Geography of Africa outer ranges. The main drainage of the continent is to the north and west, or towards the basin of the Atlantic Ocean. To the main African rivers belong: Nile (the longest river of Africa), Congo (river with the highest water discharge on the continent) and the Niger, which flows half of its length through the arid areas. The largest lakes are the following: Lake Victoria (Lake Ukerewe), Lake Chad, in the centre of the continent, Lake Tanganyika, lying between the Democratic Republic of Congo, Burundi, Tanzania and Zambia. There is also the considerably large Lake Malawi stretching along the eastern
Nile tilapia to this species, too. An undescribed population found at, for example, Wami River, Lake Manyara, and Tingaylanda seems to be a close relative. Nile tilapia The Nile tilapia ("Oreochromis niloticus") is a species of tilapia, a cichlid fish native to Africa from Egypt south to east and central Africa, and as far west as Gambia. It is also native to Israel, and numerous introduced populations exist outside its natural range (e.g., Brazil). It is also commercially known as mango fish, "nilotica", or "boulti". The first name leads to easy confusion with another tilapia traded commercially, the mango tilapia ("Sarotherodon galilaeus").