Red-toothed triggerfish

The red-toothed triggerfish is the only member of its genus and one of the most familiar fish on current-swept Indo-Pacific reefs. It reaches about 50 cm, though most are around 30 cm, and it lives between 5 and 40 m. It is a deep blue to purple fish with red teeth, and it is one of the calmer triggerfishes, though older fish can become bold.

Also known as: blue triggerfish, redtooth triggerfish, red-toothed triggerfish, redtoothed triggerfish, red-toothed triggerfish, redtoothed filefish, triggerfish, red-toothed triggerfish, blue triggerfish, redfang triggerfish, redtoothed triggerfish, red toothed file fish, redtooth trigerfish, redtoothed triggerfish, red toothed triggerfish, black-bodied triggerfish, leubiem bintang

Go by shape rather than colour, because the colour shifts. Look for a dark, deep-bodied triggerfish with a lyre-shaped tail whose upper and lower tips trail out into long points, and for the steeply raised fronts of the second dorsal and anal fins. Pale blue lines edge the fins and tail. Up close, the red teeth show against the mouth even when it is closed. A dark school hanging in the current above a reef slope is the usual sight.

The body is dark blue to purplish blue overall, with a lighter blue head, bluish-green markings on the face and glowing pale blue edges along the fins and the two tail lobes. The tail is lyre-shaped, with the top and bottom tips drawn out into long streamers. The front part of the second dorsal fin on the back and the anal fin underneath rise steeply, so both look tall at the front. The mouth seems to be set in a grin, and the teeth are small, red and needle-sharp, with two in the upper jaw showing even when the mouth is shut. The pectoral fins, the paired fins behind the gill covers, are small. This fish can shift its colour between purple, blue and bluish-green with its mood, its feeding and the water it is in.

It lives across the tropical Indo-Pacific and the Red Sea, from the East African coast to the far islands of the central Pacific. Look for it in reef channels and along seaward reef slopes where the current runs strong. It also uses shallower coastal water. Young fish stay near isolated patches of rubble or crevices that offer a shelter hole of the right size.

This is a fish of moving water. It hangs in the current off the slope and drops into cracks and under rocks so the flow does not sweep it away. It usually gathers in groups, and often in large schools, to pick zooplankton, the tiny drifting animals, out of the passing water. It also eats sponges, crustaceans, algae, and the remains of squid and fish. Because the pectoral fins are small, it drives itself with the dorsal and anal fins, waving them like propellers, which makes it very nimble in the flow. It can make a grunting sound.

Fish pair off for breeding. They gather at mating grounds where the males hold territories and build nests for the eggs. The female tends the eggs, and both parents guard them until they hatch.

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  Black Triggerfish

  Melichthys niger

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  Boomerang triggerfish

  Sufflamen bursa

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  Clown triggerfish

  Balistoides conspicillum

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  Grey triggerfish

  Balistes capriscus

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  Orange-lined triggerfish

  Balistapus undulatus

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  Picasso Triggerfish

  Rhinecanthus aculeatus