Southeastern Section - 54th Annual Meeting (March 17–18, 2005)

Paper No. 6
Presentation Time: 9:50 AM

THE PLEISTOCENE VERTEBRATE FAUNA OF CLARK QUARRY, BRUNSWICK, GEORGIA


BAHN, Robert A. and MEAD, Alfred J., Biological and Environmental Sciences, Georgia College and State Univ, Milledgeville, GA 31061, bobbahn1@hotmail.com

Fossil localities containing associated and semi-articulated vertebrate material are exceptionally rare in Georgia. Excavations at Clark Quarry near Brunswick, Georgia have produced an array of in situ Pleistocene vertebrate fossils. Clark Quarry is located along the abandoned Brunswick Canal, a man-made waterway constructed between 1838 and 1839. The locality lies within the Princess Anne terrace of the Georgia coastal plain. The fossiliferous horizon is approximately one meter thick and composed of a well sorted, sub-rounded to subangular, medium to coarse grained quartz arenite lacking peat and muddy sediment. Directly below this horizon is a marine sand layer containing various taxa such as bivalves, gastropods, chondrichthyans, and drum fish (Sciaenidae). The vertebrate macrofossils are dominated by the Columbian mammoth (Mammuthus columbi) and the giant bison (Bison latifrons). Mammuthus columbi is represented by a juvenile partial jaw with one deciduous cheek tooth, adult tooth plates and tusk fragments, numerous cervical and thoracic vertebrae, sternal elements, ribs, one scapula, one humerus, one radius, one tibia, and numerous podials and metapodials. Bison latifrons is represented by a nearly complete skull with attached horn-cores, numerous cervical, thoracic, lumbar, and caudal vertebrae, numerous ribs, two scapulae, four humeri, two radio-ulnae, one femur, one tibia, and numerous podials. Additional mammalian taxa include white-tailed deer (Odocoileus virginianus) and arvicoline rodents. Birds are represented by a minimum of five orders including: Pelecaniformes, Anseriformes, Gruiformes, Charadriiformes, and Passeriformes. The herpetofauna includes the giant land tortoise (cf. Hesperotestudo crassiscutata), alligator (Alligator mississippiensis), emydid turtles, water snakes (Nerodia sp. and Thamnophis sp.) and ranid frogs. The fish fauna includes gar (Lepisosteus sp.), drum fish, chondrichthyans, and additional unidentified taxa. The vertebrate fauna and sedimentology of Clark Quarry suggests the fossils were deposited in or along a low energy coastal stream flowing into a back-barrier tract.