(subclass Actinopterygii, order Mormyriformes)
A monotypic family that comprises the freshwater fish Gymnarchus niloticus. It has an eel-like body, small eyes, a very long dorsal fin, and pectoral fins; the pelvic and anal fins are absent. This fish grows to a length of at least 1.2 m, and can produce low-voltage electric currents using modified muscles in the tail region. It is found in tropical Africa.
Subjects: Zoology and Animal Sciences.