The longfin snake-eel (''Pisodonophis cancrivorus'') is an

eel Eels are ray-finned fish belonging to the order Anguilliformes (), which consists of eight suborders, 19 families, 111 genera, and about 800 species. Eels undergo considerable development from the early larval stage to the eventual adult stage ...

in the family Ophichthidae (worm/snake eels).''Pisodonophis cancrivorus''
at www.fishbase.org. It was described by John Richardson in 1848.

References

Ophichthidae Fish described in 1848 {{Ophichthidae-stub