Rock beauty (Holacanthus tricolor)
Source-cited species reference: taxonomy from WoRMS, biology from FishBase, occurrence map from GBIF, conservation from IUCN Red List, description from Wikipedia.
Last updated
Diego Delso · via Wikipedia: Rock beauty · CC BY-SA 4.0
The rock beauty (Holacanthus tricolor), also known as corn sugar, coshubba, rock beasty, catalineta or yellow nanny, is a species of marine ray-finned fish in the angelfish family Pomacanthidae. It is found in the western Atlantic Ocean.
Scientific classification
- KingdomAnimalia
- PhylumChordata
- ClassActinopterygii
- DivisionTeleostei
- OrderAcanthuriformes
- FamilyPomacanthidae
- GenusHolacanthus
- SpeciesHolacanthus tricolor
Named by (Bloch, 1795)
Close relatives
Other species of Holacanthus with a Codexery entry.
- Queen angelfish Holacanthus ciliaris
Sources: Wikipedia taxobox: Rock beauty (CC BY-SA 4.0) · order, family and genus agree with WoRMS AphiaID 276017 (CC BY 4.0)
Conservation status
Least Concern (LC)
- LC▲ this species
- NT
- VU
- EN
- CR
- EW
- EX
Source: IUCN Red List assessment · GBIF copy of the Red List category
How big is it?
Largest length in the source, 0.35 m, next to a 1.8 m person.
Diagram: drawn by Codexery, schematic shapes to scale (not a likeness). Length: FishBase species summary
Where the rock beauty (holacanthus tricolor) has been recorded
Each dot is a place where the species has been observed and reported (38,524 records, half-degree grid) — not a modelled range. 7 inland records left out (institution coordinates). 3 isolated far-off records not drawn.
Map: drawn by Codexery. Data: GBIF occurrence search (records CC0 / CC BY) · Natural Earth basemap (public domain) · place coordinates: Wikipedia (CC BY-SA 4.0)
Classification (WoRMS)
Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Acanthuriformes · Family: Pomacanthidae · Genus: Holacanthus.
Accepted name: Holacanthus tricolor · Authority: (Bloch, 1795) · Taxonomic status: accepted · AphiaID: 276017.
Synonyms and superseded combinations recorded for this taxon: Chaetodon tricolor Bloch, 1795; Holocanthus tricolor (Bloch, 1795); Pomacanthus tricolor (Bloch, 1795).
Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=276017 (CC BY 4.0). Accessed 2026-09-25.
Biology and life history (FishBase)
Measured values published by FishBase for Holacanthus tricolor. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.
Maximum length: 35 cm · Common length: 30 cm · Depth range: 3–92 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 25 of 100 · Fishery importance: minor commercial · Aquarium trade: commercial.
FishBase notes: Inhabits rock jetties, rocky reefs and rich coral areas. Juveniles often associated with fire corals (Ref. 9710). Feeds on tunicates, sponges, zoantharians and algae. Marketed fresh (Ref. 3797).
Source: FishBase species summary (SpecCode 3610) — https://www.fishbase.se/summary/Holacanthus-tricolor.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.
Distribution and occurrence records (GBIF)
38,524 georeferenced occurrence records for Holacanthus tricolor are published through GBIF from 43 countries or marine areas. The map above plots 106 distinct locations from a sample of 3,000 records, omitting 10 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: United States of America (24,853); Puerto Rico (8,774); Brazil (1,447); Virgin Islands (U.S.) (846); Colombia (749).
The full country table, WoRMS marine regions and the sampling notes are on this species' Distribution page.
Source: GBIF Occurrence Search (taxonKey 5211450) — https://www.gbif.org/occurrence/search?taxon_key=5211450&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=276017 (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 Holacanthus tricolor (Bloch, 1795) 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 165879) — https://www.iucnredlist.org/species/165879/0; GBIF IUCN Red List category endpoint (taxonKey 5211450) — https://api.gbif.org/v1/species/5211450/iucnRedListCategory. Accessed 2026-09-25.
Description and natural history (Wikipedia)
The generic name Holacanthus comes from Ancient Greek ὅλος (hólos), meaning "full", and ἄκανθα (ákantha), meaning "spine"; the allusion was not explained by Lacépède, who erected the genus in 1802. The specific name tricolor means "three-colored" in Latin, and refers to the fact that adult rock beauties are predominantly yellow, black and red (the red coloration is, however, not prominent, as it only appears on some fins and the operculum margin of certain specimens).
Taxonomy
The rock beauty was first formally described in 1795 as Chaetodon tricolor by the German physician and naturalist Marcus Elieser Bloch (1723–1799) with the type locality given as Brazil. When Lacépède erected the genus Holacanthus, he moved Chaetodon tricolor to this new genus; in was then designated as the type species of Holacanthus by Desmarest in 1856. Some authorities split Holacanthus into two subgenera; this classification places the rock beauty alone in the subgenus Holacanthus and all other species in the subgenus Angelichthys (which was once an independent genus).
Body shape and size
The rock beauty has a deep, oval and strongly compressed body, and attains a maximum total length of 30 cm. It has a short snout, ending in a small mouth equipped with bristle-like teeth. The preoperculum has a large spine at its angle, and its vertical edge is serrated. The bone lying between the preoperclum and the operculum also has 1–4 large spines.
Coloration
Juveniles are yellowish on their body and fins, with a blue-margined black spot on the upper posterior part of the body. As they mature, the spot grows, eventually covering most of the body, the lower part of the dorsal fin and the upper part of the anal fin.
The head and the anterior quarter of the body remain yellow, as do the pectoral, pelvic and caudal fins. The mouth is purple, and the distal edge of the anal fin and the operculum margin are red (or orange). The upper and lower portions of the iris are both vividly blue.
Meristics
In the dorsal fin of a rock beauty there are 14 spines and 17–19 soft rays, while the anal fin has 3 spines and 18–20 soft rays.
The rock beauty is found in the western Atlantic, where it ranges from Bermuda and the waters off Georgia and Florida through the Caribbean Sea and the coasts of South America to as south as Rio de Janeiro. It is uncommon and localized in the Gulf of Mexico, where it only occurs at the Flower Gardens Banks National Marine Sanctuary off Texas and off Veracruz and on the Campeche Bank in Mexico.
The rock beauty is found at depths between 3-92 m. Adults occur around jetties, rocky reefs and coral reefs, while juveniles are often seen in areas of fire coral.
Adult rock beauties feed largely on sponges but will also eat corals, zoantharians, bryozoans, gorgonians, tunicates and algae. It is also thought that they consume the mucus secreted by other fish.
Adult rock beauties are normally encountered as pairs and appear to form long-term monogamous pairs. These pairs frequently consist of a larger individual and a smaller one, possibly indicating sexual dimorphism, although there is no sexual dichromatism. During mating, the pair ascends in the water column with their abdomens close together as they release eggs and milt into the water. A female can lay between 25,000 and 75,000 eggs in an evening, and up to 10 million in a season.
The transparent eggs are pelagic and hatch after 15–20 hours. The initial larvae have a large yolk sac and lack functional eyes, gut or fins. After 48 hours, the yolk is absorbed and the larvae have more of a resemblance to normal fish. These larvae feed on plankton and grow rapidly, and after around 3–4 weeks from hatching, they settle on the substrate.
Unlike some related species, the rock beauty does not act as a cleaner fish.
The rock beauty is one of the more popular Caribbean marine angelfish species in the aquarium trade. The trade was supplied exclusively by wild-caught specimens until captive breeding of this species appeared in the 2020s.
Source: Wikipedia: Rock beauty — https://en.wikipedia.org/wiki/Rock_beauty (CC BY-SA 4.0). Accessed 2026-09-25.
Related in Rock beauty
Links follow this subject's own source article.
Elsewhere in Rock beauty
Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Rock beauty (CC BY-SA 4.0).
- Classification: the source article's taxobox; order, family and genus checked against WoRMS, the World Register of Marine Species (CC BY 4.0).
- Conservation status: IUCN Red List assessment.
- Occurrence records: GBIF (CC0 / CC BY). Basemap: Natural Earth (public domain).
- Biology values: FishBase species summary (CC BY-NC 3.0, non-commercial).
- Word definitions: the , each quoted from its Wikipedia article.
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