Micro‐computed tomography reveals a diversity of Peramuran mammals from the Purbeck Group (Berriasian) of England

摘要: :  The known sample of the important pretribosphenic mammal Peramus tenuirostris, housed in Natural History Museum (London, UK), was imaged using micro-computed tomography (CT). Substantial morphological diversity discovered, prompting establishment (and resurrection) additional taxa from within existing hypodigm tenuirostris: dubius comb. nov., Kouriogenys minor gen. nov. and Peramuroides tenuiscus et sp. Peramura are revised; this group is restricted to with clear evidence a fully functional upper molar embrasure for dominant lower talonid cusp (hypoconid), either through development wear facet 4 or differentiation distinct hypoconulid. most likely sister taxon Tribosphenida (including living marsupials placentals) represent morphotype, transitional between primitive lineages characterized by orthal shear (e.g. dryolestoids) those modern, multi-functional tribospheny. A very large masseteric foramen identified peramurans, but feature appears be autapomorphic uncertain function.