Gymnotiformes

Order of bony fishes

The Gymnotiformes are an order of teleost bony fishes commonly known as Neotropical knifefish or South American knifefish, which inhabit fresh water (the only exceptions are species that occasionally may visit brackish water to feed). These mostly nocturnal fish have long bodies and swim using undulations of their elongated anal fin. They are electric fish, are capable of producing electric fields for various purposes, such as detecting prey, for navigation, communication, and, in the case of the electric eels (Electrophorus spp.), attack and defense.

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