The systematic position of Hoplitomerycidae (Ruminantia) revisited

Hoplitomeryx Leinders, was originally described only on cranial characters. The type specimens were found during the 1970's in karstic fissure fillings, most likely of Messinian age, in Gargano (Apulia, southeastern Italy), between Poggio Imperiale (41°49′30′′ N, 15°21′58′′ E) and Apricena (41°47′06′′ N, 15°26′41′′ E). During the 1990's Hoplitomeryx remains were also discovered in lower Tortonian layered calcarenites near Scontrone (Abruzzo, central Italy: 41°45′15.55′′ N, 14°02′13.23′′ E). The skull fragments, teeth, and jawbones from both localities have been examined. The dental characters had never been described before, and also some maxillaries and jawbones were not part of the original sample that was analyzed to establish the genus. Because they possess two lacrimal orifices and closed metatarsal gulley, hoplitomerycids have been linked more closely with Cervids, and accommodated in Cervoidea. A cladistic analysis of a character-taxon matrix of 121 features (48 cranial, 51 dental and 22 postcranial characters) is performed. The analysis shows that hoplitomerycids stem either between antilocaprids and bovids, or antilocaprids and giraffids. They are not linked directly with cervids. Hoplitomerycids likely stemmed from a primitive ruminant stock, perhaps around 29 Ma when a land-bridge connected the Abruzzo-Apulia platform with the Balkans across the Adriatic Sea. In the new land hoplitomerycids developed a mosaic of apomorphic and homoplastic (convergent) character states that recall those found in other higher ruminants.