Cyprinids of Africa

Africa straddles the tropics and contains a wide range of biotopes from rain forests to major deserts. Temperate climates occur only in the extreme south and in restricted zones of high altitude. The western half of the continent is well watered within tropical latitudes, but rainfall is seasonal in the north, east and south. Dry desert or semi-desert conditions prevail in the north and to the south-west. On a broad scale the continental landscape comprises an elevated plateau impressed with the basins of major drainages of the Nile, Niger, Zaire, Zambezi and the Orange (Roberts, 1975; Beadle, 1981). The palaeohistorical view is that some of these basins were formerly major areas of endorheic drainage, possibly forming immense inland lakes that were later captured by encroaching coastal systems (Beadle, 1981). There are few extant large endorheic drainages in Africa, but Lake Chad and the Okavango basins are notable examples. The Great Lakes of Central and East Africa are prominent features and their faunal histories are closely interwoven with the geomor-phological evolution of the East African Rift system. Drainage evolution throughout Africa is intricately associated with the distribution patterns of freshwater fishes.