This fish eats coral and nothing else, and it eats it a few polyps at a time. It takes bite after bite, many of them in a few minutes, keeps it up through the daylight hours, and spreads the work across many colonies so that no single coral head is stripped. A morning of this fish's feeding is several thousand small wounds on the reef, none of them fatal.
That diet is a trap. A strict coral feeder cannot be switched to anything else, which is why these fish die in aquariums no matter what is put in front of them, and why counts of them are used as a measure of reef condition. Where the coral goes, they go, and they go fast.
They are also picky within their one food. In the northern 🌊 Red Sea they take mainly Acropora, Pocillopora, Montipora and Stylophora, prefer big colonies to small ones, and avoid heads that already have coral gobies living in the branches. Those little gobies carry a bitter toxin in their skin, and a butterflyfish that has once bitten into a branch with one in it does not come back.
The body is orange-yellow with about fourteen fine dark stripes, a dark band across the head and through the eye, a black chin, and a black tail and anal fin that are both rimmed in bright yellow. That rim matters: the Arabian butterflyfish of the 🌊 Gulf of Oman and the 🌊 Persian Gulf has the same shape and the same black fins, but without the yellow edge.
This species belongs to the 🌊 Red Sea and the 🌊 Gulf of Aden and is found nowhere else in the world. It lives shallow, mostly in the top 15 m, in pairs that hold a feeding territory and stay together year-round, and it releases its eggs into open water at dusk with no further care.
The genus. Chaetodon Linnaeus 1758 - chaeto- (bristle) + odon (tooth). ETYFish
- orange-yellow body with about fourteen fine dark stripes
- black tail and black anal fin, both rimmed with yellow
- dark band through the eye, black chin and lips
- always over living stony coral, nearly always in a pair
- up to 14 cm
Why it's threatened
Threat classification from the IUCN Red List.
