They are small bats, from in body length, and with grey, brown, or reddish fur. The skull is distinguished by a characteristic interorbital concavity, externally connected to a long slit that runs down the centre of their faces from between the eyes to the nostrils, and probably assists in
echolocation. They have large ears, and a complex
nose-leaf. Their tails end in a T-shape, formed from cartilage, a unique feature among mammals. Their
dental formula is: Nycterids have a reduction of the hand
phalanges: the 2nd digit has only
metacarpus, and the 3rd only two phalanges. The
pectoral girdle has parallel features to birds. The
sternum is strongly developed and the
mesosternum has a keel. ==Habitat and biology==