Africa: native in all the basins of the Sahelo-Sudanese region, the Senegal, Gambia, Corubal, Volta, Ouémé, Niger, Bénoue, Chad and Nile basins and Lake Turkana (Ref. 2920, Ref. 3012, Ref. 3514). Successful introductions in the storage reservoirs of Côte d'Ivoire, the Cross, Sanaga, Nyong and Ogowe rivers and the lower and middle Congo basin, including Ubangui and Kasaï (Ref. 2920); rapidly enlarged its distribution in the Lualaba (upper Congo basin) after extraordinary inundations in 1979 (Ref. 51906). Also introduced in Madagascar (Ref. 13333). Several countries report adverse ecological impact after introduction. |