Abstract

We review the taxonomic history of traversodontid cynodont genera and species and the previous classifications and phylogenetic analyses of the group. 17 genera and 22 species are accepted as valid taxa within Traversodontidae. The phylogenetic relationships of traversodontids and other gomphodonts (including 6 trirachodontid species and Diademodon tetragonus) are analyzed based on 77 characters. Scalenodon angustifrons and (Andescynodon+Pascualgnathus) are found to be the most basal traversodontids. The three species of Scalenodon included in the analysis (Scalenodon angustifrons S. attridgei, and S. hirschsoni) do not form a clade, supporting recognition of a separate genus for the latter two. A monophyletic Gomphodontosuchinae is recovered, as suggested by previous analyses. The distribution of traversodontids is discussed, with Gondwana and especially Africa suggested as the ancestral area for Gomphodontia and Traversodontidae.