Western talma (Chelmonops curiosus)
Source-cited species reference: taxonomy from WoRMS, biology from FishBase, occurrence map from GBIF, conservation from IUCN Red List, description from Wikipedia.
Last updated
Rick Stuart-Smith / Reef Life Survey · via Wikipedia: Chelmonops curiosus · CC BY 3.0
Chelmonops curiosus, truncate coralfish, truncate butterflyfish, western talma or squareback butterflyfish, is a species of marine ray-finned fish, a butterflyfish from the family Chaetodontidae. It is endemic to Australia.
Scientific classification
- KingdomAnimalia
- PhylumChordata
- ClassActinopterygii
- DivisionTeleostei
- OrderAcanthuriformes
- FamilyChaetodontidae
- GenusChelmonops
- SpeciesChelmonops curiosus
Named by Kuiter, 1986
Close relatives
Other species of Chelmonops with a Codexery entry.
- Eastern talma Chelmonops truncatus
Sources: Wikipedia taxobox: Chelmonops curiosus (CC BY-SA 4.0) · order, family and genus agree with WoRMS AphiaID 280141 (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, 0.26 m, next to a 1.8 m person.
Diagram: drawn by Codexery, schematic shapes to scale (not a likeness). Length: Wikipedia: Chelmonops curiosus
Where the western talma (chelmonops curiosus) has been recorded
Each dot is a place where the species has been observed and reported (2,745 records, half-degree grid) — not a modelled range. 15 inland records left out (institution coordinates).
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: Chaetodontidae · Genus: Chelmonops.
Accepted name: Chelmonops curiosus · Authority: Kuiter, 1986 · Taxonomic status: accepted · AphiaID: 280141.
Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=280141 (CC BY 4.0). Accessed 2026-09-25.
Biology and life history (FishBase)
Measured values published by FishBase for Chelmonops curiosus. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.
Maximum length: 26 cm · Depth range: 51–57 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 16 of 100 · Aquarium trade: never/rarely.
FishBase notes: A generally common species found in vertical rock faces. Feed on worms and crustaceans. Oviparous (Ref. 205). Form pairs during breeding (Ref. 205).
Source: FishBase species summary (SpecCode 25434) — https://www.fishbase.se/summary/Chelmonops-curiosus.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.
Distribution and occurrence records (GBIF)
2,745 georeferenced occurrence records for Chelmonops curiosus are published through GBIF from 1 countries or marine areas. The map above plots 45 distinct locations from a sample of 2,745 records, omitting 23 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: Australia (2,745).
The full country table, WoRMS marine regions and the sampling notes are on this species' Distribution page.
Source: GBIF Occurrence Search (taxonKey 2385302) — https://www.gbif.org/occurrence/search?taxon_key=2385302&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=280141 (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 Chelmonops curiosus Kuiter, 1986 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 165706) — https://www.iucnredlist.org/species/165706/0; GBIF IUCN Red List category endpoint (taxonKey 2385302) — https://api.gbif.org/v1/species/2385302/iucnRedListCategory. Accessed 2026-09-25.
Description and natural history (Wikipedia)
Chelmonops curiosus has a very deep strongly compressed body, which is more than half its standard length. It has a small head with a long, tapered snout and a tiny mouth at the end of its snout. There is a single, elongated dorsal fin with the separation between the spiny portion and the soft-rayed portion being hardly visible. The first spine is very small but as they progress towards the posterior they become longer and longer.
In juveniles the soft part of the dorsal fin is rounded but it is pointed in adults and has a triangular profile when raised. The anal fin is smaller than the dorsal fin. The caudal fin is truncate. The background colour of this fish is steel grey with amounts of black shading different for each individual.
They are marked with 4 vertical black bars with silver edged margins, becoming broader towards the tail. The pelvic fins are black.
In juveniles there is an ocellus on the soft part of the dorsal fin which fades as they become mature. The spiny part of the dorsal fin contains 11 spines while the soft part has 25-27 soft rays while the anal fin has 3 spines and 19-20 soft rays. This species attains a maximum total length of 26 cm.
Distribution
Chelmonops curiosus is endemic to the seas of Australia where it is found along the south coast from Victor Harbor, South Australia and on the western coast as far north as Shark Bay, Western Australia.
Habitat and biology
Chelmonops curiosus is found on coastal rocky reefs, seeming to prefer vertical rock faces, often where the water is turbid and they will use man-made structures such as pylons and jetties. The juveniles are frequently found swimming among seaweed beds.
The adults are normally observed in pairs. This species is omnivorous and its diet comprises small worms, crustaceans, and algae. They breed in pairs. They appear to be territorial, with each pair defending a territory.
Utilisation
Chelmonops curiosus is occasionally collected for the aquarium trade. It is rarely exported from Australia.
Source: Wikipedia: Chelmonops curiosus — https://en.wikipedia.org/wiki/Chelmonops_curiosus (CC BY-SA 4.0). Accessed 2026-09-25.
Related in Western talma
Links follow this subject's own source article.
Elsewhere in Western talma
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: Chelmonops curiosus (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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