Blue-green and yellow with two blue lines across the snout and long trailing tail lobes. It turns urchins over to get at the underside.
To about 60 cm and commonly 30 to 45; sources differ. It lives to at least twenty-three years. This is one of the most strongly coloured triggerfish: greenish or bluish-grey on the back, orange-yellow on the lower head and belly, with two broad curved bright blue bands running across the face from the snout, below and around the eye. There are blue marks on the base of the tail and on the fins. Large adults grow long trailing filaments from the tail lobes and from the rear of the dorsal and anal fins.
The grey triggerfish overlaps in Florida and is drab olive-grey with pale mottling and no blue face bands.
It blows jets of water at sand to uncover food, and it flips sea urchins over to attack the soft underside — that behaviour is worth watching for. It makes a nest depression in sand and guards it hard: a nesting female will charge and bite a diver who enters the cone of water above the nest. It lives between about 3 and 30 m, and has been recorded far deeper.
It is listed as near threatened, and the global figure hides two different situations. Caribbean populations are broadly healthy, with protected spawning grounds in Puerto Rico and the US Virgin Islands. Brazilian and Gulf of Guinea populations have fallen by more than ninety per cent since the 1980s.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.