The subfamily Mormyrinae contains all but one of the genera of the African freshwater fish family Mormyridae in the order Osteoglossiformes. They are often called elephantfish due to a long protrusion below their mouths used to detect buried invertebrates that is suggestive of a tusk or trunk (some such as Marcusenius senegalensis gracilis are sometimes called Trunkfish though this term is usually associated with an unrelated group of fish). They can also be called tapirfish. Mormyrinae is the largest subfamily in the Osteoglossiformes order with around 170 species.