The water deer is a species that evolved growing a pair of tusks instead of antlers like normal deer. The water deer (Hydropotes inermis) is a small deer superficially more similar to a musk deer than a true deer. Native to China and Korea, there are two subspecies: the Chinese water deer (Hydropotes inermis inermis) and the Korean water deer (Hydropotes inermis argyropus).