The scientific study of fishes of the Great Lakes of Nicaragua began in 1864 with the description by Gunther of Heros labiatus (=Cichlasoma labiatum) from Lake Managua. Subsequently, Gunther reported on several other species collected in the Great Lakes by Captain J. M. Dow. Astorqui (1967) reviewed the sparse ichthyological literature dealing with Nicaraguan fishes and pointed out the paucity of recent studies. Since then Villa (1971) has produced a provisional list of the freshwater and brackish water fishes of Nicaragua and Astorqui (1972) has analyzed the ichthyofauna of the Great Lakes Basin. Riedel (1972) discussed the geological history of the Great Lakes in relation to the composition and evolution of its fish fauna