A NEW OCCURANCE OF POLYACRODUS, (CHONDRICHTHYES; POLYACRODONTIDAE) FROM THE LATE CRETACEOUS CARLILE SHALE (TURONIAN) OF GRANT COUNTY, SOUTH DAKOTA

Three teeth of the Hybodont shark Polyacrodus were recovered from the Dakota Rose granite quarry from Milbank, South Dakota in the Carlile Shale (Late Cretaceous; Turonian) deposits. Two complete teeth are well preserved measuring 17mm in length with a crown height of 6mm with root bases intact. The third is a nearly complete specimen with a partially complete root base. The teeth were collected in association with plesiosaur vertebrae, teeth and post cranial elements, numerous fish species, abundant shark and ray teeth and vertebrae and a single mosasaur tooth. These specimens represent a new occurrence of Polyacrodus from the Carlile Shale as well as the Northernmost occurrence of this species in the United States to date. These teeth further the understanding of the diversity of the Cretaceous Inland Sea and its near-shore marine fauna.