Eels - May be responsible for some sightings of lake monsters. Eels are fish of the order Anguilliformes. Depending on their species, they can reach between 10 cm. to 3 m., and weigh up to 65 kg. The number of rays of the gill webbing consists from 6 - 51, sometimes they are absent altogether. Their fins are always spineless. The back and anal fins are long, usually connecting with the tail fin. The belly and chest fins are absent. The shoulder girdle is separate from the skull. The scales are cycloid or absent. The flat and transparent larva of the eel is called a leptocephalus. A young eel is called an elver. Most eels prefer to dwell in shallow waters, hide at the bottom layer of the ocean, sometimes in holes. Only the Anguillidae family comes to fresh water to dwell there (not to breed). Some eels dwell in deep water. Most eels are predators. 固opFoto / Fortean