Electrophorus voltai, one of the two newly discovered electric eel species, lives in the Brazilian highlands. (Credit: L. Sousa)

In the murky freshwater rivers and streams that snake across the Amazon lurks an eight-foot fascination: the electric eel. Since their discovery more than 250 years ago by Swedish naturalist Carl Linnaeus, researchers have thought the electric eel was a one-of-a-kind phenomenon, with only one species, Electrophorus electricus.

Now scientists say they have discov