Oman butterflyfish (Chaetodon dialeucos)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Acanthuriformes · Family: Chaetodontidae · Genus: Chaetodon.

Accepted name: Chaetodon dialeucos · Authority: Salm & Mee, 1989 · Taxonomic status: accepted · AphiaID: 273334.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=273334 (CC BY 4.0). Accessed 2026-09-25.

Biology and life history (FishBase)

Measured values published by FishBase for Chaetodon dialeucos. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.

Maximum length: 18 cm · Depth range: 1–10 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 10 of 100 · Aquarium trade: never/rarely.

FishBase notes: Inhabit rocky and coral reefs (Ref. 9710). Oviparous (Ref. 205). Form pairs during breeding (Ref. 205).

Source: FishBase species summary (SpecCode 25436) — https://www.fishbase.se/summary/Chaetodon-dialeucos.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.

Conservation status (IUCN Red List)

The IUCN Red List assesses Chaetodon dialeucos Salm & Mee, 1989 as Least Concern (code LC). No trend, population estimate or threat analysis is given here, because none is available from this source without the Red List API; follow the source link for the full assessment, including its date.

Source: IUCN Red List of Threatened Species (taxon 165726) — https://www.iucnredlist.org/species/165726/0; GBIF IUCN Red List category endpoint (taxonKey 2385447) — https://api.gbif.org/v1/species/2385447/iucnRedListCategory. Accessed 2026-09-25.

Description and natural history (Wikipedia)

The Oman butterflyfish is a rather drab butterflyfish which has a greyish coloured body with the margins of the scales being dark brown. There is a broad, vertical white bar to the rear of the head and the mouth is white. The caudal fin is black which is slightly rounded.

The dorsal fin contains 12 spines and 21-22 soft rays while the anal fin has 3 spines and 19 soft rays. This species grows to a maximum total length of 18 cm. Juveniles have a sharply defined white stripe to the rear of the eye and a white caudal fin.

The Oman butterflyfish is found in the northwestern Indian Ocean in the Arabian Sea along the southern coast of the Arabian Peninsula in Yemen and Oman.

The Oman butterflyfish lives in rocky and coral reefs as well as on patches of coral on sloping seabeds made up is sand at depths of 5 to 25 m. Its diet is made up is coral polyps, sea anemones, worms, crustaceans, and algae. It is an oviparous species which forms pairs for spawning.

The Oman butterflyfish was first formally described in 1989 by Rodney V. Salm and Kevin Mee with the type locality given as southwest of Barr al Hikman in the Sultanate of Oman. Some authorities place this species within the large subgenus Rabdophorus but others consider it to be incertae sedis.

Source: Wikipedia: Oman butterflyfish — https://en.wikipedia.org/wiki/Oman_butterflyfish (CC BY-SA 4.0). Accessed 2026-09-25.