A butterflyfish with an elongated snout.
Its English name "longnose" also describes this beak-like snout. The scientific name rostratus means "beaked."
The English name "copperband" refers to the copper-colored bands on the body.
It is also called "Chelmo" after its genus name, Chelmon. The genus contains only three species: this fish, the margined coralfish, and the Mueller's coralfish.
