Cladoselachii

(paleontology) An order of extinct elasmobranch fishes including the oldest and most primitive of sharks.

An order of extinct elasmobranch fishes including the oldest and most primitive of sharks. Best known is Cladoselache (see illustration), of which complete specimens, including even muscle and other soft tissues, have been obtained from shales in the region of Cleveland, Ohio. Primitive features are broad-based paired fins, amphistylic jaw support, and absence of claspers. See also Elasmobranchii.

Cladoselache of the Late Devonian.