Powder Blue Tang

One of the most striking tangs on the reef, this fish wears its health on its skin: the brighter its blue, the better condition it is in.

Also known as: powderblue surgeonfish, powder blue surgeonfish, powderblue surgeon, painted surgeon, powder-blue surgeonfish, powder-blue tang

At a glance it looks like other blue reef tangs, but this species has a crisp white band running from the base of its pectoral fin to its throat, set against its black head. That white throat band is the mark to look for.

This tang has an oval, laterally flattened body. Its sides are blue, its head is black, and its dorsal fin and the base of its tail fin are yellow. Its mouth, throat, and anal and pelvic fins are white, while its pectoral fins are almost see-through with a yellow sheen. Like other surgeonfishes, it carries a sharp, blade-like spine at the base of its tail that it can raise as a weapon. Its colours do not change as it grows up.

Powder blue tangs live in shallow, clear coastal and island coral reefs in the Indian Ocean, usually on flat reef tops and along the upper parts of seaward slopes, down to about 25 metres.

This is a daytime feeder that grazes on algae growing on the reef surface. It is usually solitary and territorial, and can be aggressive toward other surgeonfish, though it will feed alongside others in loose groups when algae is plentiful. If threatened, it can slash with the sharp spine at the base of its tail.

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  Atlantic Blue Tang

  Acanthurus coeruleus

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  Brown surgeonfish

  Acanthurus nigrofuscus

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  Caribbean Ocean Surgeonfish

  Acanthurus tractus

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  Chocolate surgeonfish

  Acanthurus pyroferus

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  Convict Surgeonfish

  Acanthurus triostegus

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  Doctorfish

  Acanthurus chirurgus