- The European Eel (Anguilla anguilla)
- fascinating life cycle including transparent-bodied juvenile stages
- nocturnal like most eels
- swims by generating waves which travel the length of its body
- swims backwards by reversing the direction of the wave
- life-span in the wild unconfirmed by scientists
- captive specimens live for over 80 years
- one specimen, "the Brantevik eel" or "Ale the eel", lived for 155 years in the well of a Swedish family
- can reach 1.5m (4 ft 11 in) in length
- Conservation Status: CRITICALLY ENDANGERED