Southeastern Section - 65th Annual Meeting - 2016

Paper No. 22-2
Presentation Time: 8:30 AM

LATE CRETACEOUS MAMMALS OF THE CAROLINAS


DENTON Jr., Robert K., Geology, GeoConcepts Engineering Inc, 19955 Highland Vista Drive, Suite 170, Ashburn, VA 20147, rdenton@geoconcepts-eng.com

The mammalian taxa of the Late Cretaceous have been the subject of considerable interest and study since the 19th century. Since that time, thousands of specimens and hundreds of taxa have been described worldwide, however until recently the total of Late Cretaceous mammalian fossils from eastern North America was limited to tiny number of fragmentary and worn specimens. A proximal femoral fragment from New Jersey, a putative eutherian tooth from Mississippi, a multituberculate incisor and metatherian premolar from Texas comprised all that was known of the mammalian fauna of the eastern North American island continent of “Appalachia”.

In 1992, the discovery of three mammalian teeth was described from the Ellisdale Site of Monmouth County, New Jersey, consisting of a metatherian M3, a multituberculate I2 and a multituberculate P4. Since that time, over 20 isolated mammalian teeth have been identified from the Ellisdale Site, nearly quintupling the total of known specimens from the Late Cretaceous of Eastern North America. Augmenting the finds made at Ellisdale additional mammalian teeth have been discovered at Late Cretaceous sites in the Carolinas. A cimexomyid P4, and a neoplagiaulacid P3 and P4 have been found at the Elizabethtown Landfill Site in North Carolina, along with the posterior half of a cimolomyid P4 discovered at the Stokes Pit Site in South Carolina. To date all unequivocal mammalian specimens found in the Late Cretaceous of the Carolinas have been limited to multituberculates. Although they show similarities to the Ellisdalian mammalian fauna, the Carolina specimens are all significantly larger. The cimolomyid P4 from South Carolina is among the largest multituberculate mandibular premolar “buzz saw” teeth ever found, larger than both Meniscoessus major (Russell) and Cimexomys magnus (Sahni) from the Judith River Formation (Campanian) of the United States and Canada.

It is our hope that further prospecting in the coastal plain regions of the southeastern Atlantic and Gulf Coast regions will eventually bring more mammalian specimens to light, adding to our understanding of the terrestrial faunas of the Late Cretaceous continent of Appalachia, and assist in defining the distribution and dispersal patterns of Laurasian mammals during the Late Cretaceous and Early Paleogene.