Palaeotragus ("Ancient Antelope") was a genus of very large, primitive okapi from the Miocene of Africa.
Palaeotragus primaevus is the older species, being found in early to mid-Miocene strata, while Palaeotragus germaini is found in Late Miocene strata.
P. primaevus is distinguished from P. germaini by having no pair of ossicones. It was also the smaller species, being a little under 2 meters at the shoulders. P. germaini had a pair of ossicones, and in life, it would have resembled either a short-necked, 3 meter tall giraffe, or a gargantuan okapi.
Source: Wikispecies, Wikipedia: All text is available under the terms of the GNU Free Documentation License