jawless fish

jawless fish

n. Any of various elongated marine and freshwater fishes lacking jaws and paired appendages, sometimes thought to constitute the taxon Agnatha. The only extant jawless fishes are the hagfishes and the lampreys.

jaw′less fish`

n. 1. Also called cyclostome. any fish of the class Agnatha (and order Cyclostomata), characterized by a circular sucking mouth that lacks jaws. 2. ostracoderm. [1965–70]

jaw·less fish

(jô′lĭs) Any of several primitive fish that lack a jaw and resemble the eels. Jawless fish include the lampreys and hagfish. Compare bony fish, cartilaginous fish.

Thesaurus

Noun

1.

jawless fish - eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct formsagnathan, jawless vertebrateaquatic vertebrate - animal living wholly or chiefly in or on waterAgnatha, superclass Agnatha - superclass of eel-shaped chordates lacking jaws and pelvic fins: lampreys; hagfishes; some extinct formsostracoderm - extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoicheterostracan - extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devoniancephalaspid, osteostracan - extinct jawless fish of the Devonian with armored headanaspid - extinct small freshwater jawless fish usually having a heterocercal tail and an armored head; of the Silurian and Devonianconodont - small (2 inches long) extinct eellike fish with a finned tail and a notochord and having cone-shaped teeth containing cellular bone; late Cambrian to late Triassic; possible predecessor of the cyclostomescyclostome - primitive aquatic vertebratelamper eel, lamprey, lamprey eel - primitive eellike freshwater or anadromous cyclostome having round sucking mouth with a rasping tonguehagfish, slime eels, hag - eellike cyclostome having a tongue with horny teeth in a round mouth surrounded by eight tentacles; feeds on dead or trapped fishes by boring into their bodies