Revision of the Tanzanian dicynodont (Therapsida: Anomodontia) from the Permian Usili Formation.

A single species of the dicynodontoid dicynodont is currently recognized from the late Permian Usili Formation of Tanzania: Haughton, 1932. Restudy of the known Tanzanian materials of . demonstrates that they represent two distinct morphotypes, here considered separate taxa. The holotype of . is not referable to and instead is transferred to the genus (but retained as a valid species, comb. nov.). A number of published dicynodontoid specimens from the Usili Formation, however, are referable to , and are here recognized as a new species ( sp. nov.) can be distinguished from its South African congener by the presence of an expansion of the squamosal and jugal beneath the postorbital bar and a curved, posterolateral expansion of the squamosal behind the temporal fenestra. Inclusion of and . in a phylogenetic analysis supports their referral to and (respectively). These results indicate higher basinal endemism in large late Permian dicynodonts than previously thought, a sharp contrast to the cosmopolitanism in the group in the earliest Triassic.