Spiny eel

The name spiny eel is used to describe members of two different families of fish: the freshwater Mastacembelidae of Asia and Africa, and the marine (and generally deep sea) Notacanthidae. Both are so-named because of their eel-like shape and sturdy fin spines. These two families are not related and that the Notacanthiformes belong to the Superorder Elopimorpha, of which members are characterized by having a leptocephalus larvae. The freshwater Mastacembelids do not share this characteristic and are popular specimens in the aquarium trade.