Black wildebeest
The black wildebeest or white-tailed gnu ("Connochaetes gnou") is one of the two closely related wildebeest species. It is a member of the genus "Connochaetes" and family Bovidae. It was first described in 1780 by Eberhard August Wilhelm von Zimmermann. The black wildebeest is typically in head-and-body length, and the typical weight is . Males stand about at the shoulder, while the height of the females is . The black wildebeest is characterised by its white, long, horse-like tail. It also has a dark brown to black coat and long, dark-coloured hair between its forelegs and under its belly.
Blue wildebeest
The blue wildebeest exhibits sexual dimorphism, with males being larger and darker than females. The blue wildebeest is typically in head-and-body length. The average height of the species is . While males weigh up to , females seldom exceed . A characteristic feature is the long, black tail, which is around in length. All features and markings of this species are bilaterally symmetrical for both sexes. The average life span is 20 years in the wild, and 21 years in captivity. The oldest known captive individual lived for 24.3 years.