Temporal range: Late Miocene–Early Pliocene
|An artist's illustration of Hoplitomeryx matthei|
The extinct Miocene-Pliocene mammal Hoplitomeryx looks quite like a deer. It had notable saber-like upper canine teeth (as the musk deer), a pair of horns above each additional eye orbit and a single central frontal horn. It lived during the Miocene and Early Pliocene on the island Gargano, which is now a peninsula on the east coast of the South of Italy. The findings suggest the skeletons into four size groups from small to large. All these groups have the same typical features of Hoplitomeryx. The hypothesis of an archipelago consisting of different islands, with its own species, yet is not confirmed.
Hoplitomeryx's largest variation in size was like that of an elk, but more elegant and graceful. It had large-scale diversity, probably due to adaptation, since when its Miocene ancestor colonized the island. The range of unoccupied niches promoted the formation of several types, which are fed by different types of plants. The absence of large predators and a limited amount of food in all the niches also help the development of various sizes.Hoplitomeryx was a deer-like ruminant with a pair of pronged horns above each orbit and one central nasal horn. Hoplitomerycidae are not the only horned deer, before the appearance of antlered deer, members of the deer family had horns. Another left-over of this stage is Antilocapra of North America, only survivor of a once successful group related to Bovidae. The diagnostic features of Hoplitomeryx are: one central nasal horn and a pair of pronged orbital horns, protruding canines, complete fusion of the navicocuboid with the metatarsal, distally closed metatarsal gully, a non-parallel-sided astragalus, and an elongated patella.