THE OLDEST SCLERORHYNCHID SAWFISH (RAJIFORMES: SCLERORHYNCHIDAE) FROM THE LOWER CRETACEOUS OF TEXAS

摘要

The earliest known oral teeth of the sclerorhynchid sawfish, Onchopristis sp., are reported from the Early Cretaceous of Central Texas. These teeth were recovered from the uppermost Glen Rose Formation of the Trinity Group. In addition to the sawfish teeth, this bed contains a concentration of disarticulated fish remains, selachian teeth and denticles, crocodile teeth, and plant remains. Previous reports place the earliest occurrence of sclerorhynchids in the overlying Fredericksburg Group. These teeth move the earliest known occurrence of sclerorhynchid sawfish back several million years.