Cyematidae - The bobtail snipe eels are two species of deep-sea fishes in the family Cyematidae, one only in each of two genera.

Eurypharyngidae - The pelican eel's most notable feature is its enormous mouth, much larger than its body.


Monognathidae - Monognathus is the only genus of the family Monognathidae of deep sea eel-like fishes.

Saccopharyngidae - Saccopharynx is a genus of deep sea eel-like fishes with large mouths, distensible stomachs and long scaleless bodies.