No abstract

No abstract

A major question in Mesozoic biogeography is how the land-based dinosaurian radiation responded to fragmentation of Pangaea. A rich fossil record has been uncovered on northern continents that spans the Cretaceous, when continental isolation reached its peak. In contrast, dinosaur remains on southern continents are scarce. The discovery of dinosaurian skeletons from Lower Cretaceous beds in the southern Sahara shows that several lineages of tetanuran theropods and broad-toothed sauropods had a cosmopolitan distribution across Pangaea before the onset of continental fragmentation. The distinct dinosaurian faunas of Africa, South America, and Asiamerica arose during the Cretaceous by differential survival of once widespread lineages on land masses that were becoming increasingly isolated from one another.

A new traversodont cynodont, Plinth ogomphodon herpetairus, is described on the basis of a partial snout from Late Triassic strata of the Newark Supergroup exposed in the Deep River basin (Durham sub-basin) of North Carolina. In the structure of its upper postcanine teeth, Plinthogomphodon most closely resembles Boreogomphodon from the Upper Triassic (Carnian) of Virginia and Luangwa from the Middle Triassic (Anisian) of Zambia. It differs from these taxa only in some features of these teeth .