An early-diverging procolophonid from the lowermost Triassic of South America and the origins of herbivory in Procolophonoidea

The Procolophonoidea was the only parareptile clade to survive the end-Permian mass extinction, experiencing an important adaptive radiation during the Triassic. The flourishing of procolophonoid lineages in highly stressful post-extinction environments may be, at least in part, a result of their early adaptations to herbivory, which would eventually become the commonest feeding strategy in later representatives of the group. Although procolophonoids are comparatively diverse in the South African Lystrosaurus Assemblage Zone, only the globally widespread taxon Procolophon trigoniceps was thus far reported in South American deposits of similar age. Here we present a new procolophonid genus and species for the Lower Triassic Sanga do Cabral Formation of Brazil. Oryporan insolitus gen. et sp. nov. combines typical adaptations for herbivory with primitive character states that are peculiar to early procolophonoids. Accordingly, our phylogenetic results place the new species as an early-dive...