Sonitictis moralesi, gen. et sp. nov, a new hypercarnivorous and durophagous mustelid from middle Miocene Tunggur Formation, Inner Mongolia, China and its functional morphology

Abstract

ABSTRACT We name a rare, hypercarnivorous and durophagous mustelid Sonitictis moralesi, new genus and species, in honour of Jorge Morales for his contributions to carnivore palaeontology. Sonitictis moralesi is from the middle Miocene Tunggur Formation of Inner Mongolia, China (Tunggurian Land Mammal age). S. moralesi has a short and robust jaw that deepens slightly behind the m1 and possesses a shallow groove at its ventral surface. Dentally, it has robust premolars and highly hypercarnivorous m1 that has lost the metaconid and a trenchant talonid. Known by three jaw fragments, knowledge of this new mustelid is still poor and its relationship uncertain. However, based on its possession of a ventral groove, robust premolars and hypercarnivorous first molar, we tentatively place it in the subfamily Mellivorinae, which includes modern Mellivora capensis (honey badger) and extinct species of Eomellivora, plus others. We conducted mandibular force profile analyses on one S. moralesi specimen and compared bite force estimates to several specimens of E. piveteaui, E. wimani and M. capensis. The results suggest that Sonitictis likely was a more capable predator and consumer of vertebrate prey than the extant Mellivora, reaching the low end of the bite force estimates for the larger and more robust Eomellivora.