Sclerorhynchoidei

Sclerorhynchoidei is an extinct, possibly paraphyletic suborder of rajiform rays with saw-like rostrums. They include the families Sclerorhynchidae and Ptychotrygonidae.[1] They were a rather long-lived group, living from the Cretaceous to the early Eocene, until they became extinct for unknown reasons and were replaced by their distant relatives the pristiformes.

Sclerorhynchoidei Temporal range: Cretaceous - Paleogene, 130-55 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Onchopristis numidus restoration
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Order:	Rajiformes
Suborder:	†Sclerorhynchoidei Cappetta, 1980
Families
†Sclerorhynchidae †Ptychotrygonidae †Ischyrhiza †Onchopristis †Schizorhiza Rajidae (?)

They are very closely tied to the extant family Rajidae and may be paraphyletic with respect to it, as some members generally considered to be of this group, such as Ischyrhiza, Onchopristis, and Schizorhiza may be more closely allied with Raijdae than with other members.[2]