Fauna of South Africa the world’s seventeen megadiverse countries. In the extreme northwest of the country is true desert, which is the southernmost end of the Namib desert, a desert that is at least 55 million years old, making it the oldest desert in the world. This arid corner intergrades into the extensive semi-arid Karoo found across much of South Africa, covering the Northern Cape and into parts of the Western Cape, Eastern Cape and the Free State. This biome used to be extensive grassland in the past, but has become dominated by small shrubs and succulents due to centuries of overgrazing. To the
Karoo they are the Tankwa Karoo, the Moordenaarskaroo, the Koup, the Vlakte, and the Camdeboo Plains. The Hantam, Kareeberge, Roggeveld, and uweveldare the better known subregions of the Upper Karoo, though most of it is simply known as the Upper Karoo, especially in the north. The Little Karoo’s boundaries are sharply defined by mountain ranges to the west, north, and south. The road between Uniondale and Willowmore is considered, by convention, to form the approximate arbitrary eastern extremity of the Little Karoo. Its extent is much smaller than that of the Great Karoo. Locally, it is usually called the "Klein Karoo",