The electric eel, Electrophorus electricus, is a species of fish. It can weigh up to six pounds. It can give electric shocks of up to six hundred fifty watts of electricity. The animal uses these shocks both for hunting and to defend itself. It lives in the stagnant muddy river bottoms of the Orinoco and the Amazon, and uses low-voltage electric fields to find its prey.
The electric eel is an apex predator in the parts of South America where it lives. This means it usually has no enemies except other animals of its own species. It can kill animals larger than itself. Its electric organs evolved from muscles, and make up four fifths of its body.
Despite its name, the electric eel is not an eel. It is a knifefish. It is an obligatory air breather (must breath air). This makes sense, because the muddy water is very low in oxygen, and it needs oxygen to power its electric organs.
Because they can shock, very few of these fish are kept as pets. But if the eel repeatedly shocks, its electric organs become completely discharged. Then a person can touch it without being shocked.
- Froese, Rainer and Pauly, Daniel, eds. (2005). "Electrophorus electricus" in FishBase. 
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