A heavy gray triggerfish with yellow-edged fins and a netted pattern over the back, up to 60 cm (24 in). Out of season it is a slow, unremarkable fish blowing at sand. In season it is the reason divers here learn triggerfish geometry.
The female digs a crater up to a meter across in rubble, lays in it, and defends a cone of water above it that widens toward the surface. She charges anything inside that cone, and at this size the bite takes chunks out of fins and skin. Swimming up means staying inside the cone all the way to the surface; the way out is horizontal and low, keeping the fish in sight.
Feeding is excavation. It shifts stones with its teeth and blows water at the bottom to expose urchins, molluscs and crustaceans, and it will pull apart branching coral to get at what is inside. Other fish follow it for the leftovers.
Everything about the family is built around one lock: the first dorsal spine raises and is held by a smaller spine behind it, so a fish wedged into a hole cannot be pulled out.
The genus. Pseudobalistes Bleeker 1865 - pseudo- (false). ETYFish
The species. Pseudobalistes flavimarginatus (Rüppell 1829 - flavus (yellow) + marginatus (edged or bordered). ETYFish
- heavy gray-brown body with yellow edges to the fins and a yellow band across the cheek
- pale scale outlines giving a netted look over the back
- digs a broad crater in sand and hangs above it
- length up to 60 cm
Why it's threatened
There are no known major threats.
Threat classification from the IUCN Red List.
