Okapi, hoofed mammal of the giraffe family. A very shy animal, it lives in the dense forests of equatorial Africa and was not discovered until 1900. It is brown with zebra-like stripes on its legs and hindquarters. The tongue is extremely long. Males have small, hair-covered horns. Height: to 1.6m at the shoulder. Family Giraffidae; species Okapia johnstoni.