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Moorish idol

life science Maturity 5-7 Next article →

The Moorish idol is a very special fish found in the ocean.

moorish-pennant-bannerfish
moorish-pennant-bannerfish

It belongs to a group called Zanclidae. This fish is the only living member of its family. This makes it a relict, which is a living thing left over from the past. Most of these fish live on reefs in the Indo-Pacific region. They like to stay in places like lagoons or clear coral reefs.

Moorish Idol, Koror, PW imported from iNaturalist photo 65345368
Moorish Idol, Koror, PW imported from iNaturalist photo 65345368

Their habitat is a very important part of how many fish live there.

This fish has a very unique shape and look. Its body is thin and shaped like a disc. It has a long snout that looks like a tube. The fish has a white body with two wide black stripes. It also has yellow patches on its snout and its back end. One of its most famous parts is a long dorsal fin. This fin has a long part that looks like a whip.

Moorish Idol, Koror, PW imported from iNaturalist photo 65345368
Moorish Idol, Koror, PW imported from iNaturalist photo 65345368

The fish also has small bony bumps over its eyes.

Scientists have studied this fish for a long time. Carl Linnaeus first described it in the year 1758. He called it Chaetodon cornutus in a book called Systema Naturae. Later, Georges Cuvier put it in a new group called Zanclus in 1831. In 1876, Pieter Bleeker named its family Zanclidae. The name Zanclus comes from a Greek word for a sickle. This name describes the curved shape of its long fin. The name cornutus means horned to describe the bumps on its eyes.

These fish have a very interesting way of growing. They start as tiny larvae that drift in the open ocean. In the preflexion stage, the babies have no fin spines. They grow more color as they get bigger. In the postflexion stage, they develop full fins and a kite shape.

Moorish Idol, Koror, PW imported from iNaturalist photo 65345368
Moorish Idol, Koror, PW imported from iNaturalist photo 65345368

They also start to look more like the thin adults. Most Moorish idols eat sponges for about 70% of their food. They also eat algae, coral polyps, and other small things.

In some places, the Moorish idol does something very brave. In Palau, hundreds of fish gather in large schools to spawn. Spawning is when they release eggs and sperm into the water. This happens in the winter between December and March. This event is very risky because many sharks wait to hunt them.

Moorish Idol, Koror, PW imported from iNaturalist photo 65345368
Moorish Idol, Koror, PW imported from iNaturalist photo 65345368

Grey reef sharks often attack the schools in the open water. Because so many fish are eaten, the event can seem very dangerous. You might even see this fish in movies like Finding Nemo.

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File:Moorish Idol, Koror, PW imported from iNaturalist photo 65345368.jpg
Moorish Idol, Koror, PW imported from...
File:moorish-pennant-bannerfish.jpg
moorish-pennant-bannerfish.jpg
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