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Dicynodont therapsids were near-ubiquitous components of Permo-Triassic terrestrial faunas, but the morphology of many of the nominal species remains poorly understood. Here we provide a detailed redescription of the cranium of the poorly known Dolichuranus primaevus from the Middle Triassic Omingonde Formation of Namibia, based on both the holotype and previously undescribed referred specimens. We identify a number of autapomorphic characters of D. primaevus and provide a revised taxon diag-

A large temnospondyl mandible from the Lystrosaurus Assemblage Zone (Early Triassic) of South Africa is referred to the higher-level taxon Trematosauridae. The mandible is remarkably similar to that described for Trematosaurus from the Middle Buntsandstein of Germany, a genus closely related to the South African Trematosuchus, for which the mandible is unknown. However, the mandible cannot be referred unequivocally to either of these taxa. Trematosuchus is considered to be restricted to the lowermost subzone of the overlying Cynognathus Assemblage Zone, which, based principally on the temnospondyl and therapsid fauna, is considered to be of Upper Olenekian age. The mandible described here extends back the range of the Trematosauridae to the underlying Lystrosaurus Assemblage Zone and argues against the long-held notion of a sharp palaeontological break between the faunas of the Lystrosaurus and Cynognathus Assemblage zones. It also supports the hypothesis that the Lystrosaurus Assemblage Zone extended up to the Upper Olenekian.

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