Marcusenius thomasi is a species of ray-finned fish in the family Mormyridae. It is found in Guinea, Guinea-Bassau, Liberia, and Sierre Leone. Its natural habitats are rivers, intermittent rivers, and freshwater lakes. It is threatened by Mining and deforestation.
The fish is named in honor of anthropologist Northcote W. Thomas (1868-1936), who collected the type specimen.[1]