Agnatha

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Related to jawless fish: coelacanth, cartilaginous fish

Agnatha

aquatic, jawless, fish-like vertebrates characterized by fewer than two pairs of limbs (fins). The group is often given the status of a subphylum to separate it from other vertebrates with jaws which are included in the subphylum Gnathostomata. The Agnatha includes lampreys, hagfish, and the fossil OSTRACODERMI.
References in periodicals archive ?
Over 460 million years ago the first jawless fish swam in shallow seas of what was to become the Appalachian basin of North America.
ROSEBURG - A dam on the North Umpqua River has been modified to make the spawning migration easier for lamprey - a jawless fish that is often mistaken for an eel.
For their experiments, Lau and Morgan used as a model organism the sea lamprey, which is a jawless fish.
The sea lamprey, river lamprey and brook lamprey ( all kinds of jawless fish ( also find the weir impossible to negotiate as they migrate up stream to spawn.