A dark, deep-bodied grouper that reads as a black silhouette hanging in the mouth of a cave. Up to 60 cm (24 in), and shaped unlike any other grouper here - flattened side to side rather than round in section, which is what lets it work inside crevices and under ledges where the rest of the family cannot go.
The name is in the mouth. Open, the throat and mouth lining are bright orange-red, and a gaping fish looks briefly like a different animal. Whether the color signals anything is unknown; it is visible only at moments when the fish is yawning or feeding.
It hunts small fish, particularly the glassfish and cardinalfish that shoal inside caves, which is another reason for the shape: a predator that lives in the same cave as its prey needs to fit.
It is a common resident of wrecks throughout this sea, holding the same hold or corridor for years, and it will approach a diver closely enough to be uncomfortable for a fish that is nearly all mouth.
The genus. Aethaloperca Fowler 1904 - aethalos (sooty or black) + perca (perch). ETYFish
- uniformly dark brown to black fish, deep-bodied and strongly compressed
- inside of the mouth and throat bright orange-red, visible when it gapes
- pale margin along the rear of the tail, sometimes worn away
- length up to 60 cm
