White-face butterflyfish (Chaetodon mesoleucos)

Classification (WoRMS)

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

Accepted name: Chaetodon mesoleucos · Authority: Forsskål, 1775 · Taxonomic status: accepted · AphiaID: 218739.

Synonyms and superseded combinations recorded for this taxon: Chaetodon hadjan Bloch & Schneider, 1801; Chaetodon mesoleucor Forsskål, 1775; Chaetodon mesoleucus Forsskål, 1775.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=218739 (CC BY 4.0). Accessed 2026-09-25.

Biology and life history (FishBase)

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

Maximum length: 13 cm · Common length: 12 cm · Depth range: 5–20 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 10 of 100 · Aquarium trade: never/rarely.

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

Source: FishBase species summary (SpecCode 25428) — https://www.fishbase.se/summary/Chaetodon-mesoleucos.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.

Distribution and occurrence records (GBIF)

41 georeferenced occurrence records for Chaetodon mesoleucos are published through GBIF from 6 countries or marine areas. The map above plots 21 distinct locations from a sample of 41 records, omitting 2 inland records that carry an institution's coordinates rather than a collection site; it shows where the species has been observed and reported, not a modelled range.

Most records by country or area: Saudi Arabia (24); Djibouti (7); Egypt (6); Eritrea (2); Philippines (1); Sudan (1).

Marine regions with a valid WoRMS distribution record: Red Sea; Djiboutian Exclusive Economic Zone.

Source: GBIF Occurrence Search (taxonKey 2385318) — https://www.gbif.org/occurrence/search?taxon_key=2385318&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=218739 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-25.

Conservation status (IUCN Red List)

The IUCN Red List assesses Chaetodon mesoleucos Forsskål, 1775 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 165618) — https://www.iucnredlist.org/species/165618/0; GBIF IUCN Red List category endpoint (taxonKey 2385318) — https://api.gbif.org/v1/species/2385318/iucnRedListCategory. Accessed 2026-09-25.

Description and natural history (Wikipedia)

Chaetodon mesoleucos has a bluish white anterior part of the body with a vertical black band running through the eye. The rest of the body is pale grey in colour marked with numerous vertical black lines. The caudal fin is black with a white on the inner margin near the caudal peduncle. This species attains a maximum total length of 13 cm, although 12 cm is more common.

Chaetodon mesoleucos is found in the northwestern Indian Ocean. It occurs from the central Red Sea, into the Gulf of Aden and around Socotra.

Chaetodon mesoleucos occurs at depths between 1 and 25 m, inhabiting coral reefs where they occur in pairs. They are thought to feed mainly on coral polyps but will eat a variety of benthic invertebrates. Little is known about the biology of this species.

Chaetodon mesoleucos was first formally described in 1775 by the Swedish-speaking Finnish explorer, orientalist, naturalist Peter Forsskål (1732-1763), his description was published in 1775 by his companion on his expedition to Yemen, the orientalist and mathematician Carsten Niebuhr. The type locality was given as Al-Mukhā in Yemen. It belongs to the large subgenus Rabdophorus which might warrant recognition as a distinct genus.

Chaetodon mesoleucos is uncommon in the aquarium trade. However, it is not a difficult species to keep in captivity.

Source: Wikipedia: Chaetodon mesoleucos — https://en.wikipedia.org/wiki/Chaetodon_mesoleucos (CC BY-SA 4.0). Accessed 2026-09-25.