The heaviest moray in the sea: up to 3 m (10 ft) and 30 kg (66 lb), brown with black leopard blotches that crowd together behind the head. By day only the head shows, jaws working - not a threat display but breathing, since a moray has no gill covers to pump water and must open its mouth to move it.
It hunts with groupers, and the arrangement was worked out here. A grouper that has chased prey into a crevice swims to a resting moray and shakes its head rapidly in front of it; the moray follows it back to the hole and goes in. Whatever tries to escape into the reef is taken by the eel, and whatever bolts into open water is taken by the grouper. The signal is a genuine invitation, the grouper can indicate the hiding place by pointing its body at it, and the two hunt together more successfully than either does alone. It is one of very few cases of coordinated hunting between species that are not related.
The second set of jaws is real. Inside the throat sits a mobile pharyngeal jaw that shoots forward into the mouth to grip prey and drag it back - the only vertebrate known to move food this way, and the reason an eel with no ability to suck can swallow something large.
Bites happen when a hand goes into a hole or when someone feeds them. The teeth are backward-curved and the animal cannot let go quickly, which is why a moray bite is a tearing wound rather than a puncture. The flesh carries ciguatera and should never be eaten.
The genus. Gymnothorax Bloch 1795 - gymnós (bare or naked) + thṓrax (breast or chest). ETYFish
- massive brown eel with black leopard blotches, densest behind the head
- head held out of a hole with the mouth opening and closing
- no pectoral fins, no gill covers, just a round gill opening behind the head
- length up to 3 m
Why it's threatened
There are no major threats known to affect this species.
Threat classification from the IUCN Red List.
