The common patas monkey (Erythrocebus patas), also known as the wadi monkey or hussar monkey, is a ground-dwelling monkey distributed over semi-arid areas of West Africa, and into East Africa. The male common patas monkey grows to 60 cm (24 in) to 87 cm (34 in) in length, excluding the tail, which measures 75 cm (30 in). Adult males are considerably larger than adult females, which average 49 cm (19 in) in length. Adult males average 12.4 kg (27.3 lb) and adult females 6.5 kg (14.3 lb), showing a high degree of sexual dimorphism. Reaching speeds of 55 km/h (34 mph), it is the fastest runner among the primates. The life span in the wild can be up to about 20 years. (Source: Wikipedia.org, CC BY-SA)