Coilopoceras

Coilopoceras is a compressed, involute, lenticular ammonitid from the Upper Cretaceous with a narrow venter and raggedy ammonitic suture; type of the Coilopoceratidae, a family in the Acanthoceratoidea of the suborder Ammonitina.

Coilopoceras has an established range from the lower Turonian to the Coniacian in the Upper Cretaceous and may have appeared as low as the upper Cenomanian. Its distribution is widespread, from western North America through northern Africa and Europe to the Middle East.