''Asarotus'' is an extinct genus of prehistoric marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

from the

Niobrara Formation The Niobrara Formation , also called the Niobrara Chalk, is a geologic formation in North America that was deposited between 87 and 82 million years ago during the Coniacian, Santonian, and Campanian stages of the Late Cretaceous. It is com ...

Nebraska Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Ka ...

, during the

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

. The type species, ''A. arcanus'' is only known from poorly preserved single specimen, which makes hard to classify existing orders of Cretaceous actinopterygians. It is thus classified as the only member of its family Asarotidae and order Asarotiformes. Some authorities consider it a late-surviving member of the " palaeonisciform" fishes.

References

Monotypic prehistoric ray-finned fish genera Late Cretaceous bony fish Late Cretaceous fish of North America Fossils of the United States Enigmatic ray-finned fish taxa Fossil taxa described in 1968 {{Cretaceous-fish-stub