Addax

The addax, also known as the white antelope or screwhorn antelope, is an antelope native to the Sahara and the only member of the genus Addax, first described scientifically by Henri de Blainville in 1816. Its spiral horns run 55 to 80 centimeters in females and 70 to 85 centimeters in males; its coat is greyish-brown with white hindquarters and legs and long brown hair on the head, neck and shoulders in winter, turning almost completely white or sandy blonde in summer, and males stand 105 to 115 centimeters at the shoulder against 95 to 110 centimeters for the generally smaller females.