Fish
Cusk Eel
Ophidiidae · also called cusk eels
Once holding the record for the deepest fish ever recovered from the ocean floor, a cusk eel spans one of the widest depth ranges of any fish family, with relatives living everywhere from shallow coral reefs to the crushing pressure of ocean trenches.
Overview
The cusk eel, family Ophidiidae, is an elongated, eel-like fish native to ocean habitat spanning shallow reefs to extreme hadal depth across every major ocean basin in the world. Its former deep-sea depth record, remarkable range of habitat adaptations, and considerable species diversity make it one of the more ecologically versatile fish families found anywhere in the ocean.
A family that spans nearly the whole ocean
Few fish families cover as much vertical territory as the cusk eel, whose different species have adapted to conditions ranging from sunlit coral reefs to some of the most crushing pressures found anywhere on the planet.
Status
Least Concern, remaining widespread across its broad range of ocean habitat worldwide.
Cusk Eel: common questions
Did a cusk eel really hold the record for deepest fish ever found?
Yes, a member of this family was recovered from one of the deepest points ever sampled in the ocean, holding the record for the deepest fish collection for decades before being surpassed by more recent hadal-zone discoveries.
How deep can cusk eels live?
This family spans an unusually wide depth range, with different species found from shallow coastal reefs down to the deepest ocean trenches, a broader vertical range than most fish families cover.
Are all cusk eels found in the deep sea?
No, while some species live at extreme depth, this family also includes species found in much shallower coastal and reef habitat, reflecting its unusually wide range of depth adaptations.
Do cusk eels glow in the dark?
A number of species within this family are capable of producing their own light, an adaptation used by those living in the darker portions of the family's broad depth range.