LATE CRETACEOUS MULTITUBERCULATES OF THE CAROLINAS: MY...WHAT BIG TEETH YOU HAVE!
Two distinct taxa of multituberculates identified from the BCLA site are represented by the P4 and P2 of a Ptilodontoidean which appears transitional between the Laramidian genera Mesodma and Cimolodon, and the P4 of a cimexomyid comparable to Paracimexomys. The posterior half of a well-preserved multituberculate p4 has also been identified from the SP site, which appears to have cimolodontid affinities. It is of note that the preserved portion of the Stokes Pit p4 is nearly 4.5 mm in length, and if complete the tooth is inferred to have been at least 8 to 10 mm in length along the gingival margin based on the p4s of comparable taxa. This would make the SP taxon among the largest Cretaceous multituberculates known, similar in size to Meniscoessus major and Cimexomys magnus.
It has been suggested that land animals may have dispersed across eastern North America throughout the Late Cretaceous; however the presence of endemic taxa at both the Ellisdale site and the Carolina localities does not support this hypothesis. The eastern mammalian assemblages together with geological data suggest that Appalachia was an isolated continent from the Turonian onward, and thus may have been a refugium for relatively underived Early Cretaceous taxa that underwent vicariant speciation. If dispersal between Laramidia and Appalachia did take place, it could not have happened until the end of the Late Cretaceous, based on paleogeographic data.