The systematic position ofEquus hydruntinus,an extinct species of Pleistocene equid☆

Palaeolithic people commonly huntedEquus hydruntinus,an extinct species of equid whose cursorial body proportions suggest an adaptation to semi-arid conditions. Despite the frequency with which it is encountered in fossil deposits, only partial cranial remains have been reported until now. As a result, the systematic affiliation of the species remains a subject of controversy. Two nearly completeE. hydruntinuscrania are presented here for the first time. These skulls show thatE. hydruntinusis a distinct species, more closely related to the hemiones (Asiatic asses) than to any other equid. This suggests that the social organisation ofE. hydruntinusfollowed one of two known equid sociotypes: resource defense territoriality.