jawless

jawless: fishes lacking jaws are vastly outnumbered by jawed fishes. The living Agnatha, hagfishes and lampreys, number about 108 species. This is a paraphyletic group and, as well as lacking jaws in contrast to the jawed fishes, also lacks pectoral and pelvic fins, has one or two semicircular canals, no scales, no bones, no vertebral centra but only a notochord, and pores rather than slits as gill openings

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jawless fish — [jô′lis] n. any of a class (Agnatha) of fishes with a cartilaginous skeleton, an eel like body, and a circular, sucking mouth lacking jaws, consisting of the lampreys and hagfishes … English World dictionary
jawless fish — cyclostome. [1965 70; JAW1 + LESS] * * * any of numerous primitive, fishlike, jawless vertebrates comprising the class Agnatha, which includes the lampreys, hagfishes, and some extinct groups. See hagfish; lamprey. * * * … Universalium
jawless fish — noun eel shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms • Syn: ↑jawless vertebrate, ↑agnathan • Hypernyms: ↑aquatic vertebrate • Hyponyms: ↑ostracoderm, ↑ … Useful english dictionary
jawless vertebrate — noun eel shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms • Syn: ↑jawless fish, ↑agnathan • Hypernyms: ↑aquatic vertebrate • Hyponyms: ↑ostracoderm, ↑heterostrac … Useful english dictionary
jawless — See jaw. * * * … Universalium
jawless — adjective Lacking a jaw … Wiktionary
jawless — jaw·less jȯ ləs adj having no jaw … Medical dictionary
jawless — adj. lacking a jaw (especially a lower jaw) … English contemporary dictionary
jawless — jaw·less … English syllables
jawless — adjective of animals having no jaw • Ant: ↑jawed … Useful english dictionary

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