agnathan: Quick Facts

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Facts

Also Known As	Agnatha • jawless fish

Photos

Illustration of a Petromyzon, a jawless fish with an elongated, eel-like body and a rounded mouth, shown with a scale bar indicating 10 centimeters and 4 inches for size reference.

Illustration of a Myxine, or hagfish, showing its long, slender, eel-like body with smooth skin. A scale bar below indicates length in centimeters and inches for size reference.

A branching diagram shows the evolutionary relationships among fossil and modern jawless fishes (Agnatha), with illustrations of Petromyzon, Myxine, Pharyngolepis, Pteraspis, Hemicyclaspis, and Drepanaspis along a timeline from the Ordovician period to the present.

phyletic family tree for fishes

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Topics

Cephalaspidomorphi hagfish ostracoderm Osteostraci Eptatretidae Myxinidae Myxiniformes heterostracan Anaspida lamprey reptile Bird mammal chondrichthyan amphibian chimaera placoderm spiny shark bony fish 10 of the World’s Most Dangerous Fish

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