[2] Aspidorhynchiformes has one family, which is divided into at least two genera:[3][4][5]: 57 Fossils range have been found in the United States, France, Italy, Russia, Saskatchewan, Alberta, North Dakota, Montana, Wyoming, and Uzbekistan.

A specimen from the Late Paleocene of North Dakota suggests they may have persisted into the early Cenozoic, although this may have just been reworked from earlier formations.

[12] Most aspidorhynchids were predatory fish, which is best exemplified by fossils of Aspidorhynchus from Germany that have been found entangled with those of the pterosaur Rhamphorhynchus, which they appear to have attacked and died with.

However, aspidorhynchids primarily fed on small fish and other vertebrates, with these attacks on pterosaurs appearing to be fatal mistakes.

[13] In contrast to other aspidorhynchids, the largest member of the family, the giant Richmondichthys from Australia, evolved clear adaptations for a planktivorous, filter-feeding lifestyle.