Topi, scientific name, Damaliscus lunatus, is medium sized antelope with rusty red color and black legs and chest. Topi have the short neck and elongated face typical of the Alcelaphinae. It is distinguished from its look-alike, the hartebeest by its darker coloration and absence of sharply angled horns. The muzzle is long and narrow with a black strip running from forehead to the tip of the nose. The topi stands 3.3 to 4.3 tall at the shoulder and is 5 to 7 feet in length. Weight is between 113 and 158 kg. Both sexes have strong, deeply ringed horns. Although Topis used to be one of the most common ungulates over many African grasslands, they probably no longer occur in the northeastern end of Nigeria where they used to be but may still exist as vagrants. The D. l. korrigum subspecies that used to exist in Nigeria is reddish gray, with a black face, and a black stripe on the outside of the legs above the knees.
Topi can reach top speeds of over 70 km/h, but are so curious that they have been known to stand and stare while members of their herd are shot. They are most famous for their sentry position, in which a single animal will stand on a termite mound for hours surveying the surrounding territory. Males act differently depending on the social organization of the group. In a small herd they are very protective of the females. They alert the females and young of approaching danger and defend them against predators. The diet of topis is composed almost entirely of grass. Topis do not have to drink if the grass they are eating is water saturated. If they are eating dry grass, then they must drink water every day or two. The competition for food has probably caused the seeming replacement of its population with those of cattle.
After an average gestation period of 8 months, the altricial newborn calf lies up for a few days before joining its mother. It becomes sexually mature by some 639 days if female, and lives for up to 15 years.