HomeMarine aquarium fishAngelfish & butterflyfishBlackback butterflyfish Blackback butterflyfish (Chaetodon melannotus) Scientific name: Chaetodon melannotus Bloch & Schneider, 1801 The Blackback butterflyfish (Chaetodon melannotus) is a marine fish of the family Chaetodontidae. Native range: Indo-Pacific, Red Sea and East Africa to Samoa, north to southern Japan, south to Lord Howe Island. Throughout Micronesia. BiologyDorsal spines (total): 12 - 13; Dorsal soft rays (total): 18-21; Anal spines: 3; Anal soft rays: 16 - 18. Changes color when frightened or when observed at night. The dorsal portion of the body turns black except for two white patches.Source: FishBase, licensed CC BY-NC 4.0. Species factsScientific nameChaetodon melannotusFamilyChaetodontidae (Butterflyfishes)OrderPerciformes (Perch-like fish)ClassActinopterygii (Ray-finned fishes)Maximum length18.0Depth range4–20 m (13–66 ft)EnvironmentMarine; reef-associated; non-migratory; depth range 4 - 20 mClimateTropicalDistributionIndo-Pacific: Red Sea and East Africa to Samoa, north to southern Japan, south to Lord Howe Island. Throughout Micronesia.Conservation status (IUCN)Least Concern (LC)Threat to humansHarmlessUsesAquarium: commercialResilienceLow, minimum population doubling time 4.5 - 14 years (K = 0.14, tmax = 20) More angelfish & butterflyfishPajama cardinalfishSphaeramia nematopteraAtoll butterflyfishChaetodon mertensiiRaccoon butterflyfishChaetodon lunulaScrawled butterflyfishChaetodon meyeriSpot-tail butterflyfishChaetodon ocellicaudusLined butterflyfishChaetodon lineolatusSee 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