Which spiral-horne African antelope was first described by George French Angas in 1849?

The nyala is a spiral-horned antelope native to southern Africa. It is a species of the family 'Bovidae'. It was first described in 1849 by George French Angas (25 April 1822- 4 October 1886), who was an English explorer, naturalist, painter and poet, emigrated to Australia.

The body length of nyala is 135-195 cm (53-77 in), and it weighs 55-140 kg (121-309 lb). The coat is rusty or rufous brown or slate gray, often tinged with blue, in adult males. Females and young males have ten or more white stripes on their sides. Only males nyala have horns, 60-83 cm (24-33 inch) long and yellow tipped. It exhibits the highest sexual dimorphism among the spiral-horned antelopes. The sexual dimorphism is the condition where the two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs.

The main predators of the nyala are lion, leopard and Cape hunting dog, while the baboons and raptorial birds hunt for the juveniles. The males are highly prize as game animals in Africa. Nyala is the accepted genus, it is still considered as a species of 'Tragelaphus'. It was found that Vitamin E levels varied during nutritional stress, where old adults, mostly females died in more numbers.