There aren't separate "species" of vargr, but they do vary physically depending on where they originate. This is genetic - a vargr with predominantly African ancestry will have africanized features no matter where he shapeshifts.

Compared to typical European vargr, africanized vargr are slimmer and longer-legged, with a shorter pelt, these being adaptations to cope with extreme heat. Their jaws are shorter and broader, and their mane is restricted to a strip running down the spine. African vargr are more diurnal than Euro vargr, and consequently have a spotted pattern - people would refer to them as wereleopards or werehyenas, although they don't really strongly resemble either animal.

Note that most vargr are European and African. Shapeshifters are virtually unknown in Asia and in America - the shapeshifter traditions in these areas are more akin to trickster tales. So sorry, no 'kitsune' or 'skinwalkers'. Central European vargr are referred to as werewolves, further north they tended to be even bigger and shaggier (to conserve heat) and were called bersekrers (were-bears). It's all the same critter, though.