Old woman angelfish (Pomacanthus rhomboides)

Classification (WoRMS)

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

Accepted name: Pomacanthus rhomboides · Authority: (Gilchrist & Thompson, 1908) · Taxonomic status: accepted · AphiaID: 220000.

Synonyms and superseded combinations recorded for this taxon: Holacanthus rhomboides Gilchrist & Thompson, 1908.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=220000 (CC BY 4.0). Accessed 2026-09-25.

Biology and life history (FishBase)

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

Maximum length: 46 cm · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 36 of 100 · Fishery importance: commercial · Aquarium trade: commercial.

FishBase notes: Young occur singly and commonly found in tide pools. Adults are commonly seen in small groups in midwater or near the surface.

Source: FishBase species summary (SpecCode 25430) — https://www.fishbase.se/summary/Pomacanthus-rhomboides.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.

Distribution and occurrence records (GBIF)

217 georeferenced occurrence records for Pomacanthus rhomboides are published through GBIF from 5 countries or marine areas. The map above plots 28 distinct locations from a sample of 217 records, omitting 6 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: South Africa (194); Mozambique (20); Madagascar (1); Seychelles (1); Tanzania, United Republic of (1).

Marine regions with a valid WoRMS distribution record: Mozambican Exclusive Economic Zone; South Africa (country).

Source: GBIF Occurrence Search (taxonKey 2396398) — https://www.gbif.org/occurrence/search?taxon_key=2396398&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=220000 (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 Pomacanthus rhomboides (Gilchrist & Thompson, 1908) 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 165842) — https://www.iucnredlist.org/species/165842/0; GBIF IUCN Red List category endpoint (taxonKey 2396398) — https://api.gbif.org/v1/species/2396398/iucnRedListCategory. Accessed 2026-09-25.

Description and natural history (Wikipedia)

The old woman angelfish, as an adult it is possibly the least colourful of the genus Pomacanthus. The adults are bronze brown on the anterior two thirds of their bodies with the posterior third being pale bluish grey. The juveniles resemble the juveniles of other species in the genus and are, therefore, more colourful than the adults.

They are mainly black with thin, want blue and white lines. The dorsal fin contains 11-13 spines and 22-25 soft rays while the anal fin contains 3 spines and 21-23 soft rays. This species attains a maximum total length of 46 cm.

The old woman angelfish is found in the western Indian Ocean. It is found from Maputo Bay in Mozambique southwards along the coast of South Africa as far as Knysna in the Western Cape.

The old woman angelfish is found along shorelines and on rocky reefs at depths between 5 and 30 m. The juveniles are found in shallow tidal pools. The adults live in small groups close to the coast where they feed on algae and benthic invertebrates. They will occasionally swim near the surface to feed on plankton.

The old woman angelfish was first formally described in 1908 as Holacanthus rhomboides by the Scots ichthyologist John Dow Fisher Gilchrist (1866–1926) and his South African colleague William Wardlaw Thompson (died 1917) with the type locality given as KwaZulu-Natal. The species is placed by some authorities in the subgenus Acanthochaetodon,. The specific name of this species, rhomboides means "rhombus-like", possibly a reference to its deep, almost quadrangular body.

The old woman angelfish has a range which does not overlap with the main areas of Africa's coast where fish are collected for the aquarium trade and is subsequently extremely rare in that trade.

Source: Wikipedia: Old woman angelfish — https://en.wikipedia.org/wiki/Old_woman_angelfish (CC BY-SA 4.0). Accessed 2026-09-25.