Musk deer can refer to any one, or all seven, of the species that make up "Moschus", the only extant genus of the family Moschidae.

Despite being commonly called deer, they are not true deer belonging to the family Cervidae but rather their family is closely related to Bovidae, the group that contains antelopes, bovines, sheep and goats. The musk deer family differs from cervids, or true deer, by lacking antlers and preorbital glands also, possessing only a single pair of teats, a gallbladder, a caudal gland, a pair of canine tusks and a musk gland.

Musk deer live mainly in forested and alpine scrub habitats in the mountains of southern Asia, notably the Himalayas. Musk deer are herbivores, living in hilly, forested environments, generally far from human habitation. Like true deer, they eat mainly leaves, flowers, and grasses, with some mosses and lichens.

Musk deer have been hunted for their scent glands, which are used in perfumes. The glands can fetch up to $45,000/kg on the black market. It is rumored that ancient royalty wore the scent of the musk deer and that it is an aphrodisiac.

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