Bleeker's parrotfish

Bleeker's parrotfish is a medium-sized grazer of clear central Indo-Pacific reefs, reaching 49 cm. It scrapes fine algae off coral rubble and bare reef rock with its beak. The sexes look so different that they are easy to take for two fish: females are dark and barred, males are green and pink. Females feed in small groups, often mixed in with other species, while a male tends to keep to himself nearby.

Other green parrotfish share these reefs, so look at the side of the male's face. He carries a large, squared-off cream patch below the eye, ringed all the way round by a thick green line, like a window with a painted frame. Nothing else on the fish is that pale. On a dark barred female, the plain pale tail and tail base against the dark body is the thing to check instead.

Males are greenish, with pink edges to the scales that give the body a fine net-like pattern. The tail has a green centre and green outer edges. Females and other early-phase fish are dark brown, broken by three or four broad pale bars down the sides, with a pale tail and pale tail base. In both, the fused tooth plates are fully exposed, since the lips do not cover them. The tail is cut straight across.

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  Bicolour parrotfish

  Cetoscarus bicolor

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  Blue-barred parrotfish

  Scarus ghobban

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  Bridled parrotfish

  Scarus frenatus

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  Carolines parrotfish

  Calotomus carolinus

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  Chameleon Parrotfish

  Scarus chameleon

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  Common parrotfish

  Scarus psittacus