Abstract:
Kannemeyeria simocephalus is probably the best known Middle Triassic dicynodont from South Africa and has been the standard against which other Triassic dicynodonts are compared. In the past studies have concentrated on the cranial morphology of K. simocephalus and how this affected Triassic dicynodont taxonomy and phylogeny. There has been little work on the postcranial anatomy of K. simocephalus, which remains poorly understood. This current study undertook a detailed descriptive analysis of the postcranial anatomy of K. simocephalus that lead to the identification of diagnostic characters of the postcranial skeleton. During the course of the analysis of the postcranial anatomy of K. simocephalus it was noted that material previously assigned to this taxon was significantly different from that recognised as K. simocephalus. Unfortunately, this material consists only of postcranial material and it is therefore referred to as Morphotype B rather than a new species of Kannemeyeria or as a new taxon from the Cynognathus Assemblage Zone (subzone B). A phylogenetic analysis was performed which included K. simocephalus and Morphotype B, and used cranial and postcranial characters. The preliminary phylogenetic results show that there are possibly two taxa of medium to large dicynodonts in the Cynognathus Assemblage Zone (subzone B); one a kannemeyeriid and the second a stahleckeriid. It has also evident that more attention needs to be paid to the study of the postcranial anatomy of Triassic dicynodonts, especially those from Africa and Asia.
