Not related to saltwater or migratory eels, this South American fish has an elegantly minimal method of moving through water. This is mostly achieved by a parabolic wave generated through the long ventral fin. The tiny pectoral fins may steer. Most of the body is taken up by electricity generating tissue. An adult may produce a 500-watt charge. The digestive and reproductive organs are confined to a small area just behind the head. Exhibited at New York’s Central Park Zoo more than a century ago, it has long been a popular aquarium display.