A new moradisaurine captorhinid from the Upper Permian (Lopingian) upper Madumabisa Mudstone Formation (Luangwa Basin) of Zambia

Captorhinidae are a diverse group of early or stem amniotes that were dominant components of early Permian terrestrial ecosystems, and one of the first reptiliomorphs to experiment with high-fiber herbivory. Moradisaurinae is a clade of large-bodied captorhinids that evolved by the middle Kungurian (∼280 Ma) and that possess multiple tooth rows on the maxilla and dentary. Here, we describe Amenoyengi mpunduensis gen. et sp. nov., a diminutive moradisaurine captorhinid from the Lopingian upper Madumabisa Mudstone Formation of the Luangwa Basin, Zambia and therefore one of the geologically youngest captorhinids. Amenoyengi bears a mosaic of cranial features including few maxillary tooth rows, a maxillary diastema, and caniniform teeth in the maxilla and dentary. An updated phylogenetic analysis places Amenoyengi mpunduensis as the sister taxon of Gansurhinus, a relationship supported by five unambiguous characters including a low number of maxillary tooth positions and tooth rows and the presence of a maxillary diastema. Our results indicate that moradisaurine interrelationships are influenced by ontogenetically variable characters, in agreement with recent studies. We review other late occurrences of Captorhinidae, and find that several, unnamed post-Cisuralian and small-bodied captorhinids can be referred to Moradisaurinae, and note that captorhinid specimens are unknown from later than the Wuchiapingian stage of the late Permian, and therefore the clade is not necessarily a victim of the end-Permian Mass Extinction.