A new skeleton of a scaloposaurian therocephalian (Therapsida, Eutheriodontia) from the Late Permian of the Karoo Basin

MABOTHA, M.E.; ABDALA, F.; GESS, R.

Johannesburgo

Conferencia; 18th Biennial Conference of the Palaeontological Society of Southern Africad; 2014

Palaeontological Society of southern Africa

Therocephalians are a diverse group of extinct mammal-like therapsids that were abundant in the Karoo of South Africa from the Middle Permian to the Middle Triassic. This group has several representatives in the Late Permian Dicynodon Assemblage Zone. It is difficult to give a precise number of therocephalian taxa represented in this assemblage zone because seven of the 13 therocephalians are member of the Scaloposauria, a group in need of a taxonomical revision. A new specimen representing an almost complete skeleton of a medium-sized therocephalian was collected from the farm Biscuitfontein in the Karoo, at levels corresponding to the top of the Dicynodon Assemblage Zone. The new specimen is member of the Scaloposauria and bears a resemblance to Ictidosuchus longiceps and Lycideops longiceps, both representatives from the Dicynodon Assemblage Zone. These taxa are represented by one to two specimens without any knowledge of their postcranium. The objective of this contribution is the determination of the taxonomic identity of the new therocephalian specimen. In addition, we also will explore quantitative differences in the limb bones (stylopodium vs zeugopodium) of therocephalians of different sizes and of basal non-mammaliaform cynodonts.