jawless fish

American  

noun

1. cyclostome.

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jawless fish Scientific  

/ jô′lĭs /

1. Any of various primitive fish of the class Agnatha that lack jaws. Living jawless fish (lampreys and hagfish) have a long, cylindrical body and a cartilaginous skeleton. The numerous extinct species were often heavily armored and are among the earliest vertebrate fossils known. Jawless fish occupy an intermediate evolutionary position between primitive chordates and jawed fish.

2. Also called agnathan

3. See more at cyclostome Compare bony fish cartilaginous fish

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Etymology

Origin of jawless fish

First recorded in 1965–70; jaw ¹ + -less

Example Sentences

Early jawless fish were likely to have used bony projections surrounding their mouths to modify the mouth's shape while they collected food.

From Science Daily

By comparing this feature in the jawed fish fossil with the brain case features of their precursors, the jawless fish, he and the team discovered new ways the two could be compared.

From Science Daily

In recent years paleontologists have even connected the Tully Monster to jawless fish such as lampreys, which have a backbonelike structure.

From Scientific American

Lampreys are a jawless fish, older than dinosaurs, that look like their distant relative, the eel, according to the state Department of Fish and Wildlife.

From Seattle Times

They include ancient groups like jawless fish, lineages of early jawed fish called placoderms, ascendant newcomers like cartilaginous and bony fish and the first fishes to hop onto land.

From New York Times