PRELIMINARY ANALYSIS OF THREE LATE CRETACEOUS MARINE VERTEBRATE ASSEMBLAGES FROM THE PEEDEE FORMATION AT ALLISONS FERRY, CAINS LANDING, AND BURCHES FERRY, FLORENCE COUNTY, SOUTH CAROLINA

Late Cretaceous (Maastrichtian) marine vertebrate faunas were recovered from Peedee Formation strata exposed along the west bank of the Great Pee Dee River at Burches Ferry, Cains Landing, and Allisons Ferry, Florence County, South Carolina. Peedee Formation strata are oldest at Burches Ferry and youngest at Allisons Ferry, with Cains Landing stratigraphically in between. Most fossils were recovered by disaggregating bulk matrix collected at each site, but some specimens were surface collected.

Our fossil vertebrate sample includes several different mosasaurs, a chelonioid turtle, eight osteichthyans and twenty-two elasmobranchs. Some species have previously been reported from the Peedee Formation at Burches Ferry, but most were heretofore not known to occur in South Carolina. New Maastrichtian elasmobranch records for the state include Lonchidion sp., Heterodontus sp. cf. H. granti, Squatina sp., Chiloscyllium sp., Cantioscyllium sp., Plicatoscyllium derameei, Plicatoscyllium antiquum, ?Pararhincodon sp., Carcharias holmdelensis, Serratolamna serrata, Palaeogaleus sp., Squatigaleus sulphurensis, Scylliorhinus ivagrantae, Rhinobatos uvulatus, Pseudohypolophus sp., Raja farishi,, Borodinopristis sp., Ptychotrygon vermiculata, Texatrygon sp., Hamrabatis weltoni, Texabatis corrugatus, and Rhombodus binkhorsti. The eight osteichthyans represent new records, including Enchodus gladiolus, Enchodus petrosus, Paralbula casei, Anomoeodus phaseolus, Hadrodus sp., Lepisosteidae indet., and Dercetidae indet. Most of these taxa were originally reported from Texas and have since been identified in North Carolina, so their discovery in SC may therefore not be surprising. However, the SC material provides additional data on the paleoenvironments inhabited by these taxa, as well as the paleobiogeographic distribution of the species.

Each of the exposed beds at Allisons Ferry have been sampled, and further investigation of the Peedee Formation will include systematic sampling of the entire vertical exposure at Burches Ferry and Cains Landing. Comparison of the paleofaunas occurring at each of these sites will provide a better understanding of any changes in marine vertebrate assemblages, laterally (geographic) and vertically (temporal), that occurred during the Maastrichtian.