Swamp eels are members of the Synbranchidae family. They are distributed in Asia, Indo-Australian Archipelago, West Africa, Mexico, Central and South America. They are recognized by having a snake like appearance with no pectoral and pelvic fins, rudimentary dorsal, anal and caudal fins, small eyes, and small gill opening.
Swamp eels are primarily freshwater fish with some species found in brackish water. They are capable of surviving short periods out of water. Most of them are bottom burrowers or cave dwellers. They are mostly nocturnal predators that eat a variety of animals including crayfish, shrimp, worms, frogs, tadpoles, and other fishes.
There are 4 genera and 23 species worldwide.