jawless vertebrate

Definitions of jawless vertebrate
  1. noun
    eel-shaped vertebrate without jaws or paired appendages including the cyclostomes and some extinct forms
    synonyms: agnathan, jawless fish
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    types:
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    ostracoderm
    extinct fish-like jawless vertebrate having a heavily armored body; of the Paleozoic
    heterostracan
    extinct jawless fish with the anterior part of the body covered with bony plates; of the Silurian and Devonian
    cephalaspid, osteostracan
    extinct jawless fish of the Devonian with armored head
    anaspid
    extinct small freshwater jawless fish usually having a heterocercal tail and an armored head; of the Silurian and Devonian
    conodont
    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 cyclostomes
    cyclostome
    primitive aquatic vertebrate
    lamper eel, lamprey, lamprey eel
    primitive eellike freshwater or anadromous cyclostome having round sucking mouth with a rasping tongue
    hag, hagfish, slime eels
    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
    Petromyzon marinus, sea lamprey
    large anadromous lamprey sometimes used as food; destructive of native fish fauna in the Great Lakes
    Myxine glutinosa
    typical hagfish
    eptatretus
    a fossil hagfish of the genus Eptatretus
    Myxinikela siroka
    fossil hagfish of the Pennsylvanian period (c. 300 million years ago) that resembled modern hagfishes
    type of:
    aquatic vertebrate
    animal living wholly or chiefly in or on water
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