True eels are found globally in a vast range of aquatic environments:

: Most species have a snakelike appearance with a complete absence of pelvic fins . Their dorsal, anal, and caudal fins are often continuous, forming a single fringe around the tail.

: The family Anguillidae includes catadromous species that live in freshwater but migrate to the ocean to spawn. Major Groups : Well-known families include: Muraenidae : Moray eels. Congridae : Conger and garden eels. Anguillidae : Freshwater eels. Ophichthidae : Snake and worm eels. Life Cycle