuq" title="Wasa tiwlliyuq – Quechua" lang="qu" hreflang="qu" data-title="Wasa tiwlliyuq" data-language-autonym="Runa Simi" data-language-local-name="Quechua" class="interlanguage-link-target"><span>Runa Simi</span></a></li><li class="interlanguage-link interwiki-rue mw-list-item"><a href="https://rue.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%BE%D0%B2%D1%8B" title="Хордовы – Rusyn" lang="rue" hreflang="rue" data-title="Хордовы" data-language-autonym="Русиньскый" data-language-local-name="Rusyn" class="interlanguage-link-target"><span>Русиньскый</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%BE%D0%B2%D1%8B%D0%B5" title="Хордовые – Russian" lang="ru" hreflang="ru" data-title="Хордовые" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sah mw-list-item"><a href="https://sah.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%BB%D1%8B%D0%BA%D1%82%D0%B0%D1%80" title="Хордалыктар – Yakut" lang="sah" hreflang="sah" data-title="Хордалыктар" data-language-autonym="Саха тыла" data-language-local-name="Yakut" class="interlanguage-link-target"><span>Саха тыла</span></a></li><li class="interlanguage-link interwiki-sco mw-list-item"><a href="https://sco.wikipedia.org/wiki/Chordate" title="Chordate – Scots" lang="sco" hreflang="sco" data-title="Chordate" data-language-autonym="Scots" data-language-local-name="Scots" class="interlanguage-link-target"><span>Scots</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Kordat%C3%ABt" title="Kordatët – Albanian" lang="sq" hreflang="sq" data-title="Kordatët" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-scn mw-list-item"><a href="https://scn.wikipedia.org/wiki/Chordata" title="Chordata – Sicilian" lang="scn" hreflang="scn" data-title="Chordata" data-language-autonym="Sicilianu" data-language-local-name="Sicilian" class="interlanguage-link-target"><span>Sicilianu</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B7%83%E0%B6%BB%E0%B6%A2%E0%B7%8A%E0%B6%A2%E0%B7%94%E0%B6%9A" title="සරජ්ජුක – Sinhala" lang="si" hreflang="si" data-title="සරජ්ජුක" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Chordate" title="Chordate – Simple English" lang="en-simple" hreflang="en-simple" data-title="Chordate" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sd mw-list-item"><a href="https://sd.wikipedia.org/wiki/%DA%AA%D9%88%D8%B1%DA%8A%D9%8A%D9%BD%D8%A7" title="ڪورڊيٽا – Sindhi" lang="sd" hreflang="sd" data-title="ڪورڊيٽا" data-language-autonym="سنڌي" data-language-local-name="Sindhi" class="interlanguage-link-target"><span>سنڌي</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Chord%C3%A1ty" title="Chordáty – Slovak" lang="sk" hreflang="sk" data-title="Chordáty" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Strunarji" title="Strunarji – Slovenian" lang="sl" hreflang="sl" data-title="Strunarji" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D9%85%D8%A7%D8%B2%DB%95%D8%AF%D8%A7%D8%B1%D8%A7%D9%86" title="مازەداران – Central Kurdish" lang="ckb" hreflang="ckb" data-title="مازەداران" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D1%82%D0%B8" title="Хордати – Serbian" lang="sr" hreflang="sr" data-title="Хордати" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Svitkovci" title="Svitkovci – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Svitkovci" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/Chordata" title="Chordata – Sundanese" lang="su" hreflang="su" data-title="Chordata" data-language-autonym="Sunda" data-language-local-name="Sundanese" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Selk%C3%A4j%C3%A4nteiset" title="Selkäjänteiset – Finnish" lang="fi" hreflang="fi" data-title="Selkäjänteiset" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Ryggstr%C3%A4ngsdjur" title="Ryggsträngsdjur – Swedish" lang="sv" hreflang="sv" data-title="Ryggsträngsdjur" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Chordata" title="Chordata – Tagalog" lang="tl" hreflang="tl" data-title="Chordata" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%AE%E0%AF%81%E0%AE%A4%E0%AF%81%E0%AE%95%E0%AF%81%E0%AE%A8%E0%AE%BE%E0%AE%A3%E0%AE%BF" title="முதுகுநாணி – Tamil" lang="ta" hreflang="ta" data-title="முதுகுநாணி" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-kab mw-list-item"><a href="https://kab.wikipedia.org/wiki/Timzikrin" title="Timzikrin – Kabyle" lang="kab" hreflang="kab" data-title="Timzikrin" data-language-autonym="Taqbaylit" data-language-local-name="Kabyle" class="interlanguage-link-target"><span>Taqbaylit</span></a></li><li class="interlanguage-link interwiki-tt mw-list-item"><a href="https://tt.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%B0%D0%BB%D1%8B%D0%BB%D0%B0%D1%80" title="Хордалылар – Tatar" lang="tt" hreflang="tt" data-title="Хордалылар" data-language-autonym="Татарча / tatarça" data-language-local-name="Tatar" class="interlanguage-link-target"><span>Татарча / tatarça</span></a></li><li class="interlanguage-link interwiki-te mw-list-item"><a href="https://te.wikipedia.org/wiki/%E0%B0%95%E0%B0%BE%E0%B0%B0%E0%B1%8D%E0%B0%A1%E0%B1%87%E0%B0%9F%E0%B0%BE" title="కార్డేటా – Telugu" lang="te" hreflang="te" data-title="కార్డేటా" data-language-autonym="తెలుగు" data-language-local-name="Telugu" class="interlanguage-link-target"><span>తెలుగు</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%AA%E0%B8%B1%E0%B8%95%E0%B8%A7%E0%B9%8C%E0%B8%A1%E0%B8%B5%E0%B9%81%E0%B8%81%E0%B8%99%E0%B8%AA%E0%B8%B1%E0%B8%99%E0%B8%AB%E0%B8%A5%E0%B8%B1%E0%B8%87" title="สัตว์มีแกนสันหลัง – Thai" lang="th" hreflang="th" data-title="สัตว์มีแกนสันหลัง" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tg mw-list-item"><a href="https://tg.wikipedia.org/wiki/%D0%A2%D0%B0%D0%BD%D0%BE%D0%B1%D0%B4%D0%BE%D1%80%D0%BE%D0%BD" title="Танобдорон – Tajik" lang="tg" hreflang="tg" data-title="Танобдорон" data-language-autonym="Тоҷикӣ" data-language-local-name="Tajik" class="interlanguage-link-target"><span>Тоҷикӣ</span></a></li><li class="interlanguage-link interwiki-to mw-list-item"><a href="https://to.wikipedia.org/wiki/Monumanu_filo_siliva" title="Monumanu filo siliva – Tongan" lang="to" hreflang="to" data-title="Monumanu filo siliva" data-language-autonym="Lea faka-Tonga" data-language-local-name="Tongan" class="interlanguage-link-target"><span>Lea faka-Tonga</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Kordal%C4%B1lar" title="Kordalılar – Turkish" lang="tr" hreflang="tr" data-title="Kordalılar" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A5%D0%BE%D1%80%D0%B4%D0%BE%D0%B2%D1%96" title="Хордові – Ukrainian" lang="uk" hreflang="uk" data-title="Хордові" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%AD%D8%A8%D9%84%DB%8C%D8%A7%D8%AA" title="حبلیات – Urdu" lang="ur" hreflang="ur" data-title="حبلیات" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-za mw-list-item"><a href="https://za.wikipedia.org/wiki/Doenghduz_ndoencag" title="Doenghduz ndoencag – Zhuang" lang="za" hreflang="za" data-title="Doenghduz ndoencag" data-language-autonym="Vahcuengh" data-language-local-name="Zhuang" class="interlanguage-link-target"><span>Vahcuengh</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/%C4%90%E1%BB%99ng_v%E1%BA%ADt_c%C3%B3_d%C3%A2y_s%E1%BB%91ng" title="Động vật có dây sống – Vietnamese" lang="vi" hreflang="vi" data-title="Động vật có dây sống" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-vls mw-list-item"><a href="https://vls.wikipedia.org/wiki/Chordab%C3%AAestn" title="Chordabêestn – West Flemish" lang="vls" hreflang="vls" data-title="Chordabêestn" data-language-autonym="West-Vlams" data-language-local-name="West Flemish" class="interlanguage-link-target"><span>West-Vlams</span></a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Chordata" title="Chordata – Waray" lang="war" hreflang="war" data-title="Chordata" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E8%84%8A%E7%B4%A2%E5%8A%A8%E7%89%A9" title="脊索动物 – Wu" lang="wuu" hreflang="wuu" data-title="脊索动物" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-yi mw-list-item"><a href="https://yi.wikipedia.org/wiki/%D7%9B%D7%90%D7%A8%D7%93%D7%90%D7%98%D7%9F" title="כארדאטן – Yiddish" lang="yi" hreflang="yi" data-title="כארדאטן" data-language-autonym="ייִדיש" data-language-local-name="Yiddish" class="interlanguage-link-target"><span>ייִדיש</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E8%84%8A%E7%B4%A2%E5%8B%95%E7%89%A9" title="脊索動物 – Cantonese" lang="yue" hreflang="yue" data-title="脊索動物" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-zea mw-list-item"><a href="https://zea.wikipedia.org/wiki/Chordabe%C3%AAsten" title="Chordabeêsten – Zeelandic" lang="zea" hreflang="zea" data-title="Chordabeêsten" data-language-autonym="Zeêuws" data-language-local-name="Zeelandic" class="interlanguage-link-target"><span>Zeêuws</span></a></li><li class="interlanguage-link interwiki-bat-smg mw-list-item"><a href="https://bat-smg.wikipedia.org/wiki/Chuord%C4%97n%C4%93" title="Chuordėnē – Samogitian" lang="sgs" hreflang="sgs" data-title="Chuordėnē" data-language-autonym="Žemaitėška" data-language-local-name="Samogitian" class="interlanguage-link-target"><span>Žemaitėška</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E8%84%8A%E7%B4%A2%E5%8A%A8%E7%89%A9" title="脊索动物 – Chinese" lang="zh" hreflang="zh" data-title="脊索动物" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q10915#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> 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data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="/wiki/Caudata" title="Caudata">Caudata</a>, a group of amphibians.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="/wiki/Cordate_(disambiguation)" class="mw-redirect mw-disambig" title="Cordate (disambiguation)">Cordate (disambiguation)</a>, <a href="/wiki/Cordata_(disambiguation)" class="mw-redirect mw-disambig" title="Cordata (disambiguation)">Cordata (disambiguation)</a>, or <a href="/wiki/Caudate_(disambiguation)" class="mw-redirect mw-disambig" title="Caudate (disambiguation)">Caudate (disambiguation)</a>.</div> <p class="mw-empty-elt"> </p> <table class="infobox biota" style="text-align: left; width: 200px; font-size: 100%"> <tbody><tr> <th colspan="2" style="color:inherit; text-align: center; background-color: rgb(235,235,210)">Chordates<br /><div style="font-size: 85%;">Temporal range: <a href="/wiki/Cambrian_Stage_3" title="Cambrian Stage 3">Cambrian Stage 3</a>–<a href="/wiki/Holocene" title="Holocene">Present</a>, <span class="noprint"><span style="display:inline-block;"></span><span style="display:inline-block;">525–0 <a href="/wiki/Megaannum" class="mw-redirect" title="Megaannum">Ma</a></span><sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> <span style="display:inline-block;"></span><div id="Timeline-row" style="margin: 4px auto 0; clear:both; width:220px; padding:0px; height:18px; overflow:visible; white-space:nowrap; border:1px #666; border-style:solid none; position:relative; z-index:0; font-size:97%;"> <div style="position:absolute; height:100%; left:0px; width:207.23076923077px; padding-left:5px; text-align:left; background-color:rgb(254,217,106); background-image: linear-gradient(to right, rgba(255,255,255,1), rgba(254,217,106,1) 15%, rgba(254,217,106,1));"><a href="/wiki/Precambrian" title="Precambrian">PreꞒ</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(127,160,86); left:37.636923076923px; width:17.583076923077px;"><a href="/wiki/Cambrian" title="Cambrian">Ꞓ</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(0,146,112); left:55.22px; width:14.807692307692px;"><a href="/wiki/Ordovician" title="Ordovician">O</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(179,225,182); left:70.027692307692px; width:7.9470769230769px;"><a href="/wiki/Silurian" title="Silurian">S</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(203,140,55); left:77.974769230769px; width:20.564923076923px;"><a href="/wiki/Devonian" title="Devonian">D</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(103,165,153); left:98.539692307692px; width:20.294153846154px;"><a href="/wiki/Carboniferous" title="Carboniferous">C</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(240,64,40); left:118.83384615385px; width:15.907015384615px;"><a href="/wiki/Permian" title="Permian">P</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(129,43,146); left:134.74086153846px; width:17.092984615385px;"><a href="/wiki/Triassic" title="Triassic">T</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(52,178,201); left:151.83384615385px; width:19.732307692308px;"><a href="/wiki/Jurassic" title="Jurassic">J</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(127,198,78); left:171.56615384615px; width:26.095384615385px;"><a href="/wiki/Cretaceous" title="Cretaceous">K</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(253,154,82); left:197.66153846154px; width:14.540307692308px;"><a href="/wiki/Paleogene" title="Paleogene">Pg</a></div> <div style="position:absolute; height:100%; text-align:center; background-color:rgb(255,230,25); left:212.20184615385px; width:6.9249230769231px;"><a href="/wiki/Neogene" title="Neogene">N</a></div> <div id="end-border" style="position:absolute; height:100%; background-color:#666; width:1px; left:219px"></div><div style="margin:0 auto; line-height:0; clear:both; width:220px; padding:0px; height:8px; overflow:visible; background-color:transparent; position:relative; top:-4px; z-index:100;"><div style="position:absolute; height:8px; left:32.153846153846px; width:187.84615384615px; background-color:#360; opacity:0.42;"></div> <div style="position:absolute; height:8px; left:42.307692307692px; width:177.69230769231px; background-color:#360; opacity:1;"></div> <div style="position:absolute; height:6px; top:1px; left:43.307692307692px; width:175.69230769231px; background-color:#6c3;"></div> </div> </div></span> (Possible <a href="/wiki/Ediacaran" title="Ediacaran">Ediacaran</a> record, 555 Ma<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>)</div> </th></tr> <tr> <td colspan="2" style="text-align: center"><figure class="noresize mw-ext-imagemap-desc-bottom-right" typeof="mw:File"><span><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5a/Chordata.png/250px-Chordata.png" decoding="async" width="220" height="169" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5a/Chordata.png/330px-Chordata.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5a/Chordata.png/500px-Chordata.png 2x" data-file-width="1300" data-file-height="1000" usemap="#ImageMap_1afb53565e3b21a4" resource="/wiki/File:Chordata.png" /></span><map name="ImageMap_1afb53565e3b21a4"><area href="/wiki/Lancelet" shape="rect" coords="0,0,110,85" alt="Lancelet" title="Lancelet" /><area href="/wiki/Chondrichthyes" shape="rect" coords="0,85,110,169" alt="Chondrichthyes" title="Chondrichthyes" /><area href="/wiki/Tunicate" shape="rect" coords="110,0,220,85" alt="Tunicate" title="Tunicate" /><area href="/wiki/Tetrapod" shape="rect" coords="110,85,203,169" alt="Tetrapod" title="Tetrapod" /></map><figcaption></figcaption></figure> </td></tr> <tr> <th colspan="2" style="color:inherit; min-width:15em; text-align: center; background-color: rgb(235,235,210)"><a href="/wiki/Taxonomy_(biology)" title="Taxonomy (biology)">Scientific classification</a> <span class="plainlinks taxobox-edit-taxonomy skin-invert" style="font-size:smaller; float:right; padding-right:0.4em; margin-left:-3em;"><span typeof="mw:File"><a href="/wiki/Template:Taxonomy/Chordata" title="Edit this classification"><img alt="Edit this classification" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/OOjs_UI_icon_edit-ltr.svg/15px-OOjs_UI_icon_edit-ltr.svg.png" decoding="async" width="15" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/OOjs_UI_icon_edit-ltr.svg/23px-OOjs_UI_icon_edit-ltr.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8a/OOjs_UI_icon_edit-ltr.svg/30px-OOjs_UI_icon_edit-ltr.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></span> </th></tr> <tr> <td>Domain: </td> <td><a href="/wiki/Eukaryote" title="Eukaryote">Eukaryota</a> </td></tr> <tr> <td>Kingdom: </td> <td><a href="/wiki/Animal" title="Animal">Animalia</a> </td></tr> <tr> <td>Subkingdom: </td> <td><a href="/wiki/Eumetazoa" title="Eumetazoa">Eumetazoa</a> </td></tr> <tr> <td><i>Clade</i>: </td> <td><a href="/wiki/ParaHoxozoa" title="ParaHoxozoa">ParaHoxozoa</a> </td></tr> <tr> <td><i>Clade</i>: </td> <td><a href="/wiki/Bilateria" title="Bilateria">Bilateria</a> </td></tr> <tr> <td><i>Clade</i>: </td> <td><a href="/wiki/Nephrozoa" title="Nephrozoa">Nephrozoa</a> </td></tr> <tr> <td>Superphylum: </td> <td><a href="/wiki/Deuterostome" title="Deuterostome">Deuterostomia</a> </td></tr> <tr> <td>Phylum: </td> <td><a class="mw-selflink selflink">Chordata</a><br /><small><a href="/wiki/Ernst_Haeckel" title="Ernst Haeckel">Haeckel</a>, 1874<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Nielsen2012_4-0" class="reference"><a href="#cite_note-Nielsen2012-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup></small> </td></tr> <tr> <th colspan="2" style="color:inherit; text-align: center; background-color: rgb(235,235,210)">Subgroups </th></tr> <tr> <td colspan="2" style="text-align: left"> <ul><li>†<a href="/wiki/Vetulocystidae" title="Vetulocystidae">Vetulocystidae</a>?<sup id="cite_ref-He2023_5-0" class="reference"><a href="#cite_note-He2023-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li>†<a href="/wiki/Vetulicolia" title="Vetulicolia">Vetulicolia</a>? <span style="font-size: 85%;">(<a href="/wiki/Paraphyletic" class="mw-redirect" title="Paraphyletic">Paraphyletic</a>?)</span><sup id="cite_ref-Mussini2024_6-0" class="reference"><a href="#cite_note-Mussini2024-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup></li> <li>†<i><a href="/wiki/Yunnanozoon" title="Yunnanozoon">Yunnanozoon</a></i>?</li> <li>†<i><a href="/wiki/Cathaymyrus" title="Cathaymyrus">Cathaymyrus</a></i></li> <li>†<i><a href="/wiki/Pikaia" title="Pikaia">Pikaia</a></i></li> <li><a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">Cephalochordata</a></li> <li><a href="/wiki/Olfactores" title="Olfactores">Olfactores</a> <ul><li><a href="/wiki/Tunicate" title="Tunicate">Tunicata</a></li> <li>Total group Vertebrata/Craniata <ul><li>†<i><a href="/wiki/Emmonsaspis" title="Emmonsaspis">Emmonsaspis</a></i><sup id="cite_ref-Lerosey-Aubril2024_7-0" class="reference"><a href="#cite_note-Lerosey-Aubril2024-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></li> <li>†<i><a href="/wiki/Metaspriggina" title="Metaspriggina">Metaspriggina</a></i></li> <li>†<i><a href="/wiki/Nuucichthys" title="Nuucichthys">Nuucichthys</a></i><sup id="cite_ref-Lerosey-Aubril2024_7-1" class="reference"><a href="#cite_note-Lerosey-Aubril2024-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></li> <li>†<a href="/wiki/Myllokunmingiidae" title="Myllokunmingiidae">Myllokunmingiidae</a></li> <li>†<a href="/wiki/Conodont" title="Conodont">Conodonta</a>?<sup id="cite_ref-He2023_5-1" class="reference"><a href="#cite_note-He2023-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Vertebrate" title="Vertebrate">Vertebrata</a></li></ul></li></ul></li></ul> <p>And see <a href="#Classification">text</a> </p> </td></tr> </tbody></table><style data-mw-deduplicate="TemplateStyles:r1238732961">@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox.biota tr{background:transparent!important}html.skin-theme-clientpref-night .mw-parser-output .infobox.biota img{background:transparent}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox.biota tr{background:transparent!important}html.skin-theme-clientpref-os .mw-parser-output .infobox.biota img{background:white}}.mw-parser-output .infobox.biota .taxobox-edit-taxonomy img{background:transparent!important}body.skin-vector .mw-parser-output table.biota.infobox{margin-top:0.5em}body.skin--responsive .mw-parser-output table.biota.infobox tr.taxonrow td{padding:2px 10px}</style> <p>A <b>chordate</b> (<span class="rt-commentedText nowrap"><span class="IPA nopopups noexcerpt" lang="en-fonipa"><a href="/wiki/Help:IPA/English" title="Help:IPA/English">/<span style="border-bottom:1px dotted"><span title="/ˈ/: primary stress follows">ˈ</span><span title="'k' in 'kind'">k</span><span title="/ɔːr/: 'ar' in 'war'">ɔːr</span><span title="'d' in 'dye'">d</span><span title="/eɪ/: 'a' in 'face'">eɪ</span><span title="'t' in 'tie'">t</span></span>/</a></span></span> <a href="/wiki/Help:Pronunciation_respelling_key" title="Help:Pronunciation respelling key"><i title="English pronunciation respelling"><span style="font-size:90%">KOR</span>-dayt</i></a>) is a <a href="/wiki/Bilateria" title="Bilateria">bilaterian</a> <a href="/wiki/Animal" title="Animal">animal</a> belonging to the <a href="/wiki/Phylum" title="Phylum">phylum</a> <b>Chordata</b> (<span class="rt-commentedText nowrap"><span class="IPA nopopups noexcerpt" lang="en-fonipa"><a href="/wiki/Help:IPA/English" title="Help:IPA/English">/<span style="border-bottom:1px dotted"><span title="'k' in 'kind'">k</span><span title="/ɔːr/: 'ar' in 'war'">ɔːr</span><span title="/ˈ/: primary stress follows">ˈ</span><span title="'d' in 'dye'">d</span><span title="/eɪ/: 'a' in 'face'">eɪ</span><span title="'t' in 'tie'">t</span><span title="/ə/: 'a' in 'about'">ə</span></span>/</a></span></span> <a href="/wiki/Help:Pronunciation_respelling_key" title="Help:Pronunciation respelling key"><i title="English pronunciation respelling">kor-<span style="font-size:90%">DAY</span>-tə</i></a>). All chordates possess, at some point during their larval or adult stages, five distinctive physical characteristics (<a href="/wiki/Apomorphy_and_synapomorphy" title="Apomorphy and synapomorphy">synapomorphies</a>) that distinguish them from other <a href="/wiki/Taxon" title="Taxon">taxa</a>. These five synapomorphies are a <a href="/wiki/Notochord" title="Notochord">notochord</a>, a <a href="/wiki/Neural_tube" title="Neural tube">hollow</a> <a href="/wiki/Dorsal_nerve_cord" title="Dorsal nerve cord">dorsal nerve cord</a>, an <a href="/wiki/Endostyle" title="Endostyle">endostyle</a> or <a href="/wiki/Thyroid" title="Thyroid">thyroid</a>, <a href="/wiki/Pharyngeal_slit" title="Pharyngeal slit">pharyngeal slits</a>, and a post-<a href="/wiki/Anus" title="Anus">anal</a> <a href="/wiki/Tail" title="Tail">tail</a>.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>In addition to the morphological characteristics used to define chordates, analysis of genome sequences has identified two <a href="/wiki/Conserved_signature_indels" title="Conserved signature indels">conserved signature indels</a> (CSIs) in their proteins: <a href="/wiki/Cyclophilin" title="Cyclophilin">cyclophilin</a>-like protein and <a href="/wiki/Inner_mitochondrial_membrane" title="Inner mitochondrial membrane">inner mitochondrial membrane</a> <a href="/wiki/Protease" title="Protease">protease</a> ATP23, which are exclusively shared by all <a href="/wiki/Vertebrate" title="Vertebrate">vertebrates</a>, <a href="/wiki/Tunicate" title="Tunicate">tunicates</a> and <a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">cephalochordates</a>.<sup id="cite_ref-:0_9-0" class="reference"><a href="#cite_note-:0-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> These CSIs provide molecular means to reliably distinguish chordates from all other <a href="/wiki/Animal" title="Animal">animals</a>. </p><p>Chordates are divided into three <a href="/wiki/Phylum" title="Phylum">subphyla</a>: <a href="/wiki/Vertebrata" class="mw-redirect" title="Vertebrata">Vertebrata</a> (<a href="/wiki/Fish" title="Fish">fish</a>, <a href="/wiki/Amphibian" title="Amphibian">amphibians</a>, <a href="/wiki/Reptile" title="Reptile">reptiles</a>, <a href="/wiki/Bird" title="Bird">birds</a> and <a href="/wiki/Mammal" title="Mammal">mammals</a>), whose notochords are replaced by a <a href="/wiki/Cartilaginous" class="mw-redirect" title="Cartilaginous">cartilaginous</a>/<a href="/wiki/Bone" title="Bone">bony</a> <a href="/wiki/Axial_skeleton" title="Axial skeleton">axial</a> <a href="/wiki/Endoskeleton" title="Endoskeleton">endoskeleton</a> (<a href="/wiki/Vertebral_column" class="mw-redirect" title="Vertebral column">spine</a>) and are <a href="/wiki/Cladistics" title="Cladistics">cladistically</a> and <a href="/wiki/Phylogenetics" title="Phylogenetics">phylogenetically</a> a subgroup of the <a href="/wiki/Clade" title="Clade">clade</a> <a href="/wiki/Craniata" class="mw-redirect" title="Craniata">Craniata</a> (i.e. chordates with a <a href="/wiki/Skull" title="Skull">skull</a>); <a href="/wiki/Tunicata" class="mw-redirect" title="Tunicata">Tunicata</a> or <a href="/wiki/Urochordata" class="mw-redirect" title="Urochordata">Urochordata</a> (<a href="/wiki/Sea_squirt" class="mw-redirect" title="Sea squirt">sea squirts</a>, <a href="/wiki/Salp" title="Salp">salps</a>, and <a href="/wiki/Larvacean" title="Larvacean">larvaceans</a>), which only retain the synapomorphies during their <a href="/wiki/Larva" title="Larva">larval</a> stage; and <a href="/wiki/Cephalochordata" class="mw-redirect" title="Cephalochordata">Cephalochordata</a> (<a href="/wiki/Lancelet" title="Lancelet">lancelets</a>), which resemble <a href="/wiki/Jawless_fish" class="mw-redirect" title="Jawless fish">jawless fish</a> but have no <a href="/wiki/Gill" title="Gill">gills</a> or a distinct <a href="/wiki/Head" title="Head">head</a>. The vertebrates and tunicates compose the clade <a href="/wiki/Olfactores" title="Olfactores">Olfactores</a>, which is sister to Cephalochordata (see diagram under <a href="#Phylogeny">Phylogeny</a>). Extinct taxa such as the <a href="/wiki/Conodont" title="Conodont">conodonts</a> are chordates, but their internal placement is less certain. <a href="/wiki/Hemichordate" title="Hemichordate">Hemichordata</a> (which includes the <a href="/wiki/Acorn_worm" title="Acorn worm">acorn worms</a>) was previously considered a fourth chordate subphylum, but now is treated as a separate phylum which are now thought to be closer to the <a href="/wiki/Echinoderm" title="Echinoderm">echinoderms</a>, and together they form the clade <a href="/wiki/Ambulacraria" title="Ambulacraria">Ambulacraria</a>, the sister phylum of the chordates. Chordata, Ambulacraria, and possibly <a href="/wiki/Xenacoelomorpha" title="Xenacoelomorpha">Xenacoelomorpha</a> are believed to form the superphylum <a href="/wiki/Deuterostome" title="Deuterostome">Deuterostomia</a>, although this has recently been called into doubt.<sup id="cite_ref-telford_10-0" class="reference"><a href="#cite_note-telford-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>Chordata is the third-largest phylum of the animal <a href="/wiki/Kingdom_(biology)" title="Kingdom (biology)">kingdom</a> (behind only the <a href="/wiki/Protostoma" class="mw-redirect" title="Protostoma">protostomal</a> phyla <a href="/wiki/Arthropoda" class="mw-redirect" title="Arthropoda">Arthropoda</a> and <a href="/wiki/Mollusca" title="Mollusca">Mollusca</a>) and is also one of the most ancient animal taxons. Chordate <a href="/wiki/Fossil" title="Fossil">fossils</a> have been found from as early as the <a href="/wiki/Cambrian_explosion" title="Cambrian explosion">Cambrian explosion</a> over 539 million years ago.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Of the more than 81,000<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> living species of chordates, about half are <a href="/wiki/Ray-finned_fish" class="mw-redirect" title="Ray-finned fish">ray-finned fishes</a> (<a href="/wiki/Class_(biology)" title="Class (biology)">class</a> <a href="/wiki/Actinopterygii" title="Actinopterygii">Actinopterygii</a>) and the vast majority of the rest are <a href="/wiki/Tetrapod" title="Tetrapod">tetrapods</a>, a <a href="/wiki/Terrestrial_animal" title="Terrestrial animal">terrestrial</a> clade of <a href="/wiki/Lobe-finned_fish" class="mw-redirect" title="Lobe-finned fish">lobe-finned fishes</a> (<a href="/wiki/Sarcopterygii" title="Sarcopterygii">Sarcopterygii</a>) who evolved air-breathing using <a href="/wiki/Lung" title="Lung">lungs</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Etymology">Etymology</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=1" title="Edit section: Etymology"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The name "chordate" comes from the first of these synapomorphies, the notochord, which plays a significant role in chordate <a href="/wiki/Body_plan" title="Body plan">body plan</a> structuring and movements. Chordates are also <a href="/wiki/Symmetry_in_biology#Bilateral_symmetry" title="Symmetry in biology">bilaterally symmetric</a>, have a <a href="/wiki/Coelom" title="Coelom">coelom</a>, possess a <a href="/wiki/Circulatory_system#Closed_circulatory_system" title="Circulatory system">closed</a> <a href="/wiki/Circulatory_system" title="Circulatory system">circulatory system</a>, and exhibit <a href="/wiki/Metamerism_(biology)" title="Metamerism (biology)">metameric segmentation</a>. Although the name Chordata is attributed to <a href="/wiki/William_Bateson" title="William Bateson">William Bateson</a> (1885), it was already in prevalent use by 1880. <a href="/wiki/Ernst_Haeckel" title="Ernst Haeckel">Ernst Haeckel</a> described a taxon comprising tunicates, cephalochordates, and vertebrates in 1866. Though he used the German vernacular form, it is allowed under the <a href="/wiki/International_Code_of_Zoological_Nomenclature" title="International Code of Zoological Nomenclature">ICZN code</a> because of its subsequent latinization.<sup id="cite_ref-Nielsen2012_4-1" class="reference"><a href="#cite_note-Nielsen2012-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Anatomy">Anatomy</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=2" title="Edit section: Anatomy"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Kryptopterus_2.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Kryptopterus_2.jpg/250px-Kryptopterus_2.jpg" decoding="async" width="220" height="123" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Kryptopterus_2.jpg/330px-Kryptopterus_2.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Kryptopterus_2.jpg/500px-Kryptopterus_2.jpg 2x" data-file-width="591" data-file-height="331" /></a><figcaption>The glass catfish (<i><a href="/wiki/Kryptopterus_vitreolus" title="Kryptopterus vitreolus">Kryptopterus vitreolus</a></i>) is one of the few chordates with a visible <a href="/wiki/Vertebral_column" class="mw-redirect" title="Vertebral column">backbone</a>. The <a href="/wiki/Spinal_cord" title="Spinal cord">spinal cord</a> is housed within its backbone.</figcaption></figure> <p>Chordates form a <a href="/wiki/Phylum" title="Phylum">phylum</a> of animals that are defined by having at some stage in their lives all of the following anatomical features:<sup id="cite_ref-RychelSmithShimamotoSwalla2006_13-0" class="reference"><a href="#cite_note-RychelSmithShimamotoSwalla2006-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> <ul><li>A <a href="/wiki/Notochord" title="Notochord">notochord</a>, a stiff but elastic rod of <a href="/wiki/Glycoprotein" title="Glycoprotein">glycoprotein</a> wrapped in two <a href="/wiki/Collagen" title="Collagen">collagen</a> helices, which extends along the central axis of the body. Among members of the <a href="/wiki/Subphylum" title="Subphylum">subphylum</a> <a href="/wiki/Vertebrata" class="mw-redirect" title="Vertebrata">Vertebrata</a> (vertebrates), the notochord gets replaced by <a href="/wiki/Hyaline_cartilage" title="Hyaline cartilage">hyaline cartilage</a> or <a href="/wiki/Osseous_tissue" class="mw-redirect" title="Osseous tissue">osseous tissue</a> of the <a href="/wiki/Vertebral_column" class="mw-redirect" title="Vertebral column">spine</a>, and notochord remnants develop into the <a href="/wiki/Intervertebral_disc" title="Intervertebral disc">intervertebral discs</a>, which allow adjacent spinal <a href="/wiki/Vertebra" title="Vertebra">vertebrae</a> to bend and twist relative to each other. In wholly aquatic species, this helps the animal swim efficiently by <a href="/wiki/Fish_locomotion#Body/caudal_fin_propulsion" title="Fish locomotion">flexing its tail side-to-side</a>.</li> <li>A hollow <a href="/wiki/Dorsal_nerve_cord" title="Dorsal nerve cord">dorsal nerve cord</a>, also known as the <a href="/wiki/Neural_tube" title="Neural tube">neural tube</a>, which develops into the <a href="/wiki/Spinal_cord" title="Spinal cord">spinal cord</a>, the main communications trunk of the <a href="/wiki/Nervous_system" title="Nervous system">nervous system</a>. In vertebrates, the <a href="/wiki/Rostral_(anatomical_term)" class="mw-redirect" title="Rostral (anatomical term)">rostral</a> end of the neural tube enlarges into several <a href="/wiki/Brain_vesicle" title="Brain vesicle">vesicles</a> during <a href="/wiki/Embryonic_development" class="mw-redirect" title="Embryonic development">embryonic development</a>, which give rise to the <a href="/wiki/Brain" title="Brain">brain</a>.</li> <li><a href="/wiki/Pharyngeal_slit" title="Pharyngeal slit">Pharyngeal slits</a>. The <a href="/wiki/Pharynx" title="Pharynx">pharynx</a> is the part of the <a href="/wiki/Throat" title="Throat">throat</a> immediately behind the <a href="/wiki/Mouth" title="Mouth">mouth</a>. In <a href="/wiki/Fish" title="Fish">fish</a>, the slits are modified to form <a href="/wiki/Gill" title="Gill">gills</a>, but in some other chordates they are part of a <a href="/wiki/Filter_feeding" class="mw-redirect" title="Filter feeding">filter-feeding</a> system that extracts food particles from ingested water. In <a href="/wiki/Tetrapod" title="Tetrapod">tetrapods</a>, they are only present during embryonic stages of the development.</li> <li>A post-<a href="/wiki/Anus" title="Anus">anal</a> <a href="/wiki/Tail" title="Tail">tail</a>. A muscular tail that extends backwards beyond the location of the anus. In some chordates such as <a href="/wiki/Hominid" class="mw-redirect" title="Hominid">hominids</a>, this is only present in the embryonic stage.</li> <li>An <a href="/wiki/Endostyle" title="Endostyle">endostyle</a>. This is a groove in the <a href="/wiki/Ventral" class="mw-redirect" title="Ventral">ventral</a> wall of the pharynx. In <a href="/wiki/Filter-feeding" class="mw-redirect" title="Filter-feeding">filter-feeding</a> species it produces <a href="/wiki/Mucus" title="Mucus">mucus</a> to gather food particles, which helps in transporting food to the <a href="/wiki/Esophagus" title="Esophagus">esophagus</a>.<sup id="cite_ref-Ruppert2005_14-0" class="reference"><a href="#cite_note-Ruppert2005-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> It also stores <a href="/wiki/Iodine" title="Iodine">iodine</a>, and may be a precursor of the vertebrate <a href="/wiki/Thyroid_gland" class="mw-redirect" title="Thyroid gland">thyroid gland</a>.<sup id="cite_ref-RychelSmithShimamotoSwalla2006_13-1" class="reference"><a href="#cite_note-RychelSmithShimamotoSwalla2006-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup></li></ul> <p>There are soft constraints that separate chordates from other biological lineages, but are not part of the formal definition: </p> <ul><li>All chordates are <a href="/wiki/Deuterostome" title="Deuterostome">deuterostomes</a>. This means that, during <a href="/wiki/Embryonic_development" class="mw-redirect" title="Embryonic development">embryonic development</a>, the anus forms before the mouth does.</li> <li>All chordates are based on a <a href="/wiki/Bilateral_symmetry" class="mw-redirect" title="Bilateral symmetry">bilateral</a> <a href="/wiki/Body_plan" title="Body plan">body plan</a>.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup></li> <li>All chordates are <a href="/wiki/Coelomate" class="mw-redirect" title="Coelomate">coelomates</a>, and have a fluid-filled <a href="/wiki/Body_cavity" title="Body cavity">body cavity</a> (<a href="/wiki/Coelom" title="Coelom">coelom</a>) with a complete <a href="/wiki/Serosa" class="mw-redirect" title="Serosa">serosal</a> lining derived from <a href="/wiki/Mesoderm" title="Mesoderm">mesoderm</a> called <a href="/wiki/Mesothelium" title="Mesothelium">mesothelium</a> (see <a href="/wiki/Taxonomy_of_invertebrates_(Brusca_%26_Brusca,_2003)" title="Taxonomy of invertebrates (Brusca & Brusca, 2003)">Brusca and Brusca</a>).<sup id="cite_ref-Brusca_16-0" class="reference"><a href="#cite_note-Brusca-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup></li></ul> <div class="center"><div class="noresize thumb tnone" style=";"> <div class="thumbinner" style="overflow:hidden;width:402px;"> <div class="thumbimage" style="height:342px; overflow:hidden; position:relative; background-color:white;"> <div style=";left:0px; top:0px; width:400px; position:absolute;"> <span typeof="mw:File"><a href="/wiki/File:BranchiostomaLanceolatum_PioM.svg" class="mw-file-description" title="Anatomy of the cephalochordate Branchiostoma lanceolatum. Bolded items are components of all chordates at some point in their lifetimes, and distinguish them from other phyla."><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/d/da/BranchiostomaLanceolatum_PioM.svg/400px-BranchiostomaLanceolatum_PioM.svg.png" decoding="async" width="400" height="130" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/da/BranchiostomaLanceolatum_PioM.svg/600px-BranchiostomaLanceolatum_PioM.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/da/BranchiostomaLanceolatum_PioM.svg/800px-BranchiostomaLanceolatum_PioM.svg.png 2x" data-file-width="2165" data-file-height="704" /></a></span></div> <div style="text-align:left; background-color:transparent; line-height:110%;"> <div id="annotation_5x145" style="position:absolute; left:5px; top:145px; line-height:110%;"><span style="background-color:transparent; color:inherit;">1 = bulge in <a href="/wiki/Spinal_cord" title="Spinal cord">spinal cord</a> ("brain")</span></div> <b><div id="annotation_5x165" style="position:absolute; left:5px; top:165px; line-height:110%;"><span style="background-color:transparent; color:inherit;">2 = <a href="/wiki/Notochord" title="Notochord">notochord</a> </span></div></b> <b><div id="annotation_5x185" style="position:absolute; left:5px; top:185px; line-height:110%;"><span style="background-color:transparent; color:inherit;">3 = <a href="/wiki/Dorsal_nerve_cord" title="Dorsal nerve cord">dorsal nerve cord</a> </span></div></b> <b><div id="annotation_5x205" style="position:absolute; left:5px; top:205px; line-height:110%;"><span style="background-color:transparent; color:inherit;">4 = post-anal tail </span></div></b> <div id="annotation_5x225" style="position:absolute; left:5px; top:225px; line-height:110%;"><span style="background-color:transparent; color:inherit;">5 = <a href="/wiki/Anus" title="Anus">anus</a> </span></div> <div id="annotation_5x245" style="position:absolute; left:5px; top:245px; line-height:110%;"><span style="background-color:transparent; color:inherit;">6 = <a href="/wiki/Alimentary_canal" class="mw-redirect" title="Alimentary canal">digestive canal</a> </span></div> <div id="annotation_5x265" style="position:absolute; left:5px; top:265px; line-height:110%;"><span style="background-color:transparent; color:inherit;">7 = <a href="/wiki/Circulatory_system" title="Circulatory system">circulatory system</a> </span></div> <div id="annotation_5x285" style="position:absolute; left:5px; top:285px; line-height:110%;"><span style="background-color:transparent; color:inherit;">8 = <a href="/wiki/Atriopore" class="mw-redirect" title="Atriopore">atriopore</a> </span></div> <div id="annotation_5x305" style="position:absolute; left:5px; top:305px; line-height:110%;"><span style="background-color:transparent; color:inherit;">9 = space above <a href="/wiki/Pharynx" title="Pharynx">pharynx</a> </span></div> <b><div id="annotation_5x325" style="position:absolute; left:5px; top:325px; line-height:110%;"><span style="background-color:transparent; color:inherit;">10 = <a href="/wiki/Pharyngeal_slit" title="Pharyngeal slit">pharyngeal slit</a> (<a href="/wiki/Gill" title="Gill">gill</a>)</span></div></b> <div id="annotation_200x145" style="position:absolute; left:200px; top:145px; line-height:110%;"><span style="background-color:transparent; color:inherit;">11 = <a href="/wiki/Pharynx" title="Pharynx">pharynx</a> </span></div> <div id="annotation_200x165" style="position:absolute; left:200px; top:165px; line-height:110%;"><span style="background-color:transparent; color:inherit;">12 = <a href="/wiki/Vestibule_of_mouth" class="mw-redirect" title="Vestibule of mouth">vestibule</a> </span></div> <div id="annotation_200x185" style="position:absolute; left:200px; top:185px; line-height:110%;"><span style="background-color:transparent; color:inherit;">13 = oral <a href="/wiki/Cilium" title="Cilium">cirri</a> </span></div> <div id="annotation_200x205" style="position:absolute; left:200px; top:205px; line-height:110%;"><span style="background-color:transparent; color:inherit;">14 = mouth opening </span></div> <div id="annotation_200x225" style="position:absolute; left:200px; top:225px; line-height:110%;"><span style="background-color:transparent; color:inherit;">15 = <a href="/wiki/Gonad" title="Gonad">gonads</a> (<a href="/wiki/Ovary" title="Ovary">ovary</a> / <a href="/wiki/Testicle" title="Testicle">testicle</a>) </span></div> <div id="annotation_200x245" style="position:absolute; left:200px; top:245px; line-height:110%;"><span style="background-color:transparent; color:inherit;">16 = light sensor </span></div> <div id="annotation_200x265" style="position:absolute; left:200px; top:265px; line-height:110%;"><span style="background-color:transparent; color:inherit;">17 = <a href="/wiki/Nerves" class="mw-redirect" title="Nerves">nerves</a> </span></div> <div id="annotation_200x285" style="position:absolute; left:200px; top:285px; line-height:110%;"><span style="background-color:transparent; color:inherit;">18 = <a href="/w/index.php?title=Metapleural_fold&action=edit&redlink=1" class="new" title="Metapleural fold (page does not exist)">metapleural fold</a> </span></div> <div id="annotation_200x305" style="position:absolute; left:200px; top:305px; line-height:110%;"><span style="background-color:transparent; color:inherit;">19 = <a href="/wiki/Hepatic_caecum" title="Hepatic caecum">hepatic caecum</a> (<a href="/wiki/Liver" title="Liver">liver</a>-like sack) </span></div> </div> <div style="visibility:hidden"><span class="noviewer" typeof="mw:File/Frameless"><a href="/wiki/File:BranchiostomaLanceolatum_PioM.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/d/da/BranchiostomaLanceolatum_PioM.svg/400px-BranchiostomaLanceolatum_PioM.svg.png" decoding="async" width="400" height="130" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/da/BranchiostomaLanceolatum_PioM.svg/600px-BranchiostomaLanceolatum_PioM.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/da/BranchiostomaLanceolatum_PioM.svg/800px-BranchiostomaLanceolatum_PioM.svg.png 2x" data-file-width="2165" data-file-height="704" /></a></span></div> </div> <div class="thumbcaption"><div class="magnify"><a href="/wiki/File:BranchiostomaLanceolatum_PioM.svg" title="File:BranchiostomaLanceolatum PioM.svg"> </a></div>Anatomy of the <a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">cephalochordate</a> <i><a href="/wiki/Branchiostoma_lanceolatum" title="Branchiostoma lanceolatum">Branchiostoma lanceolatum</a></i>. Bolded items are components of all chordates at some point in their lifetimes, and distinguish them from other phyla.</div> </div></div></div> <div class="mw-heading mw-heading2"><h2 id="Classification">Classification</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=3" title="Edit section: Classification"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The following schema is from the 2015 edition of <i><a href="/wiki/Vertebrate_Palaeontology_(Benton)" class="mw-redirect" title="Vertebrate Palaeontology (Benton)">Vertebrate Palaeontology</a></i>.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> The invertebrate chordate classes are from <i><a href="/wiki/Fishes_of_the_World" title="Fishes of the World">Fishes of the World</a></i>.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> While it is structured so as to reflect evolutionary relationships (similar to a <a href="/wiki/Cladistics" title="Cladistics">cladogram</a>), it also retains the traditional ranks used in <a href="/wiki/Linnaean_taxonomy" title="Linnaean taxonomy">Linnaean taxonomy</a>. </p> <ul><li><b>Phylum Chordata</b> <ul><li>Subphylum <b><a href="/wiki/Cephalochordata" class="mw-redirect" title="Cephalochordata">Cephalochordata</a></b> (Acraniata) – (lancelets; 30 species) <ul><li>Class <b><a href="/wiki/Leptocardii" class="mw-redirect" title="Leptocardii">Leptocardii</a></b> (lancelets)</li></ul></li> <li>Subphylum <b><a href="/wiki/Urochordata" class="mw-redirect" title="Urochordata">Tunicata</a></b> (Urochordata) – (tunicates; 3,000 species) <ul><li>Class <b><a href="/wiki/Ascidiacea" title="Ascidiacea">Ascidiacea</a></b> (sea squirts)</li> <li>Class <b><a href="/wiki/Thaliacea" title="Thaliacea">Thaliacea</a></b> (salps, doliolids and pyrosomes)</li> <li>Class <b><a href="/wiki/Larvacean" title="Larvacean">Appendicularia</a></b> (larvaceans)</li></ul></li> <li>Subphylum <b><a href="/wiki/Vertebrata" class="mw-redirect" title="Vertebrata">Vertebrata</a></b> (<a href="/wiki/Craniata" class="mw-redirect" title="Craniata">Craniata</a>) (vertebrates – animals with backbones; 66,100+ species) <ul><li>Superclass '<b><a href="/wiki/Agnatha" title="Agnatha">Agnatha</a>'</b> <a href="/wiki/Paraphyletic" class="mw-redirect" title="Paraphyletic">paraphyletic</a> (jawless vertebrates; 100+ species) <ul><li>Class <b><a href="/wiki/Cyclostomata" class="mw-redirect" title="Cyclostomata">Cyclostomata</a></b> <ul><li>Infraclass <a href="/wiki/Myxinoidea" class="mw-redirect" title="Myxinoidea">Myxinoidea</a> or <a href="/wiki/Myxini" class="mw-redirect" title="Myxini">Myxini</a> (hagfish; 65 species)</li> <li>Infraclass <a href="/wiki/Petromyzontida" class="mw-redirect" title="Petromyzontida">Petromyzontida</a> or <a href="/wiki/Hyperoartia" class="mw-redirect" title="Hyperoartia">Hyperoartia</a> (lampreys)</li></ul></li> <li>Class †<a href="/wiki/Conodonta" class="mw-redirect" title="Conodonta">Conodonta</a></li> <li>Class †<a href="/wiki/Myllokunmingiida" class="mw-redirect" title="Myllokunmingiida">Myllokunmingiida</a></li> <li>Class †<a href="/wiki/Pteraspidomorphi" title="Pteraspidomorphi">Pteraspidomorphi</a></li> <li>Class †<a href="/wiki/Thelodonti" title="Thelodonti">Thelodonti</a></li> <li>Class †<a href="/wiki/Anaspida" title="Anaspida">Anaspida</a></li> <li>Class †<a href="/wiki/Cephalaspidomorphi" title="Cephalaspidomorphi">Cephalaspidomorphi</a></li></ul></li> <li>Infraphylum <b><a href="/wiki/Gnathostomata" title="Gnathostomata">Gnathostomata</a></b> (<a href="/wiki/Jaw" title="Jaw">jawed</a> vertebrates) <ul><li>Class †<b><a href="/wiki/Placodermi" class="mw-redirect" title="Placodermi">Placodermi</a></b> (Paleozoic armoured forms; paraphyletic in relation to all other gnathostomes)</li> <li>Class <b><a href="/wiki/Chondrichthyes" title="Chondrichthyes">Chondrichthyes</a></b> (cartilaginous fish; 900+ species)</li> <li>Class †<b><a href="/wiki/Acanthodii" title="Acanthodii">Acanthodii</a></b> (Paleozoic "spiny sharks"; paraphyletic in relation to Chondrichthyes)</li> <li>Class <b><a href="/wiki/Osteichthyes" title="Osteichthyes">Osteichthyes</a></b> (bony fish; 30,000+ species) <ul><li>Subclass <b><a href="/wiki/Actinopterygii" title="Actinopterygii">Actinopterygii</a></b> (ray-finned fish; about 30,000 species)</li> <li>Subclass <b><a href="/wiki/Sarcopterygii" title="Sarcopterygii">Sarcopterygii</a></b> (lobe-finned fish: 8 species; paraphyletic when tetrapods are excluded)</li></ul></li></ul></li> <li>Superclass <b><a href="/wiki/Tetrapoda" class="mw-redirect" title="Tetrapoda">Tetrapoda</a></b> (four-limbed vertebrates; 35,100+ species)<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>a<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> <ul><li>Class <b><a href="/wiki/Amphibian" title="Amphibian">Amphibia</a></b> (amphibians; 8,100+ species)<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup></li> <li>Class <b><a href="/wiki/Sauropsida" title="Sauropsida">Sauropsida</a></b> (<a href="/wiki/Reptile" title="Reptile">reptiles</a> (including <a href="/wiki/Bird" title="Bird">birds</a>); 21,300+ species – 10,000+ species of birds and 11,300+ species of reptiles)<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup></li> <li>Class <b><a href="/wiki/Synapsida" title="Synapsida">Synapsida</a></b> (<a href="/wiki/Mammal" title="Mammal">mammals</a>; 5,700+ species)</li></ul></li></ul></li></ul></li></ul> <div class="mw-heading mw-heading2"><h2 id="Subphyla">Subphyla</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=4" title="Edit section: Subphyla"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/List_of_chordate_orders" title="List of chordate orders">List of chordate orders</a></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Branchiostoma_lanceolatum.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/47/Branchiostoma_lanceolatum.jpg/250px-Branchiostoma_lanceolatum.jpg" decoding="async" width="220" height="174" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/47/Branchiostoma_lanceolatum.jpg/330px-Branchiostoma_lanceolatum.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/47/Branchiostoma_lanceolatum.jpg/500px-Branchiostoma_lanceolatum.jpg 2x" data-file-width="1024" data-file-height="811" /></a><figcaption> Cephalochordate: lancelet. Pictured species: <i><a href="/wiki/Branchiostoma_lanceolatum" title="Branchiostoma lanceolatum">Branchiostoma lanceolatum</a></i></figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Cephalochordata:_Lancelets">Cephalochordata: Lancelets</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=5" title="Edit section: Cephalochordata: Lancelets"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Lancelet" title="Lancelet">Lancelet</a></div> <p><a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">Cephalochordates</a>, one of the three subdivisions of chordates, are small, "vaguely fish-shaped" animals that lack brains, clearly defined heads and specialized sense organs.<sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> These burrowing filter-feeders compose the earliest-branching chordate subphylum.<sup id="cite_ref-Gee2008AmphioxusUnleashed_27-0" class="reference"><a href="#cite_note-Gee2008AmphioxusUnleashed-27"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Tunicata_(Urochordata)"><span id="Tunicata_.28Urochordata.29"></span>Tunicata (Urochordata)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=6" title="Edit section: Tunicata (Urochordata)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Tunicate" title="Tunicate">Tunicate (Urochordata)</a></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:BU_Bio.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cc/BU_Bio.jpg/220px-BU_Bio.jpg" decoding="async" width="220" height="181" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cc/BU_Bio.jpg/330px-BU_Bio.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/c/cc/BU_Bio.jpg 2x" data-file-width="432" data-file-height="356" /></a><figcaption>Tunicates: sea squirts</figcaption></figure> <p>The <a href="/wiki/Tunicates" class="mw-redirect" title="Tunicates">tunicates</a> have three distinct adult shapes. Each is a member of one of three monophylitic clades. All tunicate <a href="/wiki/Larva" title="Larva">larvae</a> have the standard chordate features, including long, <a href="/wiki/Tadpole" title="Tadpole">tadpole</a>-like tails. Their larva also have rudimentary brains, light sensors and tilt sensors.<sup id="cite_ref-Benton2002VertebratePalaeontologyP5_29-0" class="reference"><a href="#cite_note-Benton2002VertebratePalaeontologyP5-29"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p><p>The smallest of the three groups of tunicates is the <a href="/wiki/Larvacean" title="Larvacean">Appendicularia</a>. They retain tadpole-like shapes and active swimming all their lives, and were for a long time regarded as larvae of the other two groups.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> </p><p>The other two groups, the sea squirts and the salps, metamorphize into adult forms which lose the notochord, nerve cord, and post anal tail. Both are soft-bodied filter feeders with multiple gill slits. They feed on <a href="/wiki/Plankton" title="Plankton">plankton</a> which they collect in their mucus. </p><p>Sea squirts are <a href="/wiki/Sessility_(motility)" title="Sessility (motility)">sessile</a> and consist mainly of water pumps and filter-feeding apparatus.<sup id="cite_ref-Benton2002VertebratePalaeontologyP5_29-1" class="reference"><a href="#cite_note-Benton2002VertebratePalaeontologyP5-29"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> Most attach firmly to the sea floor, where they remain in one place for life, feeding on plankton. </p><p>The <a href="/wiki/Salp" title="Salp">salps</a> float in mid-water, feeding on <a href="/wiki/Plankton" title="Plankton">plankton</a>, and have a two-generation cycle in which one generation is solitary and the next forms chain-like <a href="/wiki/Colony_(biology)" title="Colony (biology)">colonies</a>.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> </p><p>The etymology of the term Urochordata (Balfour 1881) is from the ancient Greek οὐρά (oura, "tail") + Latin chorda ("cord"), because the notochord is only found in the tail.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> The term <b>Tunicata</b> (Lamarck 1816) is recognised as having precedence and is now more commonly used.<sup id="cite_ref-Benton2002VertebratePalaeontologyP5_29-2" class="reference"><a href="#cite_note-Benton2002VertebratePalaeontologyP5-29"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p> <style data-mw-deduplicate="TemplateStyles:r1273380762/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner span:not(.skin-invert-image):not(.skin-invert):not(.bg-transparent) img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner span:not(.skin-invert-image):not(.skin-invert):not(.bg-transparent) img{background-color:white}}</style><div class="thumb tmulti tnone center"><div class="thumbinner multiimageinner" style="width:324px;max-width:324px"><div class="trow"><div class="theader">Comparison of two invertebrate chordates</div></div><div class="trow"><div class="tsingle" style="width:322px;max-width:322px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Comparison_of_Three_Invertebrate_Chordates.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/44/Comparison_of_Three_Invertebrate_Chordates.svg/330px-Comparison_of_Three_Invertebrate_Chordates.svg.png" decoding="async" width="320" height="256" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/44/Comparison_of_Three_Invertebrate_Chordates.svg/500px-Comparison_of_Three_Invertebrate_Chordates.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/44/Comparison_of_Three_Invertebrate_Chordates.svg/640px-Comparison_of_Three_Invertebrate_Chordates.svg.png 2x" data-file-width="512" data-file-height="409" /></a></span></div><div class="thumbcaption text-align-center">A. Lancelet, B. Larval tunicate, C. Adult tunicate<br /><small>--------------------------------------------------------<br />1. <a href="/wiki/Notochord" title="Notochord">Notochord</a>, 2. Nerve chord, 3. Buccal <a href="/wiki/Cirrus_(biology)" title="Cirrus (biology)">cirri</a>, 4. <a href="/wiki/Pharynx" title="Pharynx">Pharynx</a>, 5. <a href="/wiki/Gill_slit" title="Gill slit">Gill slit</a>, 6. <a href="/wiki/Gonad" title="Gonad">Gonad</a>, 7. Gut, 8. V-shaped muscles, 9. Anus, 10. Inhalant <a href="/wiki/Syphon" class="mw-redirect" title="Syphon">syphon</a>, 11. Exhalant syphon, 12. Heart, 13. Stomach, 14. <a href="/wiki/Esophagus" title="Esophagus">Esophagus</a>, 15. Intestines, 16. Tail, 17. Atrium, 18. <a href="/wiki/Tunica_(biology)" title="Tunica (biology)">Tunic</a></small></div></div></div></div></div> <div class="mw-heading mw-heading3"><h3 id="Craniata_(Vertebrata)"><span id="Craniata_.28Vertebrata.29"></span>Craniata (Vertebrata)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=7" title="Edit section: Craniata (Vertebrata)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Main articles: <a href="/wiki/Craniata" class="mw-redirect" title="Craniata">Craniata</a> and <a href="/wiki/Vertebrata" class="mw-redirect" title="Vertebrata">Vertebrata</a></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Pacific_hagfish_Myxine.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/1/12/Pacific_hagfish_Myxine.jpg" decoding="async" width="199" height="149" class="mw-file-element" data-file-width="199" data-file-height="149" /></a><figcaption>Craniate: <a href="/wiki/Hagfish" title="Hagfish">hagfish</a></figcaption></figure> <p><a href="/wiki/Craniate" title="Craniate">Craniates</a> all have distinct <a href="/wiki/Skull" title="Skull">skulls</a>. They include the <a href="/wiki/Hagfish" title="Hagfish">hagfish</a>, which have no <a href="/wiki/Vertebra" title="Vertebra">vertebrae</a>. <a href="/wiki/Michael_Benton" title="Michael Benton">Michael J. Benton</a> commented that "craniates are characterized by their heads, just as chordates, or possibly all <a href="/wiki/Deuterostome" title="Deuterostome">deuterostomes</a>, are by their tails".<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> </p><p>Most craniates are <a href="/wiki/Vertebrate" title="Vertebrate">vertebrates</a>, in which the <a href="/wiki/Notochord" title="Notochord">notochord</a> is replaced by the <a href="/wiki/Vertebral_column" class="mw-redirect" title="Vertebral column">vertebral column</a>.<sup id="cite_ref-UCMPMorphologyOfVertebrates_34-0" class="reference"><a href="#cite_note-UCMPMorphologyOfVertebrates-34"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> It consists of a series of bony or cartilaginous <a href="/wiki/Cylinder" title="Cylinder">cylindrical</a> vertebrae, generally with <a href="/wiki/Neural_arch" class="mw-redirect" title="Neural arch">neural arches</a> that protect the <a href="/wiki/Spinal_cord" title="Spinal cord">spinal cord</a>, and with projections that link the vertebrae. <a href="/wiki/Hagfish" title="Hagfish">Hagfishes</a> have incomplete <a href="/wiki/Braincase" class="mw-redirect" title="Braincase">braincases</a> and no vertebrae, and are therefore not regarded as vertebrates,<sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> but they are members of the craniates, the group within which vertebrates are thought to have <a href="/wiki/Evolution" title="Evolution">evolved</a>.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> However the cladistic exclusion of hagfish from the vertebrates is controversial, as they may instead be degenerate vertebrates who have secondarily lost their vertebral columns.<sup id="cite_ref-r3_37-0" class="reference"><a href="#cite_note-r3-37"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p><p>Before <a href="/wiki/Molecular_phylogenetics" title="Molecular phylogenetics">molecular phylogenetics</a>, the position of <a href="/wiki/Lamprey" title="Lamprey">lampreys</a> was ambiguous. They have complete braincases and rudimentary vertebrae, and therefore may be regarded as vertebrates and true <a href="/wiki/Fish" title="Fish">fish</a>.<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> However, molecular phylogenetics, which uses <a href="/wiki/DNA" title="DNA">DNA</a> to classify organisms, has produced both results that group them with vertebrates and others that group them with hagfish.<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> If lampreys are more closely related to the hagfish than the other vertebrates, this would suggest that they form a <a href="/wiki/Clade" title="Clade">clade</a>, which has been named the <a href="/wiki/Cyclostomata" class="mw-redirect" title="Cyclostomata">Cyclostomata</a>.<sup id="cite_ref-Delarbre_2002_40-0" class="reference"><a href="#cite_note-Delarbre_2002-40"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> </p><p><span class="anchor" id="Taxonomy"></span> </p> <div class="mw-heading mw-heading2"><h2 id="Phylogeny">Phylogeny</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=8" title="Edit section: Phylogeny"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Overview">Overview</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=9" title="Edit section: Overview"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Haikouichthys4.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/51/Haikouichthys4.png/220px-Haikouichthys4.png" decoding="async" width="220" height="66" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/51/Haikouichthys4.png/330px-Haikouichthys4.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/51/Haikouichthys4.png/440px-Haikouichthys4.png 2x" data-file-width="500" data-file-height="150" /></a><figcaption><i><a href="/wiki/Haikouichthys" title="Haikouichthys">Haikouichthys</a></i>, from about <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=518">518</a> million years ago</span> in China, may be the earliest known fish.<sup id="cite_ref-ShuConwayMorrisHan2003Haikouichthys_41-0" class="reference"><a href="#cite_note-ShuConwayMorrisHan2003Haikouichthys-41"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>There is still much ongoing differential (DNA sequence based) comparison research that is trying to separate out the simplest forms of chordates. As some lineages of the 90% of species that lack a backbone or notochord might have lost these structures over time, this complicates the classification of chordates. Some chordate lineages may only be found by DNA analysis, when there is no physical trace of any chordate-like structures.<sup id="cite_ref-42" class="reference"><a href="#cite_note-42"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p>Attempts to work out the evolutionary relationships of the chordates have produced several hypotheses. The current consensus is that chordates are <a href="/wiki/Monophyletic" class="mw-redirect" title="Monophyletic">monophyletic</a>, meaning that the Chordata include all and only the descendants of a single common ancestor, which is itself a chordate, and that the <a href="/wiki/Vertebrate" title="Vertebrate">vertebrates</a>' nearest relatives are tunicates. Recent identification of two <a href="/wiki/Conserved_signature_indels" title="Conserved signature indels">conserved signature indels</a> (CSIs) in the proteins cyclophilin-like protein and mitochondrial inner membrane protease ATP23, which are exclusively shared by all vertebrates, <a href="/wiki/Tunicate" title="Tunicate">tunicates</a> and <a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">cephalochordates</a> also provide strong evidence of the monophyly of Chordata.<sup id="cite_ref-:0_9-1" class="reference"><a href="#cite_note-:0-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p><p>All of the earliest chordate <a href="/wiki/Fossil" title="Fossil">fossils</a> have been found in the Early <a href="/wiki/Cambrian" title="Cambrian">Cambrian</a> <a href="/wiki/Chengjiang_fauna" class="mw-redirect" title="Chengjiang fauna">Chengjiang fauna</a>, and include two species that are regarded as <a href="/wiki/Fish" title="Fish">fish</a>, which implies that they are vertebrates. Because the fossil record of early chordates is poor, only <a href="/wiki/Molecular_phylogenetics" title="Molecular phylogenetics">molecular phylogenetics</a> offers a reasonable prospect of dating their emergence. However, the use of molecular phylogenetics for dating evolutionary transitions is controversial. It has proven difficult to produce a detailed classification within the living chordates. Attempts to produce evolutionary "<a href="/wiki/Phylogenetic_tree" title="Phylogenetic tree">family trees</a>" shows that many of the traditional <a href="/wiki/Class_(biology)" title="Class (biology)">classes</a> are <a href="/wiki/Paraphyletic" class="mw-redirect" title="Paraphyletic">paraphyletic</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (December 2024)">citation needed</span></a></i>]</sup> </p> <div style="float:right; width:auto; border:solid 1px silver; padding:2px; margin:2px"> <div style="width:auto; border:solid 1px silver; padding:5px"> <div class="clade"><style data-mw-deduplicate="TemplateStyles:r1261294616">body.skin-vector-2022 .mw-parser-output div.clade,body.skin-minerva .mw-parser-output div.clade{overflow-x:auto;overflow-y:hidden}body.skin-minerva .mw-parser-output div.clade p{font-size:inherit}.mw-parser-output table.clade{border-spacing:0;margin:0;font-size:100%;line-height:100%;border-collapse:separate;width:auto;display:table}.mw-parser-output table.clade table.clade{width:100%;line-height:inherit}.mw-parser-output table.clade td.clade-label{min-width:0.2em;width:0.2em;padding:0.1em 0.25em;vertical-align:bottom;text-align:center;border-left:1px solid;border-bottom:1px solid;white-space:nowrap}.mw-parser-output table.clade td.clade-label::before,.mw-parser-output table.clade td.clade-slabel::before{content:"\2060 "}.mw-parser-output table.clade td.clade-fixed-width{overflow:hidden;text-overflow:ellipsis}.mw-parser-output table.clade td.clade-fixed-width:hover{overflow:visible}.mw-parser-output table.clade td.clade-label.first{border-left:none;border-right:none}.mw-parser-output table.clade td.clade-label.reverse{border-left:none;border-right:1px solid}.mw-parser-output table.clade td.clade-slabel{padding:0.1em 0.25em;vertical-align:top;text-align:center;border-left:1px solid;white-space:nowrap}.mw-parser-output table.clade td.clade-slabel:hover{overflow:visible}.mw-parser-output table.clade td.clade-slabel.last{border-left:none;border-right:none}.mw-parser-output table.clade td.clade-slabel.reverse{border-left:none;border-right:1px solid}.mw-parser-output table.clade td.clade-bar{vertical-align:middle;text-align:left;padding:0 0.5em;position:relative}.mw-parser-output table.clade td.clade-bar.reverse{text-align:right;position:relative}.mw-parser-output table.clade td.clade-leaf{border:0;padding:0;text-align:left}.mw-parser-output table.clade td.clade-leaf p{padding-right:5px;padding-left:2px}.mw-parser-output table.clade td.clade-leafR{border:0;padding:0;text-align:right}.mw-parser-output table.clade td.clade-leafR p{padding-left:5px;padding-right:2px}.mw-parser-output table.clade td.clade-leaf.reverse{text-align:right}.mw-parser-output table.clade td.clade-leaf.reverse p{padding-left:5px;padding-right:2px}.mw-parser-output table.clade:hover span.linkA{background-color:yellow}.mw-parser-output table.clade:hover span.linkB{background-color:green}</style> <table class="clade"> <tbody><tr> <td class="clade-label first"><a href="/wiki/Deuterostome" title="Deuterostome">Deuterostomes</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"><a href="/wiki/Ambulacraria" title="Ambulacraria">Ambulacraria</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Hemichordate" title="Hemichordate">Hemichordates</a> <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Ptychodera_flava_in_New_Caledonia,_Encyclopaedia_Britannica_(1911)_rotated.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/af/Ptychodera_flava_in_New_Caledonia%2C_Encyclopaedia_Britannica_%281911%29_rotated.png/60px-Ptychodera_flava_in_New_Caledonia%2C_Encyclopaedia_Britannica_%281911%29_rotated.png" decoding="async" width="45" height="20" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/af/Ptychodera_flava_in_New_Caledonia%2C_Encyclopaedia_Britannica_%281911%29_rotated.png/120px-Ptychodera_flava_in_New_Caledonia%2C_Encyclopaedia_Britannica_%281911%29_rotated.png 1.5x" data-file-width="1064" data-file-height="480" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Echinoderm" title="Echinoderm">Echinoderms</a> <span typeof="mw:File"><a href="/wiki/File:Starfish_(PSF).png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2d/Starfish_%28PSF%29.png/30px-Starfish_%28PSF%29.png" decoding="async" width="30" height="31" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2d/Starfish_%28PSF%29.png/45px-Starfish_%28PSF%29.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2d/Starfish_%28PSF%29.png/60px-Starfish_%28PSF%29.png 2x" data-file-width="1702" data-file-height="1749" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><b>Chordates</b> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">Cephalochordates</a> <span typeof="mw:File"><a href="/wiki/File:Branchiostoma_cultellus.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Branchiostoma_cultellus.jpg/120px-Branchiostoma_cultellus.jpg" decoding="async" width="75" height="20" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Branchiostoma_cultellus.jpg/250px-Branchiostoma_cultellus.jpg 2x" data-file-width="1300" data-file-height="341" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Olfactores" title="Olfactores">Olfactores</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Tunicate" title="Tunicate">Tunicates</a> <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:PSM_V44_D080_Salpa.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/PSM_V44_D080_Salpa.jpg/35px-PSM_V44_D080_Salpa.jpg" decoding="async" width="35" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/PSM_V44_D080_Salpa.jpg/53px-PSM_V44_D080_Salpa.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c1/PSM_V44_D080_Salpa.jpg/70px-PSM_V44_D080_Salpa.jpg 2x" data-file-width="907" data-file-height="455" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Vertebrate" title="Vertebrate">Vertebrates</a> <span typeof="mw:File"><a href="/wiki/File:Ichthyostega_BW_(flipped).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/89/Ichthyostega_BW_%28flipped%29.jpg/70px-Ichthyostega_BW_%28flipped%29.jpg" decoding="async" width="70" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/89/Ichthyostega_BW_%28flipped%29.jpg/105px-Ichthyostega_BW_%28flipped%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/89/Ichthyostega_BW_%28flipped%29.jpg/140px-Ichthyostega_BW_%28flipped%29.jpg 2x" data-file-width="727" data-file-height="244" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </div>Diagram of the <a href="/wiki/Cladogram" title="Cladogram">evolutionary relationships</a> of chordates<sup id="cite_ref-Ruppert2005_14-1" class="reference"><a href="#cite_note-Ruppert2005-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup></div> <p>While this has been well known since the 19th century, an insistence on only monophyletic taxa has resulted in vertebrate classification being in a state of flux.<sup id="cite_ref-43" class="reference"><a href="#cite_note-43"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> </p><p>The majority of animals more complex than <a href="/wiki/Jellyfish" title="Jellyfish">jellyfish</a> and other <a href="/wiki/Cnidarians" class="mw-redirect" title="Cnidarians">cnidarians</a> are split into two groups, the <a href="/wiki/Protostome" title="Protostome">protostomes</a> and <a href="/wiki/Deuterostome" title="Deuterostome">deuterostomes</a>, the latter of which contains chordates.<sup id="cite_ref-Erwin20002_44-0" class="reference"><a href="#cite_note-Erwin20002-44"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> It seems very likely the <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=555">555</a> million-year-old</span> <i><a href="/wiki/Kimberella" title="Kimberella">Kimberella</a></i> was a member of the protostomes.<sup id="cite_ref-Fedonkin2007_45-0" class="reference"><a href="#cite_note-Fedonkin2007-45"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Butterfield2006_46-0" class="reference"><a href="#cite_note-Butterfield2006-46"><span class="cite-bracket">[</span>45<span class="cite-bracket">]</span></a></sup> If so, this means the protostome and deuterostome lineages must have split some time before <i>Kimberella</i> appeared—at least <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=558">558</a> million years ago</span>, and hence well before the start of the Cambrian <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=538.8">538.8</a> million years ago</span>.<sup id="cite_ref-Erwin20002_44-1" class="reference"><a href="#cite_note-Erwin20002-44"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> Three enigmatic species that are possible very early tunicates, and therefore deuterostomes, were also found from the <a href="/wiki/Ediacaran" title="Ediacaran">Ediacaran</a> period – <i><a href="/wiki/Ausia_(animal)" class="mw-redirect" title="Ausia (animal)">Ausia fenestrata</a></i> from the Nama Group of <a href="/wiki/Namibia" title="Namibia">Namibia</a>, the sac-like <i><a href="/wiki/Yarnemia" title="Yarnemia">Yarnemia ascidiformis</a></i>, and one from a second new <i>Ausia</i>-like genus from the Onega Peninsula of northern <a href="/wiki/Russia" title="Russia">Russia</a>, <i><a href="/wiki/Burykhia" title="Burykhia">Burykhia hunti</a></i>. Results of a new study have shown possible affinity of these Ediacaran organisms to the ascidians.<sup id="cite_ref-Vickers-Rich_47-0" class="reference"><a href="#cite_note-Vickers-Rich-47"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Oslo_2008_48-0" class="reference"><a href="#cite_note-Oslo_2008-48"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup> <i>Ausia</i> and <i>Burykhia</i> lived in shallow coastal waters slightly more than 555 to 548 million years ago, and are believed to be the oldest evidence of the chordate lineage of metazoans.<sup id="cite_ref-Oslo_2008_48-1" class="reference"><a href="#cite_note-Oslo_2008-48"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup> The Russian Precambrian fossil <i><a href="/wiki/Yarnemia" title="Yarnemia">Yarnemia</a></i> is identified as a tunicate only tentatively, because its fossils are nowhere near as well-preserved as those of <i>Ausia</i> and <i>Burykhia</i>, so this identification has been questioned. </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:BlueWhaleSkeleton.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/14/BlueWhaleSkeleton.jpg/220px-BlueWhaleSkeleton.jpg" decoding="async" width="220" height="106" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/14/BlueWhaleSkeleton.jpg/330px-BlueWhaleSkeleton.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/14/BlueWhaleSkeleton.jpg/440px-BlueWhaleSkeleton.jpg 2x" data-file-width="708" data-file-height="341" /></a><figcaption>A skeleton of the <a href="/wiki/Blue_whale" title="Blue whale">blue whale</a>, the largest animal, extant or extinct, ever discovered. Mounted outside the Long Marine Laboratory at the <a href="/wiki/University_of_California,_Santa_Cruz" title="University of California, Santa Cruz">University of California, Santa Cruz</a>. The largest blue whale ever reliably recorded measured 98ft (30m) long.</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Peregrine_Falcon_12.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/dc/Peregrine_Falcon_12.jpg/220px-Peregrine_Falcon_12.jpg" decoding="async" width="220" height="233" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/dc/Peregrine_Falcon_12.jpg/330px-Peregrine_Falcon_12.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/dc/Peregrine_Falcon_12.jpg/440px-Peregrine_Falcon_12.jpg 2x" data-file-width="2530" data-file-height="2685" /></a><figcaption>A <a href="/wiki/Peregrine_falcon" title="Peregrine falcon">peregrine falcon</a>, the world's fastest animal. Peregrines use gravity and aerodynamics to achieve their top speed of around 242mph (390km/h), as opposed to locomotion.</figcaption></figure> <p>Fossils of one major deuterostome group, the <a href="/wiki/Echinoderm" title="Echinoderm">echinoderms</a> (whose modern members include <a href="/wiki/Starfish" title="Starfish">starfish</a>, <a href="/wiki/Sea_urchin" title="Sea urchin">sea urchins</a> and <a href="/wiki/Crinoid" title="Crinoid">crinoids</a>), are quite common from the start of the Cambrian, <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=542">542</a> million years ago</span>.<sup id="cite_ref-Bengtson2004_49-0" class="reference"><a href="#cite_note-Bengtson2004-49"><span class="cite-bracket">[</span>48<span class="cite-bracket">]</span></a></sup> The Mid <a href="/wiki/Cambrian" title="Cambrian">Cambrian</a> fossil <i><a href="/wiki/Rhabdotubus_johanssoni" class="mw-redirect" title="Rhabdotubus johanssoni">Rhabdotubus johanssoni</a></i> has been interpreted as a <a href="/wiki/Pterobranch" class="mw-redirect" title="Pterobranch">pterobranch</a> hemichordate.<sup id="cite_ref-50" class="reference"><a href="#cite_note-50"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> Opinions differ about whether the <a href="/wiki/Chengjiang_fauna" class="mw-redirect" title="Chengjiang fauna">Chengjiang fauna</a> fossil <i><a href="/wiki/Yunnanozoon" title="Yunnanozoon">Yunnanozoon</a></i>, from the earlier Cambrian, was a hemichordate or chordate.<sup id="cite_ref-ChenHangLi1996_51-0" class="reference"><a href="#cite_note-ChenHangLi1996-51"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ChenHangLi1999_52-0" class="reference"><a href="#cite_note-ChenHangLi1999-52"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup> Another fossil, <i><a href="/wiki/Haikouella_lanceolata" class="mw-redirect" title="Haikouella lanceolata">Haikouella lanceolata</a></i>, also from the Chengjiang fauna, is interpreted as a chordate and possibly a craniate, as it shows signs of a heart, arteries, gill filaments, a tail, a neural chord with a brain at the front end, and possibly eyes—although it also had short tentacles round its mouth.<sup id="cite_ref-ChenHangLi1999_52-1" class="reference"><a href="#cite_note-ChenHangLi1999-52"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup> <i><a href="/wiki/Haikouichthys" title="Haikouichthys">Haikouichthys</a></i> and <i><a href="/wiki/Myllokunmingia" title="Myllokunmingia">Myllokunmingia</a></i>, also from the Chengjiang fauna, are regarded as <a href="/wiki/Fish" title="Fish">fish</a>.<sup id="cite_ref-ShuConwayMorrisHan2003Haikouichthys_41-1" class="reference"><a href="#cite_note-ShuConwayMorrisHan2003Haikouichthys-41"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-53" class="reference"><a href="#cite_note-53"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> <i><a href="/wiki/Pikaia" title="Pikaia">Pikaia</a></i>, discovered much earlier (1911) but from the Mid Cambrian <a href="/wiki/Burgess_Shale" title="Burgess Shale">Burgess Shale</a> (505 Ma), is also regarded as a primitive chordate.<sup id="cite_ref-54" class="reference"><a href="#cite_note-54"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup> On the other hand, fossils of early chordates are very rare, since invertebrate chordates have no bones or teeth, and only one has been reported for the rest of the Cambrian.<sup id="cite_ref-ConwayMorris2008Metaspriggina_55-0" class="reference"><a href="#cite_note-ConwayMorris2008Metaspriggina-55"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> The best known and earliest unequivocally identified Tunicate is <i><a href="/wiki/Shankouclava" title="Shankouclava">Shankouclava shankouense</a></i> from the Lower <a href="/wiki/Cambrian" title="Cambrian">Cambrian</a> <a href="/wiki/Maotianshan_Shale" class="mw-redirect" title="Maotianshan Shale">Maotianshan Shale</a> at Shankou village, Anning, near <a href="/wiki/Kunming" title="Kunming">Kunming</a> (<a href="/wiki/Northern_and_southern_China" title="Northern and southern China">South China</a>).<sup id="cite_ref-Jun-Yuan2003_56-0" class="reference"><a href="#cite_note-Jun-Yuan2003-56"><span class="cite-bracket">[</span>55<span class="cite-bracket">]</span></a></sup> </p><p>The evolutionary relationships between the chordate groups and between chordates as a whole and their closest deuterostome relatives have been debated since 1890. Studies based on anatomical, <a href="/wiki/Embryology" title="Embryology">embryological</a>, and paleontological data have produced different "family trees". Some closely linked chordates and hemichordates, but that idea is now rejected.<sup id="cite_ref-Ruppert2005_14-2" class="reference"><a href="#cite_note-Ruppert2005-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> Combining such analyses with data from a small set of <a href="/wiki/Ribosome" title="Ribosome">ribosome</a> <a href="/wiki/RNA" title="RNA">RNA</a> genes eliminated some older ideas, but opened up the possibility that tunicates (urochordates) are "basal deuterostomes", surviving members of the group from which echinoderms, hemichordates and chordates evolved.<sup id="cite_ref-WinchellSullivanCameronSwallaMallatt2002_57-0" class="reference"><a href="#cite_note-WinchellSullivanCameronSwallaMallatt2002-57"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup> Some researchers believe that, within the chordates, craniates are most closely related to cephalochordates, but there are also reasons for regarding tunicates (urochordates) as craniates' closest relatives.<sup id="cite_ref-Ruppert2005_14-3" class="reference"><a href="#cite_note-Ruppert2005-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-BlairHedges2005_58-0" class="reference"><a href="#cite_note-BlairHedges2005-58"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> </p><p>Since early chordates have left a poor fossil record, attempts have been made to calculate the key dates in their evolution by <a href="/wiki/Molecular_phylogenetics" title="Molecular phylogenetics">molecular phylogenetics</a> techniques—by analyzing biochemical differences, mainly in RNA. One such study suggested that deuterostomes arose before <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=900">900</a> million years ago</span> and the earliest chordates around <span class="nourlexpansion plainlinks" style="white-space:nowrap;"><a rel="nofollow" class="external text" href="https://geoltime.github.io/?Ma=896">896</a> million years ago</span>.<sup id="cite_ref-BlairHedges2005_58-1" class="reference"><a href="#cite_note-BlairHedges2005-58"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> However, molecular estimates of dates often disagree with each other and with the fossil record,<sup id="cite_ref-BlairHedges2005_58-2" class="reference"><a href="#cite_note-BlairHedges2005-58"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> and their assumption that the <a href="/wiki/Molecular_clock" title="Molecular clock">molecular clock</a> runs at a known constant rate has been challenged.<sup id="cite_ref-Ayala1999MolClockMirages_59-0" class="reference"><a href="#cite_note-Ayala1999MolClockMirages-59"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-SchwartzMaresca20006DoMolClocksRun_60-0" class="reference"><a href="#cite_note-SchwartzMaresca20006DoMolClocksRun-60"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> </p><p>Traditionally, Cephalochordata and Craniata were grouped into the proposed clade "Euchordata", which would have been the sister group to Tunicata/Urochordata. More recently, Cephalochordata has been thought of as a sister group to the "Olfactores", which includes the craniates and tunicates. The matter is not yet settled. </p><p>A specific relationship between vertebrates and <a href="/wiki/Tunicate" title="Tunicate">tunicates</a> is also strongly supported by two CSIs found in the proteins predicted exosome complex RRP44 and serine palmitoyltransferase, that are exclusively shared by species from these two subphyla but not <a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">cephalochordates</a>, indicating vertebrates are more closely related to tunicates than cephalochordates.<sup id="cite_ref-:0_9-2" class="reference"><a href="#cite_note-:0-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Cladogram">Cladogram</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=10" title="Edit section: Cladogram"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Below is a <a href="/wiki/Phylogenetic_tree" title="Phylogenetic tree">phylogenetic tree</a> of the phylum. Lines of the <a href="/wiki/Cladogram" title="Cladogram">cladogram</a> show probable evolutionary relationships between both <a href="/wiki/Extinct" class="mw-redirect" title="Extinct">extinct</a> taxa, which are denoted with a <a href="/wiki/Dagger_(mark)" title="Dagger (mark)">dagger</a> (†), and <a href="/wiki/Extant_taxa" class="mw-redirect" title="Extant taxa">extant taxa</a>.<sup id="cite_ref-61" class="reference"><a href="#cite_note-61"><span class="cite-bracket">[</span>60<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-62" class="reference"><a href="#cite_note-62"><span class="cite-bracket">[</span>61<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-63" class="reference"><a href="#cite_note-63"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-64" class="reference"><a href="#cite_note-64"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-65" class="reference"><a href="#cite_note-65"><span class="cite-bracket">[</span>64<span class="cite-bracket">]</span></a></sup> </p> <div class="clade"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"><b>Chordata</b> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Cephalochordata" class="mw-redirect" title="Cephalochordata">Cephalochordata</a> (lancelets) <span typeof="mw:File"><a href="/wiki/File:Branchiostoma_lanceolatum_(Amphioxus_lanceolatus).png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Branchiostoma_lanceolatum_%28Amphioxus_lanceolatus%29.png/70px-Branchiostoma_lanceolatum_%28Amphioxus_lanceolatus%29.png" decoding="async" width="70" height="7" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Branchiostoma_lanceolatum_%28Amphioxus_lanceolatus%29.png/105px-Branchiostoma_lanceolatum_%28Amphioxus_lanceolatus%29.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Branchiostoma_lanceolatum_%28Amphioxus_lanceolatus%29.png/140px-Branchiostoma_lanceolatum_%28Amphioxus_lanceolatus%29.png 2x" data-file-width="11456" data-file-height="1200" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Olfactores" title="Olfactores">Olfactores</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"><a href="/wiki/Tunicata" class="mw-redirect" title="Tunicata">Tunicata</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Larvacean" title="Larvacean">Appendicularia</a> (larvaceans) <span typeof="mw:File"><a href="/wiki/File:Oikopleura_dioica.tif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f3/Oikopleura_dioica.tif/lossy-page1-30px-Oikopleura_dioica.tif.jpg" decoding="async" width="30" height="34" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f3/Oikopleura_dioica.tif/lossy-page1-45px-Oikopleura_dioica.tif.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f3/Oikopleura_dioica.tif/lossy-page1-60px-Oikopleura_dioica.tif.jpg 2x" data-file-width="1468" data-file-height="1648" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label">Acopa </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Thaliacea" title="Thaliacea">Thaliacea</a> <span typeof="mw:File"><a href="/wiki/File:PSM_V44_D080_Salpa.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/PSM_V44_D080_Salpa.jpg/35px-PSM_V44_D080_Salpa.jpg" decoding="async" width="35" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/PSM_V44_D080_Salpa.jpg/53px-PSM_V44_D080_Salpa.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c1/PSM_V44_D080_Salpa.jpg/70px-PSM_V44_D080_Salpa.jpg 2x" data-file-width="907" data-file-height="455" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label">Enterogona </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf" style="border-right:2px solid red;border-bottom:0;border-top:2px solid red;"> <p><a href="/wiki/Phlebobranchia" title="Phlebobranchia">Phlebobranchia</a> <span typeof="mw:File"><a href="/wiki/File:Natural_History_-_Mollusca_-_Ascidia_virginea.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/74/Natural_History_-_Mollusca_-_Ascidia_virginea.png/40px-Natural_History_-_Mollusca_-_Ascidia_virginea.png" decoding="async" width="35" height="31" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/74/Natural_History_-_Mollusca_-_Ascidia_virginea.png/60px-Natural_History_-_Mollusca_-_Ascidia_virginea.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/74/Natural_History_-_Mollusca_-_Ascidia_virginea.png/120px-Natural_History_-_Mollusca_-_Ascidia_virginea.png 2x" data-file-width="937" data-file-height="820" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf" style="border-right:2px solid red;border-bottom:0;border-top:0;"> <p><a href="/wiki/Aplousobranchia" title="Aplousobranchia">Aplousobranchia</a> <span typeof="mw:File"><a href="/wiki/File:Didemnum_molle.jpeg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/04/Didemnum_molle.jpeg/40px-Didemnum_molle.jpeg" decoding="async" width="40" height="30" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/04/Didemnum_molle.jpeg/60px-Didemnum_molle.jpeg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/04/Didemnum_molle.jpeg/120px-Didemnum_molle.jpeg 2x" data-file-width="800" data-file-height="600" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td> <td rowspan="2" class="clade-bar" style="">"<a href="/wiki/Ascidiacea" title="Ascidiacea">Ascidiacea</a>" (<a href="/wiki/Paraphyletic" class="mw-redirect" title="Paraphyletic">paraphyletic</a>) </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf" style="border-right:2px solid red;border-bottom:2px solid red;border-top:0;"> <p><a href="/wiki/Stolidobranchia" title="Stolidobranchia">Stolidobranchia</a> <span typeof="mw:File"><a href="/wiki/File:Tunicate_komodo.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Tunicate_komodo.jpg/40px-Tunicate_komodo.jpg" decoding="async" width="40" height="30" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Tunicate_komodo.jpg/60px-Tunicate_komodo.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Tunicate_komodo.jpg/80px-Tunicate_komodo.jpg 2x" data-file-width="1680" data-file-height="1260" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Vertebrata" class="mw-redirect" title="Vertebrata">Vertebrata</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Myllokunmingiida" class="mw-redirect" title="Myllokunmingiida">Myllokunmingiida</a> † <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Haikouichthys_NT.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5b/Haikouichthys_NT.jpg/50px-Haikouichthys_NT.jpg" decoding="async" width="50" height="20" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5b/Haikouichthys_NT.jpg/75px-Haikouichthys_NT.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5b/Haikouichthys_NT.jpg/100px-Haikouichthys_NT.jpg 2x" data-file-width="567" data-file-height="228" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Anaspidomorphi" title="Anaspidomorphi">Anaspidomorphi</a> † <span typeof="mw:File"><a href="/wiki/File:Estonian_Museum_of_Natural_History_-_Birkenia.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Estonian_Museum_of_Natural_History_-_Birkenia.png/40px-Estonian_Museum_of_Natural_History_-_Birkenia.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Estonian_Museum_of_Natural_History_-_Birkenia.png/60px-Estonian_Museum_of_Natural_History_-_Birkenia.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c4/Estonian_Museum_of_Natural_History_-_Birkenia.png/120px-Estonian_Museum_of_Natural_History_-_Birkenia.png 2x" data-file-width="2350" data-file-height="2350" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Conodont" title="Conodont">Conodonta</a> † <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Conodonta.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Conodonta.png/120px-Conodonta.png" decoding="async" width="70" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Conodonta.png/250px-Conodonta.png 2x" data-file-width="3776" data-file-height="1217" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Cyclostomi" title="Cyclostomi">Cyclostomi</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Myxini" class="mw-redirect" title="Myxini">Myxini</a> (hagfish) <span typeof="mw:File"><a href="/wiki/File:Myxine_glutinosa_Gervais.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/dc/Myxine_glutinosa_Gervais.jpg/60px-Myxine_glutinosa_Gervais.jpg" decoding="async" width="50" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/dc/Myxine_glutinosa_Gervais.jpg/120px-Myxine_glutinosa_Gervais.jpg 1.5x" data-file-width="1200" data-file-height="429" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Hyperoartia" class="mw-redirect" title="Hyperoartia">Hyperoartia</a> (lampreys) <span typeof="mw:File"><a href="/wiki/File:Flussneunauge.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f5/Flussneunauge.jpg/60px-Flussneunauge.jpg" decoding="async" width="50" height="25" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f5/Flussneunauge.jpg/120px-Flussneunauge.jpg 1.5x" data-file-width="550" data-file-height="270" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Pteraspidomorphi" title="Pteraspidomorphi">Pteraspidomorphi</a> † <span typeof="mw:File"><a href="/wiki/File:Astraspis_desiderata.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7d/Astraspis_desiderata.png/30px-Astraspis_desiderata.png" decoding="async" width="30" height="21" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7d/Astraspis_desiderata.png/45px-Astraspis_desiderata.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7d/Astraspis_desiderata.png/60px-Astraspis_desiderata.png 2x" data-file-width="354" data-file-height="250" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Thelodonti" title="Thelodonti">Thelodonti</a> † <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Sphenonectris_turnerae_-_MUSE.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/20/Sphenonectris_turnerae_-_MUSE.jpg/40px-Sphenonectris_turnerae_-_MUSE.jpg" decoding="async" width="40" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/20/Sphenonectris_turnerae_-_MUSE.jpg/60px-Sphenonectris_turnerae_-_MUSE.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/20/Sphenonectris_turnerae_-_MUSE.jpg/120px-Sphenonectris_turnerae_-_MUSE.jpg 2x" data-file-width="1824" data-file-height="1044" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf" style="border-right:2px solid blue;border-bottom:0;border-top:2px solid blue;"> <p><a href="/wiki/Galeaspida" title="Galeaspida">Galeaspida</a> † <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:A_Galeaspid.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cc/A_Galeaspid.jpg/40px-A_Galeaspid.jpg" decoding="async" width="40" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cc/A_Galeaspid.jpg/60px-A_Galeaspid.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cc/A_Galeaspid.jpg/80px-A_Galeaspid.jpg 2x" data-file-width="442" data-file-height="429" /></a></span></span> </p> </td> <td rowspan="2" class="clade-bar" style="">"<a href="/wiki/Cephalaspidomorphi" title="Cephalaspidomorphi">Cephalaspidomorphi</a>" (paraphyletic) </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf" style="border-right:2px solid blue;border-bottom:0;border-top:0;"> <p><a href="/wiki/Pituriaspida" title="Pituriaspida">Pituriaspida</a> † <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Pituriaspida.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Pituriaspida.gif/40px-Pituriaspida.gif" decoding="async" width="40" height="25" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Pituriaspida.gif/60px-Pituriaspida.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f6/Pituriaspida.gif/120px-Pituriaspida.gif 2x" data-file-width="375" data-file-height="237" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf" style="border-right:2px solid blue;border-bottom:2px solid blue;border-top:0;"> <p><a href="/wiki/Osteostraci" title="Osteostraci">Osteostraci</a> † <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Tremataspis_NT_small.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/06/Tremataspis_NT_small.jpg/60px-Tremataspis_NT_small.jpg" decoding="async" width="50" height="38" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/06/Tremataspis_NT_small.jpg/120px-Tremataspis_NT_small.jpg 1.5x" data-file-width="600" data-file-height="450" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Gnathostomata" title="Gnathostomata">Gnathostomata</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first" style="border-left:none;border-right:none;border-bottom:3px double;"> </td> <td rowspan="2" class="clade-leaf"> <p>"<a href="/wiki/Placodermi" class="mw-redirect" title="Placodermi">Placodermi</a>" † (paraphyletic) <span typeof="mw:File"><a href="/wiki/File:Dunkleosteus_terrelli_2024_reconstruction.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/55/Dunkleosteus_terrelli_2024_reconstruction.jpg/120px-Dunkleosteus_terrelli_2024_reconstruction.jpg" decoding="async" width="70" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/55/Dunkleosteus_terrelli_2024_reconstruction.jpg/250px-Dunkleosteus_terrelli_2024_reconstruction.jpg 2x" data-file-width="700" data-file-height="385" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel" style="border-right:none;border-left:1px solid;"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first" style="border-left:none;border-right:none;border-bottom:3px double;"> </td> <td rowspan="2" class="clade-leaf"> <p>"<a href="/wiki/Acanthodii" title="Acanthodii">Acanthodii</a>" † (paraphyletic) <span typeof="mw:File"><a href="/wiki/File:Acanthodes_BW.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Acanthodes_BW.jpg/60px-Acanthodes_BW.jpg" decoding="async" width="60" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Acanthodes_BW.jpg/90px-Acanthodes_BW.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Acanthodes_BW.jpg/120px-Acanthodes_BW.jpg 2x" data-file-width="800" data-file-height="303" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel" style="border-right:none;border-left:1px solid;"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Chondrichthyes" title="Chondrichthyes">Chondrichthyes</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Holocephali" title="Holocephali">Holocephali</a> <span typeof="mw:File"><a href="/wiki/File:Chimaera_monstrosa1.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Chimaera_monstrosa1.jpg/60px-Chimaera_monstrosa1.jpg" decoding="async" width="50" height="24" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1a/Chimaera_monstrosa1.jpg/120px-Chimaera_monstrosa1.jpg 1.5x" data-file-width="1148" data-file-height="552" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Elasmobranchii" title="Elasmobranchii">Elasmobranchii</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Selachimorpha" class="mw-redirect" title="Selachimorpha">Selachimorpha</a> (sharks) <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:White_shark_(Duane_Raver).png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/14/White_shark_%28Duane_Raver%29.png/60px-White_shark_%28Duane_Raver%29.png" decoding="async" width="50" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/14/White_shark_%28Duane_Raver%29.png/120px-White_shark_%28Duane_Raver%29.png 1.5x" data-file-width="756" data-file-height="352" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Batoidea" class="mw-redirect" title="Batoidea">Batoidea</a> (rays) <span typeof="mw:File"><a href="/wiki/File:Sawfish_logo.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/33/Sawfish_logo.png/50px-Sawfish_logo.png" decoding="async" width="50" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/33/Sawfish_logo.png/75px-Sawfish_logo.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/33/Sawfish_logo.png/100px-Sawfish_logo.png 2x" data-file-width="417" data-file-height="115" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Osteichthyes" title="Osteichthyes">Osteichthyes</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"><a href="/wiki/Actinopterygii" title="Actinopterygii">Actinopterygii</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Cladistia" title="Cladistia">Cladistia</a> <span typeof="mw:File"><a href="/wiki/File:Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/46/Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg/50px-Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg" decoding="async" width="50" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/46/Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg/75px-Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/46/Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg/100px-Polypterus_endlicherii_MHNT_ICHT_1995_8.jpg 2x" data-file-width="5197" data-file-height="1890" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Actinopteri" title="Actinopteri">Actinopteri</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Chondrostei" title="Chondrostei">Chondrostei</a> <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Atlantic_sturgeon.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Atlantic_sturgeon.jpg/50px-Atlantic_sturgeon.jpg" decoding="async" width="50" height="12" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Atlantic_sturgeon.jpg/75px-Atlantic_sturgeon.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d2/Atlantic_sturgeon.jpg/100px-Atlantic_sturgeon.jpg 2x" data-file-width="480" data-file-height="116" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Neopterygii" title="Neopterygii">Neopterygii</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Holostei" title="Holostei">Holostei</a> <span typeof="mw:File"><a href="/wiki/File:Alligator_gar_fish_(white_background).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Alligator_gar_fish_%28white_background%29.jpg/50px-Alligator_gar_fish_%28white_background%29.jpg" decoding="async" width="50" height="12" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Alligator_gar_fish_%28white_background%29.jpg/75px-Alligator_gar_fish_%28white_background%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/eb/Alligator_gar_fish_%28white_background%29.jpg/100px-Alligator_gar_fish_%28white_background%29.jpg 2x" data-file-width="1043" data-file-height="251" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Teleostei" class="mw-redirect" title="Teleostei">Teleostei</a> <span typeof="mw:File"><a href="/wiki/File:Common_carp_(white_background).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Common_carp_%28white_background%29.jpg/45px-Common_carp_%28white_background%29.jpg" decoding="async" width="45" height="19" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Common_carp_%28white_background%29.jpg/68px-Common_carp_%28white_background%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Common_carp_%28white_background%29.jpg/90px-Common_carp_%28white_background%29.jpg 2x" data-file-width="879" data-file-height="379" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Sarcopterygii" title="Sarcopterygii">Sarcopterygii</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Actinistia" class="mw-redirect" title="Actinistia">Actinistia</a> (coelacanths) <span typeof="mw:File"><a href="/wiki/File:Coelacanth_flipped.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/26/Coelacanth_flipped.png/45px-Coelacanth_flipped.png" decoding="async" width="45" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/26/Coelacanth_flipped.png/68px-Coelacanth_flipped.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/26/Coelacanth_flipped.png/90px-Coelacanth_flipped.png 2x" data-file-width="623" data-file-height="228" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Rhipidistia" title="Rhipidistia">Rhipidistia</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Dipnoi" class="mw-redirect" title="Dipnoi">Dipnoi</a> (lungfish) <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Chinle_fish_Arganodus_cropped_cropped.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/36/Chinle_fish_Arganodus_cropped_cropped.png/60px-Chinle_fish_Arganodus_cropped_cropped.png" decoding="async" width="50" height="12" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/36/Chinle_fish_Arganodus_cropped_cropped.png/120px-Chinle_fish_Arganodus_cropped_cropped.png 1.5x" data-file-width="1412" data-file-height="342" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Tetrapoda" class="mw-redirect" title="Tetrapoda">Tetrapoda</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Amphibia" class="mw-redirect" title="Amphibia">Amphibia</a> <span typeof="mw:File"><a href="/wiki/File:Salamandra_salamandra_(white_background).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Salamandra_salamandra_%28white_background%29.jpg/60px-Salamandra_salamandra_%28white_background%29.jpg" decoding="async" width="50" height="13" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cd/Salamandra_salamandra_%28white_background%29.jpg/120px-Salamandra_salamandra_%28white_background%29.jpg 1.5x" data-file-width="1038" data-file-height="277" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"><a href="/wiki/Amniota" class="mw-redirect" title="Amniota">Amniota</a> </td> <td rowspan="2" class="clade-leaf"> <div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1261294616" /> <table class="clade"> <tbody><tr> <td class="clade-label first"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Sauropsida" title="Sauropsida">Sauropsida</a> <span style="display: inline-block; transform: scaleX(-1);"><span typeof="mw:File"><a href="/wiki/File:Deinosuchus_riograndensis.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Deinosuchus_riograndensis.png/50px-Deinosuchus_riograndensis.png" decoding="async" width="50" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Deinosuchus_riograndensis.png/75px-Deinosuchus_riograndensis.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e6/Deinosuchus_riograndensis.png/100px-Deinosuchus_riograndensis.png 2x" data-file-width="999" data-file-height="300" /></a></span></span> </p> </td></tr> <tr> <td class="clade-slabel"> </td></tr> <tr> <td class="clade-label"> </td> <td rowspan="2" class="clade-leaf"> <p><a href="/wiki/Synapsida" title="Synapsida">Synapsida</a> <span typeof="mw:File"><a href="/wiki/File:Ruskea_rotta.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Ruskea_rotta.png/40px-Ruskea_rotta.png" decoding="async" width="40" height="20" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Ruskea_rotta.png/60px-Ruskea_rotta.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/df/Ruskea_rotta.png/80px-Ruskea_rotta.png 2x" data-file-width="222" data-file-height="110" /></a></span> </p> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> </td></tr> <tr> <td class="clade-slabel last"> </td></tr></tbody></table></div> <div style="clear:both;" class=""></div> <div class="mw-heading mw-heading2"><h2 id="Closest_nonchordate_relatives">Closest nonchordate relatives</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=11" title="Edit section: Closest nonchordate relatives"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Enteropneusta.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Enteropneusta.png/220px-Enteropneusta.png" decoding="async" width="220" height="275" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Enteropneusta.png/330px-Enteropneusta.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Enteropneusta.png/440px-Enteropneusta.png 2x" data-file-width="714" data-file-height="893" /></a><figcaption>Acorn worms or Enteropneusts are example of hemichordates.</figcaption></figure> <p>The closest relatives of the chordates are believed to be the <a href="/wiki/Hemichordate" title="Hemichordate">hemichordates</a> and <a href="/wiki/Echinodermata" class="mw-redirect" title="Echinodermata">Echinodermata</a>, which together form the <a href="/wiki/Ambulacraria" title="Ambulacraria">Ambulacraria</a>. The Chordata and Ambulacraria together form the superphylum <a href="/wiki/Deuterostomia" class="mw-redirect" title="Deuterostomia">Deuterostomia</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Hemichordates">Hemichordates</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=12" title="Edit section: Hemichordates"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Hemichordate" title="Hemichordate">Hemichordate</a></div> <p><a href="/wiki/Hemichordate" title="Hemichordate">Hemichordates</a> ("half chordates") have some features similar to those of chordates: branchial openings that open into the <a href="/wiki/Pharynx" title="Pharynx">pharynx</a> and look rather like gill slits; stomochords, similar in composition to <a href="/wiki/Notochord" title="Notochord">notochords</a>, but running in a circle round the "collar", which is ahead of the mouth; and a <a href="/wiki/Dorsa" class="mw-redirect" title="Dorsa">dorsal</a> nerve cord—but also a smaller <a href="/wiki/Ventral" class="mw-redirect" title="Ventral">ventral</a> nerve cord. </p><p>There are two living groups of hemichordates. The solitary <a href="/wiki/Enteropneust" class="mw-redirect" title="Enteropneust">enteropneusts</a>, commonly known as "acorn worms", have long <a href="/wiki/Proboscis" title="Proboscis">proboscises</a> and worm-like bodies with up to 200 branchial slits, are up to 2.5 metres (8.2 ft) long, and burrow though <a href="/wiki/Seafloor_sediment" class="mw-redirect" title="Seafloor sediment">seafloor sediments</a>. <a href="/wiki/Pterobranch" class="mw-redirect" title="Pterobranch">Pterobranchs</a> are <a href="/wiki/Colony_(biology)" title="Colony (biology)">colonial</a> animals, often less than 1 millimetre (0.039 in) long individually, whose dwellings are interconnected. Each <a href="/wiki/Filter_feeding" class="mw-redirect" title="Filter feeding">filter feeds</a> by means of a pair of branched tentacles, and has a short, shield-shaped proboscis. The extinct <a href="/wiki/Graptolite" title="Graptolite">graptolites</a>, colonial animals whose fossils look like tiny <a href="/wiki/Hacksaw" title="Hacksaw">hacksaw</a> blades, lived in tubes similar to those of pterobranchs.<sup id="cite_ref-66" class="reference"><a href="#cite_note-66"><span class="cite-bracket">[</span>65<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Echinoderms">Echinoderms</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=13" title="Edit section: Echinoderms"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Estrella_de_mar_de_espinas_rojas_(Protoreaster_linckii),_Zanz%C3%ADbar,_Tanzania,_2024-06-01,_DD_06.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Estrella_de_mar_de_espinas_rojas_%28Protoreaster_linckii%29%2C_Zanz%C3%ADbar%2C_Tanzania%2C_2024-06-01%2C_DD_06.jpg/203px-Estrella_de_mar_de_espinas_rojas_%28Protoreaster_linckii%29%2C_Zanz%C3%ADbar%2C_Tanzania%2C_2024-06-01%2C_DD_06.jpg" decoding="async" width="203" height="203" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Estrella_de_mar_de_espinas_rojas_%28Protoreaster_linckii%29%2C_Zanz%C3%ADbar%2C_Tanzania%2C_2024-06-01%2C_DD_06.jpg/305px-Estrella_de_mar_de_espinas_rojas_%28Protoreaster_linckii%29%2C_Zanz%C3%ADbar%2C_Tanzania%2C_2024-06-01%2C_DD_06.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Estrella_de_mar_de_espinas_rojas_%28Protoreaster_linckii%29%2C_Zanz%C3%ADbar%2C_Tanzania%2C_2024-06-01%2C_DD_06.jpg/406px-Estrella_de_mar_de_espinas_rojas_%28Protoreaster_linckii%29%2C_Zanz%C3%ADbar%2C_Tanzania%2C_2024-06-01%2C_DD_06.jpg 2x" data-file-width="4861" data-file-height="4861" /></a><figcaption>A red knob sea star, <i><a href="/wiki/Protoreaster_linckii" class="mw-redirect" title="Protoreaster linckii">Protoreaster linckii</a></i> is an example of an <a href="/wiki/Asterozoa" title="Asterozoa">asterozoan</a> <a href="/wiki/Echinoderm" title="Echinoderm">echinoderm</a>.</figcaption></figure> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951" /><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Echinoderm" title="Echinoderm">Echinoderm</a></div> <p><a href="/wiki/Echinoderm" title="Echinoderm">Echinoderms</a> differ from chordates and their other relatives in three conspicuous ways: they possess <a href="/wiki/Bilateral_symmetry" class="mw-redirect" title="Bilateral symmetry">bilateral symmetry</a> only as larvae – in adulthood they have <a href="/wiki/Radial_symmetry" class="mw-redirect" title="Radial symmetry">radial symmetry</a>, meaning that their body pattern is shaped like a wheel; they have <a href="/wiki/Tube_feet" title="Tube feet">tube feet</a>; and their bodies are supported by <a href="/wiki/Dermal" class="mw-redirect" title="Dermal">dermal</a> <a href="/wiki/Skeleton" title="Skeleton">skeletons</a> made of <a href="/wiki/Calcite" title="Calcite">calcite</a>, a material not used by chordates. Their hard, calcified shells keep their bodies well protected from the environment, and these skeletons enclose their bodies, but are also covered by thin skins. The feet are powered by another unique feature of echinoderms, a <a href="/wiki/Water_vascular_system" title="Water vascular system">water vascular system</a> of canals that also functions as a "lung" and surrounded by muscles that act as pumps. <a href="/wiki/Crinoid" title="Crinoid">Crinoids</a> are typically <a href="/wiki/Sessility_(motility)" title="Sessility (motility)">sessile</a> and look rather like flowers (hence the <a href="/wiki/Common_name" title="Common name">common name</a> "<a href="/wiki/Sea_lilies" class="mw-redirect" title="Sea lilies">sea lilies</a>"), and use their feather-like arms to filter food particles out of the water; most live anchored to rocks, but a few species can move very slowly. Other echinoderms are mobile and take a variety of body shapes, for example <a href="/wiki/Starfish" title="Starfish">starfish</a> and <a href="/wiki/Brittle_star" title="Brittle star">brittle stars</a>, <a href="/wiki/Sea_urchin" title="Sea urchin">sea urchins</a> and <a href="/wiki/Sea_cucumber" title="Sea cucumber">sea cucumbers</a>.<sup id="cite_ref-CowenHistLifeEd3P412_67-0" class="reference"><a href="#cite_note-CowenHistLifeEd3P412-67"><span class="cite-bracket">[</span>66<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=14" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Chordate_genomics" title="Chordate genomics">Chordate genomics</a> – Study of the evolution of the chordate clade</li> <li><a href="/wiki/List_of_chordate_orders" title="List of chordate orders">List of chordate orders</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=15" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-lower-alpha"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text">The classification below follows Benton 2004, and uses a synthesis of rank-based Linnaean taxonomy and also reflects evolutionary relationships. Benton included the superclass Tetrapoda in the subclass Sarcopterygii in order to reflect the direct descent of tetrapods from lobe-finned fish, despite the former being assigned a higher taxonomic rank</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=16" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626" /><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFYangLiZhuCondon2018" class="citation journal cs1">Yang, Chuan; 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title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=BMC+Biology&rft.atitle=A+phylogenomic+framework+and+timescale+for+comparative+studies+of+tunicates&rft.volume=16&rft.issue=1&rft.pages=39&rft.date=2018-04&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC5899321%23id-name%3DPMC&rft_id=info%3Apmid%2F29653534&rft_id=info%3Adoi%2F10.1186%2Fs12915-018-0499-2&rft.aulast=Delsuc&rft.aufirst=F&rft.au=Philippe%2C+H&rft.au=Tsagkogeorga%2C+G&rft.au=Simion%2C+P&rft.au=Tilak%2C+MK&rft.au=Turon%2C+X&rft.au=L%C3%B3pez-Legentil%2C+S&rft.au=Piette%2C+J&rft.au=Lemaire%2C+P&rft.au=Douzery%2C+EJ&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC5899321&rfr_id=info%3Asid%2Fen.wikipedia.org%3AChordate" class="Z3988"></span></span> </li> <li id="cite_note-64"><span class="mw-cite-backlink"><b><a href="#cite_ref-64">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" 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title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Placodermi+%28Armoured+Fishes%29&rft.btitle=ELS&rft.pages=%3Cspan+class%3D%22nowrap%22%3E1-%3C%2Fspan%3E7&rft.pub=John+Wiley+%26+Sons%2C+Ltd&rft.date=2015-02-16&rft_id=info%3Adoi%2F10.1002%2F9780470015902.a0001533.pub2&rft.isbn=978-0-470-01590-2&rft.aulast=Goujet&rft.aufirst=Daniel+F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AChordate" class="Z3988"></span></span> </li> <li id="cite_note-65"><span class="mw-cite-backlink"><b><a href="#cite_ref-65">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFMiyashitaCoatesFarrarLarson2019" class="citation journal cs1">Miyashita, Tetsuto; Coates, Michael I.; Farrar, Robert; Larson, Peter; Manning, Phillip L.; Wogelius, Roy A.; et al. (2019). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369785">"Hagfish from the Cretaceous Tethys Sea and a reconciliation of the morphological–molecular conflict in early vertebrate phylogeny"</a>. <i>Proceedings of the National Academy of Sciences of the United States of America</i>. <b>116</b> (6): <span class="nowrap">2146–</span>2151. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2019PNAS..116.2146M">2019PNAS..116.2146M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1073%2Fpnas.1814794116">10.1073/pnas.1814794116</a></span>. <a href="/wiki/PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6369785">6369785</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/30670644">30670644</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Proceedings+of+the+National+Academy+of+Sciences+of+the+United+States+of+America&rft.atitle=Hagfish+from+the+Cretaceous+Tethys+Sea+and+a+reconciliation+of+the+morphological%E2%80%93molecular+conflict+in+early+vertebrate+phylogeny&rft.volume=116&rft.issue=6&rft.pages=%3Cspan+class%3D%22nowrap%22%3E2146-%3C%2Fspan%3E2151&rft.date=2019&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC6369785%23id-name%3DPMC&rft_id=info%3Apmid%2F30670644&rft_id=info%3Adoi%2F10.1073%2Fpnas.1814794116&rft_id=info%3Abibcode%2F2019PNAS..116.2146M&rft.aulast=Miyashita&rft.aufirst=Tetsuto&rft.au=Coates%2C+Michael+I.&rft.au=Farrar%2C+Robert&rft.au=Larson%2C+Peter&rft.au=Manning%2C+Phillip+L.&rft.au=Wogelius%2C+Roy+A.&rft.au=Edwards%2C+Nicholas+P.&rft.au=Ann%C3%A9%2C+Jennifer&rft.au=Bergmann%2C+Uwe&rft.au=Palmer%2C+A.+Richard&rft.au=Currie%2C+Philip+J.&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC6369785&rfr_id=info%3Asid%2Fen.wikipedia.org%3AChordate" class="Z3988"></span></span> </li> <li id="cite_note-66"><span class="mw-cite-backlink"><b><a href="#cite_ref-66">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20190201080336/http://www.ucmp.berkeley.edu/chordata/hemichordata.html">"Introduction to the Hemichordata"</a>. University of California Museum of Paleontology. Archived from <a rel="nofollow" class="external text" href="http://www.ucmp.berkeley.edu/chordata/hemichordata.html">the original</a> on 1 February 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">22 September</span> 2008</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Introduction+to+the+Hemichordata&rft.pub=University+of+California+Museum+of+Paleontology&rft_id=http%3A%2F%2Fwww.ucmp.berkeley.edu%2Fchordata%2Fhemichordata.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AChordate" class="Z3988"></span></span> </li> <li id="cite_note-CowenHistLifeEd3P412-67"><span class="mw-cite-backlink"><b><a href="#cite_ref-CowenHistLifeEd3P412_67-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFCowen,_R.2000" class="citation book cs1">Cowen, R. (2000). <i>History of Life</i> (3rd ed.). Blackwell Science. p. 412. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-632-04444-3" title="Special:BookSources/978-0-632-04444-3"><bdi>978-0-632-04444-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=History+of+Life&rft.pages=412&rft.edition=3rd&rft.pub=Blackwell+Science&rft.date=2000&rft.isbn=978-0-632-04444-3&rft.au=Cowen%2C+R.&rfr_id=info%3Asid%2Fen.wikipedia.org%3AChordate" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Chordate&action=edit&section=17" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1237033735">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media 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srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikispecies-logo.svg/60px-Wikispecies-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikispecies-logo.svg/120px-Wikispecies-logo.svg.png 2x" data-file-width="941" data-file-height="1103" /></a></span></div> <div class="side-box-text plainlist"><a href="/wiki/Wikispecies" title="Wikispecies">Wikispecies</a> has information related to <i><b><a href="https://species.wikimedia.org/wiki/Chordata" class="extiw" title="wikispecies:Chordata">Chordata</a></b></i>.</div></div> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1235681985" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1237033735" /><div class="side-box side-box-right plainlinks sistersitebox"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409" /> <div class="side-box-flex"> <div class="side-box-image"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Wikibooks-logo-en-noslogan.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikibooks-logo-en-noslogan.svg/40px-Wikibooks-logo-en-noslogan.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikibooks-logo-en-noslogan.svg/60px-Wikibooks-logo-en-noslogan.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/df/Wikibooks-logo-en-noslogan.svg/120px-Wikibooks-logo-en-noslogan.svg.png 2x" data-file-width="400" data-file-height="400" /></a></span></div> <div class="side-box-text plainlist">The Wikibook <i><a href="https://en.wikibooks.org/wiki/Dichotomous_Key" class="extiw" title="wikibooks:Dichotomous Key">Dichotomous Key</a></i> has a page on the topic of: <i><b><a href="https://en.wikibooks.org/wiki/Dichotomous_Key/Chordata" class="extiw" title="wikibooks:Dichotomous Key/Chordata">Chordata</a></b></i></div></div> </div> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20230000000000/http://www.eol.org/pages/694">"<i>Chordate</i>"</a>. <i>The <a href="/wiki/Encyclopedia_of_Life" title="Encyclopedia of Life">Encyclopedia of Life</a></i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=The+Encyclopedia+of+Life&rft.atitle=%3Ci%3EChordate%3C%2Fi%3E&rft_id=https%3A%2F%2Fweb.archive.org%2Fweb%2F20230000000000%2Fhttp%3A%2F%2Fwww.eol.org%2Fpages%2F694&rfr_id=info%3Asid%2Fen.wikipedia.org%3AChordate" class="Z3988"></span> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q10915#P830" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110425151037/http://www.globaltwitcher.com/taxa_class.asp?phylaid=1">Chordate on GlobalTwitcher.com</a></li> <li><a rel="nofollow" class="external text" href="http://tolweb.org/Chordata/2499">Chordate node at Tree Of Life</a></li> <li><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=7711">Chordate node at NCBI Taxonomy</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist 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aria-labelledby="Extant_animal_phyla1042" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2" style="background:rgb(235,235,210);background:rgb(211,211,164)"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Animalia" title="Template:Animalia"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Animalia" title="Template talk:Animalia"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Animalia" title="Special:EditPage/Template:Animalia"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Extant_animal_phyla1042" style="font-size:114%;margin:0 4em">Extant <a href="/wiki/Animal" title="Animal">animal</a> <a href="/wiki/Phylum" title="Phylum">phyla</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2" style="background:rgb(235,235,210)"><div><div class="hlist"> <dl><dt><span class="nobold"><a href="/wiki/Domain_(biology)" title="Domain (biology)">Domain</a></span></dt> <dd><a href="/wiki/Template:Archaea_classification" title="Template:Archaea classification">Archaea</a></dd> <dd><a href="/wiki/Template:Bacteria_classification" title="Template:Bacteria classification">Bacteria</a></dd> <dd><a href="/wiki/Template:Eukaryota" title="Template:Eukaryota">Eukaryota</a></dd> <dt><span class="nobold">(major groups</span></dt> <dd>"<a href="/wiki/Template:Excavata" title="Template:Excavata">Excavata</a>"</dd> <dd><a href="/wiki/Diaphoretickes" title="Diaphoretickes">Diaphoretickes</a> <dl><dd><a href="/wiki/Template:Hacrobia" title="Template:Hacrobia">Hacrobia</a> <dl><dd><a href="/wiki/Template:Cryptista" title="Template:Cryptista">Cryptista</a></dd></dl></dd> <dd><a href="/wiki/Template:Rhizaria" title="Template:Rhizaria">Rhizaria</a></dd> <dd><a href="/wiki/Template:Alveolata" title="Template:Alveolata">Alveolata</a></dd> <dd><a href="/wiki/Template:Stramenopile" title="Template:Stramenopile">Stramenopiles</a></dd> <dd><a href="/wiki/Template:Plant_classification" title="Template:Plant classification">Plants</a></dd></dl></dd> <dd><a href="/wiki/Amorphea" title="Amorphea">Amorphea</a> <dl><dd><a href="/wiki/Template:Amoebozoa" title="Template:Amoebozoa">Amoebozoa</a></dd> <dd><a href="/wiki/Template:Opisthokont_protists" class="mw-redirect" title="Template:Opisthokont protists">Opisthokonta</a> <dl><dd><a href="/wiki/Template:Animalia" title="Template:Animalia">Animals</a></dd> <dd><a href="/wiki/Template:Fungi_classification" title="Template:Fungi classification">Fungi</a></dd> <dd><a href="/wiki/Template:Mesomycetozoea" title="Template:Mesomycetozoea">Mesomycetozoea</a>)</dd></dl></dd></dl></dd></dl> </div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Animalia436" scope="row" class="navbox-group" style="background:rgb(245,245,232);width:1%;background:rgb(235,235,210)"><span style="margin: -25px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Animal" title="Animal">Animalia</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Sponge" title="Sponge"><b>Porifera (sponges)</b></a></li> <li><a href="/wiki/Ctenophora" title="Ctenophora">Ctenophora (comb jellies)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/ParaHoxozoa" title="ParaHoxozoa">ParaHoxozoa</a><br />(<a href="/wiki/Planulozoa" title="Planulozoa">Planulozoa</a>)</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Placozoa" title="Placozoa">Placozoa (<i>Trichoplax</i> and relatives)</a></li> <li><a href="/wiki/Cnidaria" title="Cnidaria"><b>Cnidaria (jellyfish and relatives)</b></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Bilateria" title="Bilateria">Bilateria</a> (Triploblasts)</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>(see below↓)</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="background:rgb(245,245,232)"><div> <dl><dt><span class="nobold">The <a href="/wiki/Phylogenetic_tree" title="Phylogenetic tree">phylogeny</a> of the animal root <a href="/wiki/Animal#Internal_phylogeny" title="Animal">is disputed</a>; see also</span></dt> <dd><a href="/wiki/Eumetazoa" title="Eumetazoa">Eumetazoa</a></dd> <dd><a href="/wiki/Benthozoa" title="Benthozoa">Benthozoa</a></dd></dl> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible uncollapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2" style="background:rgb(235,235,210)"><div id="Bilateria1042" style="font-size:114%;margin:0 4em"><a href="/wiki/Bilateria" title="Bilateria">Bilateria</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Bilateria485" scope="row" class="navbox-group" style="background:rgb(245,245,232);width:1%;background:rgb(235,235,210)"><span style="margin: -24px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Bilateria" title="Bilateria">Bilateria</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Xenacoelomorpha" title="Xenacoelomorpha">Xenacoelomorpha (acoels and relatives)</a></li> <li><b><a class="mw-selflink selflink">Chordata (chordates)</a></b></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Ambulacraria" title="Ambulacraria">Ambulacraria</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Echinoderm" title="Echinoderm"><b>Echinodermata (starfish and relatives)</b></a></li> <li><a href="/wiki/Hemichordate" title="Hemichordate">Hemichordata (acorn worms and relatives)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Protostomia240" scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><span style="margin: -35px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Protostome" title="Protostome">Protostomia</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><span style="margin: -30px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Ecdysozoa" title="Ecdysozoa">Ecdysozoa</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Scalidophora16" scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Scalidophora" title="Scalidophora">Scalidophora</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Kinorhyncha" title="Kinorhyncha">Kinorhyncha (mud dragons)</a></li> <li><a href="/wiki/Priapulida" title="Priapulida">Priapulida (penis worms)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)">N+L+P</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Nematoida13" scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Nematoida" title="Nematoida">Nematoida</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nematode" title="Nematode"><b>Nematoda (roundworms)</b></a></li> <li><a href="/wiki/Nematomorpha" title="Nematomorpha">Nematomorpha (horsehair worms)</a></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="L+P3" scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)">L+P</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Loricifera" title="Loricifera">Loricifera (corset animals)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Panarthropoda" title="Panarthropoda">Panarthropoda</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Onychophora" title="Onychophora">Onychophora (velvet worms)</a></li> <li><a href="/wiki/Arthropod" title="Arthropod"><b>Arthropoda (arthropods)</b></a></li> <li><a href="/wiki/Tardigrade" title="Tardigrade"><b>Tardigrada (waterbears)</b></a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><span style="margin: -20px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Spiralia" title="Spiralia">Spiralia</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Gnathifera36" scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Gnathifera_(Spiralia)" title="Gnathifera (Spiralia)">Gnathifera</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Chaetognatha" title="Chaetognatha">Chaetognatha (arrow worms)</a></li> <li><a href="/wiki/Gnathostomulid" title="Gnathostomulid">Gnathostomulida (jaw worms)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)">M+S</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Limnognathia" title="Limnognathia">Micrognathozoa <i>(Limnognathia)</i></a></li> <li><a href="/wiki/Syndermata" title="Syndermata">Syndermata</a> <ul><li><b><a href="/wiki/Rotifer" title="Rotifer">Rotifera (wheel animals)</a></b></li> <li><b><a href="/wiki/Acanthocephala" title="Acanthocephala">Acanthocephala (thorny-headed worms)</a></b></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><span style="margin: -41px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Platytrochozoa" title="Platytrochozoa">Platytrochozoa</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="R+M3" scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)">R+M</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Rouphozoa" class="mw-redirect" title="Rouphozoa">Rouphozoa</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Flatworm" title="Flatworm"><b>Platyhelminthes (flatworms)</b></a></li> <li><a href="/wiki/Gastrotrich" title="Gastrotrich">Gastrotricha (hairybacks)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Mesozoa" title="Mesozoa">Mesozoa</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Orthonectida" title="Orthonectida">Orthonectida</a></li> <li><a href="/wiki/Dicyemida" title="Dicyemida">Dicyemida or Rhombozoa</a></li> <li><a href="/wiki/Salinella" title="Salinella">Monoblastozoa (<i>Salinella</i>)</a>†</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><span style="margin: -44px; display: inline-block; -webkit-transform: rotate(270deg); -moz-transform: rotate(270deg); -ms-transform: rotate(270deg); -o-transform: rotate(270deg); transform: rotate(270deg);"><a href="/wiki/Lophotrochozoa" title="Lophotrochozoa">Lophotrochozoa</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Symbion" title="Symbion">Cycliophora (<i>Symbion</i>)</a></li> <li><a href="/wiki/Annelid" title="Annelid"><b>Annelida (segmented worms)</b></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)">M+K</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Mollusca" title="Mollusca"><b>Mollusca (molluscs)</b></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Kryptotrochozoa" title="Kryptotrochozoa">Kryptotrochozoa</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nemertea" title="Nemertea"><b>Nemertea (ribbon worms)</b></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Lophophorata" title="Lophophorata">Lophophorata</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Bryozoa" title="Bryozoa">Bryozoa s.l.</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Entoprocta" title="Entoprocta">Entoprocta or Kamptozoa</a></li> <li><a href="/wiki/Bryozoa" title="Bryozoa"><b>Ectoprocta (moss animals)</b></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;background:rgb(235,235,210)"><a href="/wiki/Brachiozoa" title="Brachiozoa">Brachiozoa</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Brachiopod" title="Brachiopod">Brachiopoda (lamp shells)</a></li> <li><a href="/wiki/Phoronid" title="Phoronid">Phoronida (horseshoe worms)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="background:rgb(245,245,232)"><div> <dl><dt><span class="nobold">The <a href="/wiki/Phylogenetic_tree" title="Phylogenetic tree">phylogeny</a> of Bilateria <a href="/wiki/Bilateria#Phylogeny" title="Bilateria">is disputed</a>; see also</span></dt> <dd><a href="/wiki/Nephrozoa" title="Nephrozoa">Nephrozoa</a></dd> <dd><a href="/wiki/Deuterostome" title="Deuterostome">Deuterostomia</a></dd> <dd><a href="/wiki/Xenambulacraria" title="Xenambulacraria">Xenambulacraria</a></dd> <dd><a href="/wiki/Centroneuralia" title="Centroneuralia">Centroneuralia</a></dd></dl> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"><hr /></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Major_groupswithin_phyla29" scope="row" class="navbox-group" style="width:1%;background-color: #f0f0f0;">Major groups<br />within phyla</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><b><a href="/wiki/Sponge" title="Sponge">Sponges</a></b> <ul><li><a href="/wiki/Demosponge" title="Demosponge">Demosponges</a></li> <li><a href="/wiki/Hexactinellid" title="Hexactinellid">Glass sponges</a></li> <li><a href="/wiki/Calcareous_sponge" title="Calcareous sponge">Calcareous sponges</a></li></ul></li> <li><b><a href="/wiki/Cnidaria" title="Cnidaria">Cnidarians</a></b> <ul><li><a href="/wiki/Anthozoa" title="Anthozoa">Anthozoans inc. corals</a></li> <li><a href="/wiki/Medusozoa" title="Medusozoa">Medusozoans inc. jellyfish</a></li> <li><a href="/wiki/Myxozoa" title="Myxozoa">Myxozoans</a></li></ul></li> <li><b><a class="mw-selflink selflink">Chordates</a></b> <ul><li><a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">Lancelets</a></li> <li><a href="/wiki/Tunicate" title="Tunicate">Tunicates</a></li> <li><a href="/wiki/Vertebrate" title="Vertebrate">Vertebrates</a></li></ul></li> <li><b><a href="/wiki/Echinoderm" title="Echinoderm">Echinoderms</a></b> <ul><li><a href="/wiki/Crinozoa" title="Crinozoa">Sea lilies</a></li> <li><a href="/wiki/Asterozoa" title="Asterozoa">Asterozoans inc. starfish</a></li> <li><a href="/wiki/Echinozoa" title="Echinozoa">Echinozoans inc. sea urchins</a></li></ul></li> <li><b><a href="/wiki/Hemichordate" title="Hemichordate">Hemichordates</a></b> <ul><li><a href="/wiki/Acorn_worm" title="Acorn worm">Acorn worms</a></li> <li><a href="/wiki/Pterobranchia" title="Pterobranchia">Pterobranchs</a></li></ul></li> <li><b><a href="/wiki/Nematode" title="Nematode">Nematodes</a></b> <ul><li><a href="/wiki/Chromadorea" title="Chromadorea">Chromadorea</a></li> <li><a href="/wiki/Enoplea" title="Enoplea">Enoplea</a></li> <li><a href="/wiki/Secernentea" title="Secernentea">Secernentea</a></li></ul></li> <li><b><a href="/wiki/Arthropod" title="Arthropod">Arthropods</a></b> <ul><li><a href="/wiki/Chelicerata" title="Chelicerata">Chelicerates inc. arachnids</a></li> <li><a href="/wiki/Myriapoda" title="Myriapoda">Myriapods</a></li> <li><a href="/wiki/Crustacean" title="Crustacean">Crustaceans</a></li> <li><a href="/wiki/Hexapoda" title="Hexapoda">Hexapods inc. insects</a></li></ul></li> <li><b><a href="/wiki/Flatworm" title="Flatworm">Platyhelminths</a></b> <ul><li><a href="/wiki/Turbellaria" title="Turbellaria">Turbellaria</a></li> <li><a href="/wiki/Trematoda" title="Trematoda">Trematoda</a></li> <li><a href="/wiki/Monogenea" title="Monogenea">Monogenea</a></li> <li><a href="/wiki/Cestoda" title="Cestoda">Cestoda</a></li></ul></li> <li><b><a href="/wiki/Bryozoa" title="Bryozoa">Ectoproctans</a></b> <ul><li><a href="/wiki/Phylactolaemata" title="Phylactolaemata">Phylactolaemata</a></li> <li><a href="/wiki/Stenolaemata" title="Stenolaemata">Stenolaemata</a></li> <li><a href="/wiki/Gymnolaemata" title="Gymnolaemata">Gymnolaemata</a></li></ul></li> <li><b><a href="/wiki/Annelid" title="Annelid">Annelids</a></b> <ul><li><a href="/wiki/Polychaete" title="Polychaete">Polychaetes</a></li> <li><a href="/wiki/Clitellata" title="Clitellata">Clitellata</a></li> <li><a href="/wiki/Sipuncula" title="Sipuncula">Sipuncula</a></li></ul></li> <li><b><a href="/wiki/Mollusca" title="Mollusca">Molluscs</a></b> <ul><li><a href="/wiki/Gastropoda" title="Gastropoda">Gastropods</a></li> <li><a href="/wiki/Cephalopod" title="Cephalopod">Cephalopods</a></li> <li><a href="/wiki/Bivalvia" title="Bivalvia">Bivalves</a></li> <li><a href="/wiki/Chiton" title="Chiton">Chitons</a></li> <li><a href="/wiki/Tusk_shell" title="Tusk shell">Tusk shells</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="background:rgb(235,235,210)"><div> <dl><dd>Phyla with ≥1000 extant species <b>bolded</b></dd> <dd>Potentially <a href="/wiki/Dubious_species" class="mw-redirect" title="Dubious species">dubious phyla</a> †</dd></dl> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Extant_chordate_classes597" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Chordata" title="Template:Chordata"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Chordata" title="Template talk:Chordata"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Chordata" title="Special:EditPage/Template:Chordata"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Extant_chordate_classes597" style="font-size:114%;margin:0 4em">Extant <a class="mw-selflink selflink">chordate</a> classes</div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li>Kingdom <a href="/wiki/Animal" title="Animal">Animalia</a></li> <li>Clade <a href="/wiki/Bilateria" title="Bilateria">Bilateria</a></li> <li>Superphylum <a href="/wiki/Deuterostome" title="Deuterostome">Deuterostomia</a></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Cephalochordata73" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Cephalochordate" class="mw-redirect" title="Cephalochordate">Cephalochordata</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Lancelet" title="Lancelet">Leptocardii (lancelets)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.0em;"><span style="margin:-29px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Olfactores" title="Olfactores">Olfactores</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.2em;"><a href="/wiki/Tunicate" title="Tunicate">Tunicata<br /><span style="font-weight:normal; font-style:normal">(Urochordata)</span></a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Larvacean" title="Larvacean">Appendicularia (larvaceans)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Acopa</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Stolidobranchia" title="Stolidobranchia">Stolidobranchia</a>¹</li> <li><a href="/wiki/Thaliacea" title="Thaliacea">Thaliacea (pyrosomes, salps, doliolids)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Enterogona" class="mw-redirect" title="Enterogona">Enterogona</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Phlebobranchia" title="Phlebobranchia">Phlebobranchia</a>¹</li> <li><a href="/wiki/Aplousobranchia" title="Aplousobranchia">Aplousobranchia</a>¹</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.2em;"><span style="margin:-29px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Vertebrate" title="Vertebrate">Vertebrata</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Cyclostomata87" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Cyclostomata" class="mw-redirect" title="Cyclostomata">Cyclostomata</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hagfish" title="Hagfish">Myxini (hagfish)</a></li> <li><a href="/wiki/Hyperoartia" class="mw-redirect" title="Hyperoartia">Hyperoartia (lampreys)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.2em;"><span style="margin:-37px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Gnathostomata" title="Gnathostomata">Gnathostomata<br /><span style="font-weight:normal; font-style:normal">(jawed vertebrates)</span></a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Chondrichthyes" title="Chondrichthyes">Chondrichthyes (cartilaginous fish: sharks, rays, chimaeras)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.2em;text-align:left;"><span style="margin:-32px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Euteleostomi" title="Euteleostomi">Euteleostomi<br /><span style="font-weight:normal; font-style:normal">(bony vertebrates)</span></a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Actinopterygii" title="Actinopterygii">Actinopterygii (ray-finned fish)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.2em;"><span style="margin:-32px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Sarcopterygii" title="Sarcopterygii">Sarcopterygii<br /><span style="font-weight:normal; font-style:normal">(lobe-finned fish)</span></a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Actinistia" class="mw-redirect" title="Actinistia">Actinistia (coelacanths)</a>²</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.0em;"><span style="margin:-29px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Rhipidistia" title="Rhipidistia">Rhipidistia</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Lungfish" title="Lungfish">Dipnoi (lungfish)</a>²</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.0em;"><span style="margin:-29px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Tetrapod" title="Tetrapod">Tetrapoda</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Lissamphibia" title="Lissamphibia">Lissamphibia (modern amphibians: frogs, salamanders, caecilians)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.0em;"><span style="margin:-25px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Amniote" title="Amniote">Amniota</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Mammal" title="Mammal">Mammalia (mammals)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;line-height:1.2em;"><span style="margin:-19px;display: inline-block;-webkit-transform: rotate(270deg);-moz-transform: rotate(270deg);-ms-transform: rotate(270deg);-o-transform: rotate(270deg);transform: rotate(270deg);"><a href="/wiki/Sauria" title="Sauria">Sauria</a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Lepidosauria" title="Lepidosauria">Lepidosauria</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Rhynchocephalia" title="Rhynchocephalia">Rhynchocephalia (tuatara)</a>³</li> <li><a href="/wiki/Squamata" title="Squamata">Squamata (scaled reptiles: snakes, lizards, worm lizards)</a>³</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Archelosauria" title="Archelosauria">Archelosauria</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Turtle" title="Turtle">Testudines (turtles)</a>³</li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Archosauria81" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Archosaur" title="Archosaur">Archosauria</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Crocodilia" title="Crocodilia">Crocodilia (crocodilians)</a>³</li> <li><a href="/wiki/Bird" title="Bird">Aves (birds)</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li>¹orders of class <i><a href="/wiki/Ascidiacea" title="Ascidiacea">Ascidiacea (sea squirts)</a></i></li> <li>²classes of clade <a href="/wiki/Sarcopterygii" title="Sarcopterygii">Sarcopterygii (lobe-finned fish and descendants)</a></li> <li>³orders of traditional class <i><a href="/wiki/Reptile" title="Reptile">Reptilia (reptiles)</a></i></li> <li><i>italics</i> denote paraphyletic groups</li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Extant_life_phyla/divisions_by_domain41" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231" /><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Life_on_Earth" title="Template:Life on Earth"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Life_on_Earth" title="Template talk:Life on Earth"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Life_on_Earth" title="Special:EditPage/Template:Life on Earth"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Extant_life_phyla/divisions_by_domain41" style="font-size:114%;margin:0 4em">Extant <a href="/wiki/Life" title="Life">life</a> phyla/divisions by domain</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Bacteria12" scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Bacteria" title="Bacteria">Bacteria</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acidobacteriota" title="Acidobacteriota">Acidobacteriota</a></li> <li><a href="/wiki/Actinomycetota" title="Actinomycetota">Actinomycetota</a></li> <li><a href="/wiki/Aquificota" title="Aquificota">Aquificota</a></li> <li><a href="/wiki/Armatimonadota" title="Armatimonadota">Armatimonadota</a></li> <li><a href="/wiki/Atribacterota" title="Atribacterota">Atribacterota</a></li> <li><a href="/wiki/Bacillota" title="Bacillota">Bacillota</a></li> <li><a href="/wiki/Bacteroidota" title="Bacteroidota">Bacteroidota</a></li> <li><a href="/wiki/Balneolota" class="mw-redirect" title="Balneolota">Balneolota</a></li> <li><a href="/wiki/Bdellovibrionota" title="Bdellovibrionota">Bdellovibrionota</a></li> <li><a href="/wiki/Caldisericota" class="mw-redirect" title="Caldisericota">Caldisericota</a></li> <li><a href="/wiki/Calditrichota" class="mw-redirect" title="Calditrichota">Calditrichota</a></li> <li><a href="/wiki/Campylobacterota" title="Campylobacterota">Campylobacterota</a></li> <li><a href="/wiki/Chlamydiota" title="Chlamydiota">Chlamydiota</a></li> <li><a href="/wiki/Green_sulfur_bacteria" title="Green sulfur bacteria">Chlorobiota</a></li> <li><a href="/wiki/Chloroflexota" title="Chloroflexota">Chloroflexota</a></li> <li><a href="/wiki/Chrysiogenota" class="mw-redirect" title="Chrysiogenota">Chrysiogenota</a></li> <li><a href="/wiki/Coprothermobacterota" title="Coprothermobacterota">Coprothermobacterota</a></li> <li><a href="/wiki/Cyanobacteriota" class="mw-redirect" title="Cyanobacteriota">Cyanobacteriota</a></li> <li><a href="/wiki/Deferribacteraceae" title="Deferribacteraceae">Deferribacterota</a></li> <li><a href="/wiki/Deinococcota" title="Deinococcota">Deinococcota</a></li> <li><a href="/wiki/Dictyoglomus_thermophilum" title="Dictyoglomus thermophilum">Dictyoglomota</a></li> <li><a href="/wiki/Elusimicrobiota" title="Elusimicrobiota">Elusimicrobiota</a></li> <li><a href="/wiki/Fibrobacterota" title="Fibrobacterota">Fibrobacterota</a></li> <li><a href="/wiki/Fusobacteriota" title="Fusobacteriota">Fusobacteriota</a></li> <li><a href="/wiki/Gemmatimonadota" title="Gemmatimonadota">Gemmatimonadota</a></li> <li><a href="/wiki/Ignavibacteriota" class="mw-redirect" title="Ignavibacteriota">Ignavibacteriota</a></li> <li><a href="/wiki/Kiritimatiellota" title="Kiritimatiellota">Kiritimatiellota</a></li> <li><a href="/wiki/Lentisphaerota" title="Lentisphaerota">Lentisphaerota</a></li> <li><a href="/wiki/Mycoplasmatota" title="Mycoplasmatota">Mycoplasmatota</a></li> <li><a href="/wiki/Myxococcota" title="Myxococcota">Myxococcota</a></li> <li><a href="/wiki/Nitrospinota" title="Nitrospinota">Nitrospinota</a></li> <li><a href="/wiki/Nitrospirota" title="Nitrospirota">Nitrospirota</a></li> <li><a href="/wiki/Planctomycetota" title="Planctomycetota">Planctomycetota</a></li> <li><a href="/wiki/Pseudomonadota" title="Pseudomonadota">Pseudomonadota</a></li> <li><a href="/wiki/Rhodothermota" class="mw-redirect" title="Rhodothermota">Rhodothermota</a></li> <li><a href="/wiki/Spirochaetota" class="mw-redirect" title="Spirochaetota">Spirochaetota</a></li> <li><a href="/wiki/Synergistota" title="Synergistota">Synergistota</a></li> <li><a href="/wiki/Thermodesulfobacteriota" title="Thermodesulfobacteriota">Thermodesulfobacteriota</a></li> <li><a href="/wiki/Thermomicrobiota" class="mw-redirect" title="Thermomicrobiota">Thermomicrobiota</a></li> <li><a href="/wiki/Thermotogota" class="mw-redirect" title="Thermotogota">Thermotogota</a></li> <li><a href="/wiki/Verrucomicrobiota" title="Verrucomicrobiota">Verrucomicrobiota</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Archaea11" scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Archaea" title="Archaea">Archaea</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li>"<a href="/wiki/Korarchaeota" title="Korarchaeota">Korarchaeota</a>"</li> <li><a href="/wiki/Methanobacteriota" title="Methanobacteriota">Methanobacteriota</a></li> <li>"<a href="/wiki/Nanobdellati" title="Nanobdellati"><i>Candidatus</i> Micrarchaeota</a>"</li> <li><a href="/wiki/Nanoarchaeota" title="Nanoarchaeota">Nanobdellati</a></li> <li><a href="/wiki/Nitrososphaerota" title="Nitrososphaerota">Nitrososphaerota</a></li> <li>"<a href="/wiki/Parvarchaeota" title="Parvarchaeota"><i>Candidatus</i> Parvarchaeota</a>"</li> <li><a href="/wiki/Thermoproteota" title="Thermoproteota">Thermoproteota</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em"><a href="/wiki/Eukaryote" title="Eukaryote">Eukaryote</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">"<a href="/wiki/Protist" title="Protist">Protist</a>"</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alveolata" class="mw-redirect" title="Alveolata">Alveolata</a></li> <li><a href="/wiki/Amoebozoa" title="Amoebozoa">Amoebozoa</a></li> <li><a href="/wiki/Apusomonadida" class="mw-redirect" title="Apusomonadida">Apusomonadida</a></li> <li><a href="/wiki/Breviatea" title="Breviatea">Breviatea</a></li> <li><a href="/wiki/CRuMs" title="CRuMs">CRuMs</a></li> <li><a href="/wiki/Cryptista" title="Cryptista">Cryptista</a></li> <li><a href="/wiki/Ciliate" title="Ciliate">Ciliophora</a></li> <li><a href="/wiki/Cercozoa" title="Cercozoa">Cercozoa</a></li> <li><a href="/wiki/Discoba" class="mw-redirect" title="Discoba">Discoba</a></li> <li><a href="/wiki/Euglenozoa" title="Euglenozoa">Euglenozoa</a></li> <li><a href="/wiki/Jakobea" class="mw-redirect" title="Jakobea">Jakobea</a></li> <li><a href="/wiki/Haptista" title="Haptista">Haptista</a></li> <li><a href="/wiki/Hemimastigophora" title="Hemimastigophora">Hemimastigophora</a></li> <li><a href="/wiki/Malawimonada" class="mw-redirect" title="Malawimonada">Malawimonada</a></li> <li><a href="/wiki/Metamonada" class="mw-redirect" title="Metamonada">Metamonada</a></li> <li><a href="/wiki/Planomonada" class="mw-redirect" title="Planomonada">Planomonada</a></li> <li><a href="/wiki/Provora" title="Provora">Provora</a></li> <li><a href="/wiki/Rhizaria" title="Rhizaria">Rhizaria</a></li> <li><a href="/wiki/Stramenopiles" class="mw-redirect" title="Stramenopiles">Stramenopiles</a></li> <li><a href="/wiki/Telonemia" title="Telonemia">Telonemia</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Fungus" title="Fungus">Fungi</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Chytridiomycota" title="Chytridiomycota">Chytridiomycota</a></li> <li><a href="/wiki/Blastocladiomycota" title="Blastocladiomycota">Blastocladiomycota</a></li> <li><a href="/wiki/Neocallimastigomycota" title="Neocallimastigomycota">Neocallimastigomycota</a></li> <li><a href="/wiki/Glomeromycota" title="Glomeromycota">Glomeromycota</a></li> <li><a href="/wiki/Zygomycota" title="Zygomycota">Zygomycota</a></li> <li><a href="/wiki/Ascomycota" title="Ascomycota">Ascomycota</a></li> <li><a href="/wiki/Basidiomycota" title="Basidiomycota">Basidiomycota</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Plant" title="Plant">Plant</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Glaucophyta" class="mw-redirect" title="Glaucophyta">Glaucophyta</a></li> <li><a href="/wiki/Rhodophyta" class="mw-redirect" title="Rhodophyta">Rhodophyta</a></li> <li><a href="/wiki/Chlorophyta" title="Chlorophyta">Chlorophyta</a></li> <li><a href="/wiki/Charophyta" title="Charophyta">Charophyta</a></li> <li><a href="/wiki/Marchantiophyta" title="Marchantiophyta">Marchantiophyta</a></li> <li><a href="/wiki/Anthocerotophyta" class="mw-redirect" title="Anthocerotophyta">Anthocerotophyta</a></li> <li><a href="/wiki/Moss" title="Moss">Moss</a></li> <li><a href="/wiki/Lycopodiophyta" class="mw-redirect" title="Lycopodiophyta">Lycopodiophyta</a></li> <li><a href="/wiki/Pteridophyta" class="mw-redirect" title="Pteridophyta">Pteridophyta</a></li> <li><a href="/wiki/Cycadophyta" class="mw-redirect" title="Cycadophyta">Cycadophyta</a></li> <li><a href="/wiki/Ginkgophyta" class="mw-redirect" title="Ginkgophyta">Ginkgophyta</a></li> <li><a href="/wiki/Pinophyta" class="mw-redirect" title="Pinophyta">Pinophyta</a></li> <li><a href="/wiki/Gnetophyta" title="Gnetophyta">Gnetophyta</a></li> <li><a href="/wiki/Flowering_plant" title="Flowering plant">Flowering plant</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Animal" title="Animal">Animal</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Sponge" title="Sponge">Sponge</a></li> <li><a href="/wiki/Ctenophora" title="Ctenophora">Ctenophora</a></li> <li><a href="/wiki/Placozoa" title="Placozoa">Placozoa</a></li> <li><a href="/wiki/Cnidaria" title="Cnidaria">Cnidaria</a></li> <li><a href="/wiki/Xenacoelomorpha" title="Xenacoelomorpha">Xenacoelomorpha</a></li> <li><a class="mw-selflink selflink">Chordate</a></li> <li><a href="/wiki/Hemichordate" title="Hemichordate">Hemichordate</a></li> <li><a href="/wiki/Echinoderm" title="Echinoderm">Echinoderm</a></li> <li><a href="/wiki/Chaetognatha" title="Chaetognatha">Chaetognatha</a></li> <li><a href="/wiki/Kinorhyncha" title="Kinorhyncha">Kinorhyncha</a></li> <li><a href="/wiki/Loricifera" title="Loricifera">Loricifera</a></li> <li><a href="/wiki/Priapulida" title="Priapulida">Priapulida</a></li> <li><a href="/wiki/Nematode" title="Nematode">Nematoda</a></li> <li><a href="/wiki/Nematomorpha" title="Nematomorpha">Nematomorpha</a></li> <li><a href="/wiki/Onychophora" title="Onychophora">Onychophora</a></li> <li><a href="/wiki/Tardigrade" title="Tardigrade">Tardigrada</a></li> <li><a href="/wiki/Arthropod" title="Arthropod">Arthropoda</a></li> <li><a href="/wiki/Flatworm" title="Flatworm">Flatworm</a></li> <li><a href="/wiki/Gastrotricha" class="mw-redirect" title="Gastrotricha">Gastrotricha</a></li> <li><a href="/wiki/Orthonectida" title="Orthonectida">Orthonectida</a></li> <li><a href="/wiki/Dicyemida" title="Dicyemida">Dicyemida</a></li> <li><a href="/wiki/Rotifera" class="mw-redirect" title="Rotifera">Rotifera</a></li> <li><a href="/wiki/Acanthocephala" title="Acanthocephala">Acanthocephala</a></li> <li><a href="/wiki/Gnathostomulida" class="mw-redirect" title="Gnathostomulida">Gnathostomulida</a></li> <li><a href="/wiki/Micrognathozoa" class="mw-redirect" title="Micrognathozoa">Micrognathozoa</a></li> <li><a href="/wiki/Cycliophora" class="mw-redirect" title="Cycliophora">Cycliophora</a></li> <li><a href="/wiki/Nemertea" title="Nemertea">Nemertea</a></li> <li><a href="/wiki/Phoronid" title="Phoronid">Phoronid</a></li> <li><a href="/wiki/Bryozoa" title="Bryozoa">Bryozoa</a></li> <li><a href="/wiki/Entoprocta" title="Entoprocta">Entoprocta</a></li> <li><a href="/wiki/Brachiopoda" class="mw-redirect" title="Brachiopoda">Brachiopoda</a></li> <li><a href="/wiki/Mollusca" title="Mollusca">Mollusca</a></li> <li><a href="/wiki/Annelid" title="Annelid">Annelida</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:7em"><i><a href="/wiki/Incertae_sedis" title="Incertae sedis">Incertae sedis</a></i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"><i><a href="/wiki/Parakaryon" title="Parakaryon">Parakaryon</a></i></div></td></tr></tbody></table><div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /></div><div role="navigation" class="navbox" aria-labelledby="Taxon_identifiers3358" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Taxon_identifiers3358" style="font-size:114%;margin:0 4em"><a href="/wiki/Help:Taxon_identifiers" title="Help:Taxon identifiers">Taxon identifiers</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%;text-align: left;"><i>Chordata</i></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><span style="white-space:nowrap;"><a href="/wiki/Wikidata" title="Wikidata">Wikidata</a>: <span class="uid"><span class="external"><a href="https://www.wikidata.org/wiki/Q10915" class="extiw" title="wikidata:Q10915">Q10915</a></span></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Wikispecies" title="Wikispecies">Wikispecies</a>: <span class="uid"><span class="external"><a href="https://species.wikimedia.org/wiki/Chordata" class="extiw" title="wikispecies:Chordata">Chordata</a></span></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Animal_Diversity_Web" title="Animal Diversity Web">ADW</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://animaldiversity.org/accounts/Chordata/">Chordata</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Australian_Faunal_Directory" title="Australian Faunal Directory">AFD</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://biodiversity.org.au/afd/taxa/Chordata">Chordata</a></span></span></li> <li><span style="white-space:nowrap;">BioLib: <span class="uid"><a rel="nofollow" class="external text" href="https://www.biolib.cz/en/taxon/id14966">14966</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Barcode_of_Life_Data_System" title="Barcode of Life Data System">BOLD</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://bench.boldsystems.org/index.php/TaxBrowser_TaxonPage?taxid=18">18</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Catalogue_of_Life" title="Catalogue of Life">CoL</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://www.catalogueoflife.org/data/taxon/CH2">CH2</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Encyclopedia_of_Life" title="Encyclopedia of Life">EoL</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://eol.org/pages/694">694</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/EPPO_Code" title="EPPO Code">EPPO</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://gd.eppo.int/taxon/1CHORP">1CHORP</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Fauna_Europaea" title="Fauna Europaea">Fauna Europaea</a>: <span class="uid"><a rel="nofollow" class="external text" href="http://www.eu-nomen.eu/portal/taxon.php?GUID=urn:lsid:faunaeur.org:taxname:11996">11996</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Fauna_Europaea" title="Fauna Europaea">Fauna Europaea (new)</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://fauna-eu.org/cdm_dataportal/taxon/1700ebea-6b47-49a0-ab76-b82462c4c44b">1700ebea-6b47-49a0-ab76-b82462c4c44b</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Global_Biodiversity_Information_Facility" title="Global Biodiversity Information Facility">GBIF</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://www.gbif.org/species/44">44</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/INaturalist" title="INaturalist">iNaturalist</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://inaturalist.org/taxa/2">2</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Interim_Register_of_Marine_and_Nonmarine_Genera" title="Interim Register of Marine and Nonmarine Genera">IRMNG</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://www.irmng.org/aphia.php?p=taxdetails&id=148">148</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Integrated_Taxonomic_Information_System" title="Integrated Taxonomic Information System">ITIS</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=158852">158852</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/National_Center_for_Biotechnology_Information" title="National Center for Biotechnology Information">NCBI</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&id=7711">7711</a></span></span></li> <li><span style="white-space:nowrap;">NZOR: <span class="uid"><a rel="nofollow" class="external text" href="https://www.nzor.org.nz/names/406e3eca-a45f-43d7-ab69-43831f3412b4">406e3eca-a45f-43d7-ab69-43831f3412b4</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Open_Tree_of_Life" title="Open Tree of Life">Open Tree of Life</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://tree.opentreeoflife.org/taxonomy/browse?id=125642">125642</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/Paleobiology_Database" title="Paleobiology Database">Paleobiology Database</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://paleobiodb.org/classic/basicTaxonInfo?taxon_no=273393">273393</a></span></span></li> <li><span style="white-space:nowrap;"><a href="/wiki/World_Register_of_Marine_Species" title="World Register of Marine Species">WoRMS</a>: <span class="uid"><a rel="nofollow" class="external text" href="https://www.marinespecies.org/aphia.php?p=taxdetails&id=1821">1821</a></span></span></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374" /><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235" /><style 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