Osteologia craniana do Dicinodonte Rastodon Procurvidens (Dicynodontia: Therapsida) assistida por tomografia computadorizada

Abstract

Dicynodonts were important components of Permian and Triassic faunas, playing the role of small, medium and large herbivores. Its fossils are found all over the world, including Brazil. In Brazil, six genera are known: Endothiodon and Rastodon (both Permian); Dinodontosaurus, Stahleckeria, Jachaleria and Sangusaurus (Triassic taxa). The present contribution is twofold. First, I review the diversity of dicynodonts, with emphasis on Brazilian taxa. The second study reevaluates the cranial osteology of the dicynodont Rastodon procurvidens with the help of computed microtomography. In addition, the second study also uses cluster analysis on continuous data to assess the impact of proportions on grouping taxa. Additionally, a Principal Coordinate Analysis was conducted on the discrete morphological data, to the same effect. The study suggests that Rastodon procurvidens is a member of the Emydopoidea clade and that, therefore, the enigma of the origin of bidentalians remains a conundrum.