Understanding tooth attachment and replacement in Bolosaurid Parareptiles.
Bolosaurid Parareptiles occupy a unique position in Amniote evolution. They were the first to develop a combination of a lower temporal fenestra and a massive coronoid process, probably for extensive oral processing. The highly heterodont marginal dentition is characterised by a reduction in the number of teeth from the ancestral Parareptile condition (e.g., two premaxillary, 10 maxillary, and 12 dentary teeth in the most complete specimen of Belebey vegrandis, and the presence of extensive tooth-on-tooth wear, with the most massive cheek teeth located posteriorly along the tooth row. First described from Texas specimens, the three Bolosaurid genera include two species of Bolosaurus, the smaller Bolosaurus. striatus and more massive Bolosaurus grandis from deposits in the Southern United States. Belebey consists of three species, including two Russian forms. Belebey maximi and Belebey vegrandis, and the Chinese Belebey chengi. Finally, the nearly complete Eudibamus cursoris of Germany represents the only other known taxon within the group.