HomeMarine aquarium fishAngelfish & butterflyfishDiagonal butterflyfish Diagonal butterflyfish (Chaetodon fasciatus) Scientific name: Chaetodon fasciatus Forssk?l, 1775 The Diagonal butterflyfish (Chaetodon fasciatus) is a marine fish of the family Chaetodontidae. Native range: Western Indian Ocean, known only from the Red Sea. Reported from the Gulf of Aden. BiologyCommonly found on reef flats. Usually solitary or in pairs in areas with rich coral growth. Monogamous. Feed mainly on coral polyps. Oviparous. Form pairs during breeding.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameChaetodon fasciatusFamilyChaetodontidae (Butterflyfishes)OrderPerciformes (Perch-like fish)ClassActinopterygii (Ray-finned fishes)Maximum length22.0Common length15.0Depth range2–25 m (7–82 ft)EnvironmentMarine; reef-associated; depth range 2 - 25 mClimateTropicalDistributionWestern Indian Ocean: known only from the Red Sea. Reported from the Gulf of Aden.Conservation status (IUCN)Least Concern (LC)Threat to humansHarmlessUsesAquarium: commercialResilienceHigh, minimum population doubling time less than 15 months (Preliminary K or Fecundity.) More angelfish & butterflyfishPajama cardinalfishSphaeramia nematopteraBicolor butterflyfishPrognathodes dichrousHooded butterflyfishChaetodon larvatusMarquesas butterflyfishChaetodon declivisEritrean butterflyfishChaetodon paucifasciatusBluecheek butterflyfishChaetodon semilarvatusSee all angelfish & butterflyfish SourcesTaxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.Last updated 27 September 2026