Gulper

Any of nine species of deep-sea fish constituting three families, placed by some authorities in the order Anguilliformes (eels) and by others in a distinct order, Saccopharyngiformes (or Lyomeri). Gulpers range to depths of 2,700 m (9,000 feet) or more. The members of one family, Monognathidae, have mouths of normal proportions, but the other gulpers (Eurypharyngidae and Saccopharyngidae)