Taxonomic re-assessment and phylogenetic relationships of miocene homonymously spiral-horned antelopes

Abstract

A morphological reappraisal of Middle Miocene and Early Pliocene antelopes with homonymously twisted horncores (i.e., with the left horncore twisted clockwise from the base up) and an additional re-description of some critical Greek specimens allows a revision of the current taxonomy at the species and genus level. A parsimony analysis recognizes Hispanodorcas, Oioceros, Samodorcas, Samotragus, Paraoioceros, and Urmiatherium as distinct lineages of the subtribe Oiocerina. The latter emerged during the Astaracian (ca. 14-11.5 Ma), and radiated in Eurasia during the mid-late Vallesian (ca. 10-9 Ma), resulting in a great variety of genera with unique combinations of morpho-ecological adaptations. The suprageneric relationships of Oiocerina are poorly understood, but their closest ancestors possibly lie within or close to the Middle Miocene "hypsodontines", and inside Antilopinae. © 2014 D.S. Kostopoulos.