Mormyrinae
Petrocephalinae
The family Mormyridae, sometimes called "elephantfish" (more properly freshwater elephantfish), are freshwater fish in the order Osteoglossiformes native to Africa. It is by far the largest family in the order with around 200 species. Members of the family are popular, if challenging, aquarium species. These fish are also known for having large brain size and unusually high intelligence.
They are not to be confused with the Australian ghost shark (Callorhinchus milii) which is sometimes referred to as the "elephantfish", but is better known as the elephant shark in the scientific community.
Read more about Mormyridae: Description and Biology, Classification