LARGE SHARK VERTEBRAE FROM THE LOWER CRETACEOUS DUCK CREEK OF TEXAS

Isolated teeth are the primary diagnostic material known from most sharks (Chondrichthyes: Elasmobrachii), as their cartilaginous skeleton rarely fossilizes. However, if parts of the skeleton such as vertebrae are well-calcified, they can be adequate paleoecological and taphonomic indicators. Here we report a new specimen known from several vertebral centra found in Dallas Area, Texas in the Duck Creek Formation (Lower Cretaceous, Albian). They are thought to belong to a lamnoid shark specimen. The centra appear to be, more specifically, from a cretoxyrhinid shark, though its taxonomic classification at the genus or species level is tenuous without associated teeth. This study calculates a total length conservative estimate of the specimen, which is possibly over 26 feet (8 meters). The size of the centra suggest that this specimen may represent the largest known cretoxyrhinid shark to date from the Duck Creek Formation.