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Moorish idol

Zanclus cornutus

Description: Moorish idols (Zanclus cornutus) have vertically compressed, disk-like bodies with bars of black, white and yellow. The bars of color may serve as “disruptive coloration” that breaks up the body outline, making it difficult for predators to tell where the fish begins and ends. The fins are small, except for the dorsal fin whose spines are elongated to form a trailing, sickle-shaped, white whip-like extension; these spines shorten with age. They have a small extending mouth with long bristle-like teeth at the end of a long, tubular snout. The snout has a yellow saddle-like area on top. They have horn-like projections over the eyes.

Size: Adults usually reach a length of seven inches (18 cm) however, some have been reported reaching lengths of 9.1 inches (23 cm).

Behavior: Moorish idols are diurnal (active during the day), spending nights on the bottom of the reef. They form pairs who mate for life and the male will display aggression to protect its mate. Usually found alone or in pairs, but beautiful schools can be seen, particularly at the juvenile state.

Diet: Their diet consists of corals, sponges, tunicates and other benthic invertebrates. They perpetually forage for food.

Reproduction: Moorish idols are pelagic spawners, they release eggs and sperm in the water column. The fertilized eggs then drift away with the currents.

Habitat/range: They prefer flat reefs in both murky and clear water. The Moorish idol is one of the most widespread fish, it can be found throughout the Indian Ocean, Red Sea and all of the tropical Pacific.

Status: Not evaluated.