Revision of the rhinoceros remains (Rhinocerotidae, Mammalia) from the late Pliocene of Etouaires (Auvergne, France) and the morphological distinction between the postcranial bones of Stephanorhinus elatus and S. etruscus

This work revises the rhinoceros remains from the well-known early Villafranchian locality of Étouaires (Auvergne, France), which have been collected on multiple occasions since the late 18th century. The species Stephanorhinus elatus and S. etruscus are present, both represented mainly by postcranial elements. To identify them, a detailed preliminary analysis of the morphological differences between the postcranial skeletons of the two species has been undertaken, using the material from Vialette (Haute-Loire, early Villafranchian) and Senèze (Haute-Loire, early late Villafranchian) as comparison for S. elatus and S. etruscus respectively, plus some specimens of S. etruscus from Upper Valdarno (Tuscany, middle Villafranchian). These localities have been chosen because they all yielded only one of the two species. The morphological distinction between the two species is not easy, since the interspecific variability often overlaps and includes polymorphic characters. However, a few diagnostic characters are described, and intra-specific variability has been investigated as much as possible with the fossil material under investigation.