Dark green, ruled with curved orange lines that run back from the snout across the whole body, with an orange band at the tail base. Up to 30 cm (12 in), and one of the more aggressive fish on the reef relative to its size.
It eats what other fish cannot. Urchins are turned over and attacked through the mouth on the underside, coral branches are bitten off, shelled molluscs are crushed, and the same jaw handles algae and worms. A triggerfish jaw is a set of eight heavy incisors on a short powerful skull, and it lets a fish this size make a living out of armored food.
Nesting is when it becomes a problem for divers. The female digs a crater in rubble, lays there, and defends a cone of water above it that widens toward the surface; she charges anything inside it and the bite takes chunks out of fins. Swimming upward keeps you in the cone. The way out is sideways, low, and unhurried.
Males and females are separable if you look at the snout: the orange lines cross it in females and fade out in adult males.
The genus. Balistapus Tilesius 1820 - a- (without) + pous (foot). ETYFish
The species. Balistapus undulatus (Park 1797) - wavy. ETYFish
- dark green body ruled with curved orange lines running back from the snout
- orange band across the base of the tail, and a yellow patch behind the mouth
- males lose the lines on the snout, females keep them
- length up to 30 cm
Why it's threatened
There are no known major threats.
Threat classification from the IUCN Red List.
