<?xml version="1.0" encoding="utf-8"?><metadata xmlns:dc="http://purl.org/dc/elements/1.1/"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:dcterms="http://purl.org/dc/terms/"><dc:title xml:lang="en">Cephalochordata</dc:title><dc:identifier>http://AATesaurus.cultura.gencat.cat/aat/getty_en?tema=31339671</dc:identifier><dc:language>en</dc:language><dc:publisher xml:lang="en">Getty Institute</dc:publisher><dcterms:created>2026-03-30 20:31:36</dcterms:created><dcterms:isPartOf xsi:type="dcterms:URI">http://AATesaurus.cultura.gencat.cat/aat/getty_en</dcterms:isPartOf><dcterms:isPartOf xml:lang="en">Tesaurus d&apos;Art i Arquitectura</dcterms:isPartOf><dc:format>text/html</dc:format> <dcterms:alternative xml:lang="en">Acrania</dcterms:alternative> <dcterms:alternative xml:lang="en">Cirrostomi</dcterms:alternative> <dcterms:alternative xml:lang="en">Leptocardia</dcterms:alternative> <dcterms:alternative xml:lang="en">Leptocardii</dcterms:alternative> <dcterms:alternative xml:lang="en">amphioxi</dcterms:alternative> <dcterms:alternative xml:lang="en">amphioxus</dcterms:alternative> <dcterms:alternative xml:lang="en">amphioxuses</dcterms:alternative> <dcterms:alternative xml:lang="en">cephalochorda</dcterms:alternative> <dcterms:alternative xml:lang="en">cephalochordates</dcterms:alternative> <dcterms:alternative xml:lang="en">lancelet</dcterms:alternative> <dcterms:alternative xml:lang="en">lancelets</dcterms:alternative> <dc:description xml:lang="en"><![CDATA[ Small, fishlike marine invertebrates that are probably the closest living relatives of the vertebrates. Their distinguishing characteristics include a notochord that extends the entire body length, with tip anterior to nerve cord; an atrium that is a single cavity with single ventral opening, but no heard; segments that are well developed; a head poorly developed; and no paired fins. ]]></dc:description></metadata>