Moorish Idol

Moorish Idol
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Perciformes Family: Zanclidae Genus: Zanclus Species: Z. cornutus
Binomial name
Zanclus cornutus (Linnaeus, 1758)

The Moorish Idol (Zanclus cornutus) is a small perciform marine fish, the sole representative of the family Zanclidae (from the Greek zagkios, "oblique"). A common inhabitant of tropical to subtropical reefs and lagoons, the Moorish Idol is notable for its wide distribution throughout the Indo-Pacific. A number of butterflyfishes (all of the genus Heniochus) closely resemble the Moorish Idol.

It is said the Moorish Idol got its name from the Moors of Africa, who purportedly believe the fish to be a bringer of happiness. Moorish Idols are also popular aquarium fish, especially since the release of the film Finding Nemo, which featured a Moorish Idol named Gill (voiced by Willem Dafoe) as one of Nemo's tankmates. Despite their popularity, Moorish Idols are notorious for their short aquarium lifespans and difficulty.

Contents

1 Physical description 2 Habitat and diet 3 Behaviour and reproduction 4 Pop culture 5 Aquarium life 6 See also 7 External link

Physical description

With distinctively compressed and disk-like bodies, Moorish Idols stand out in contrasting bands of black, white and yellow. The fish have relatively small fins, except for the dorsal fin whose 6-7 spines are dramatically elongated to form a trailing, sickle-shaped crest. Moorish Idols have small terminal mouths at the end of long, tubular snouts; many long bristle-like teeth line the mouth.

The eyes are set high on the fish's deeply keeled bodies; in adults, perceptible bumps are located above each. The anal fin may have 2-3 spines. Moorish Idols reach a maximum length of 23 centimetres. The sickle-like dorsal spines actually shorten with age.

Habitat and diet

Generally denizens of shallow waters, Moorish Idols prefer flat reefs. The fish may be found at depths from 3 to 180 metres, in both murky and clear conditions. The range of the Moorish Idol includes East Africa and the Ducie Islands; Hawaii, southern Japan and all of Micronesia; they are also found from the southern Gulf of California south to Peru.

Sponges, tunicates and other benthic invertebrates constitute the bulk of the Moorish Idol's diet.

Behaviour and reproduction

Often glimpsed alone, Moorish Idols will also form pairs or occasionally small schools. They are diurnal fish, sticking to the bottom of the reef at night and adopting a drab coloration. Like the butterflyfish, Moorish Idols mate for life; as juveniles, they are more apt to school. Adult males tend to be aggressive toward one another.

Moorish Idols are pelagic spawners; that is, eggs and sperm are released in midwater and the fertilized eggs are left to drift away with the currents. The impressive range of these fish may be explained by the unusually long larval stage; the fish reach a length of 7.5 centimetres before becoming free-swimming juveniles. Before this time the developing larvae will have drifted considerable distances.

Pop culture

In the 2003 Pixar film Finding Nemo, a Moorish Idol (voiced by Willem Dafoe) was one of Nemo's tank inhabitants.

Moorish Idols have long been among the most iconic of coral reef fauna. They have graced all types of underwater-themed products, such as shower curtains, blankets, towels, and wallpaper.

Aquarium life

The Moorish Idols are notorious for their aquarium-keeping difficulty. These fish require enormous tanks, often exceeding 200 U.S. gal. They are also voracious eaters, and are infamous for becoming incredibly destructive. Their captive survival rate is very low: most do not survive for a full year. Most that live past this mark typically die shortly thereafter. To avoid these shortfalls, some aquarists prefer to keep substitute species that look very similar to the Moorish Idol. These substitues are all butterflyfishes of the genus Heniochus, and include the Pennant Coralfish (Heniochus acuminatus); Threeband Pennantfish (H. chrysostomus), and the False Moorish Idol (H. diphreutes).

See also

• List of fish common names
• List of fish families

External link

• FishBase entry on Zanclus cornutus (http://ichtyonb1.mnhn.fr/Summary/SpeciesSummary.cfm?ID=5950&genusname=Zanclus&speciesname=cornutus)