Largest gulper eels

Gulper eels are bizarre-looking deep-sea eel-like fish with disproportionately large mouths, which live in the deep sea, and constitute a taxonomic order, Saccopharyngiformes distinct from but closely related to true eels, Anguilliformes. The largest species are the swallowers, which belong to the genus Saccopharynx, and are known to measure up to 2 m long, although much of this consists of their exceedingly long, attenuated tail. Ten species of swallower are currently recognized but most are poorly known, represented by few specimens, so there could well be longer specimens and additional species yet to be recorded.

Perhaps the most famous gulper eel is the pelican eel Eupharynx pelecanoides, named after its proportionately enormous, pelican-like mouth, which is approximately a quarter of this fish's entire length (and greater than half its pre-anal length), and highly stretchable, thereby enabling the pelican eel to swallow fishes even bigger than itself.

This species attains a known total length of around 75 cm, and has been recorded from temperate and tropical regions of all oceans.