Picasso triggerfish
A small, territorial triggerfish with trichromatic vision.
Last updated
The Picasso triggerfish is also known as the lagoon triggerfish or blackbar triggerfish.[1] It is a triggerfish species that reaches up to 30 cm in length.[1] This fish is found on reefs in the Indo-Pacific region.[1]
Scientific classification
- KingdomAnimalia
- PhylumChordata
- ClassActinopterygii
- DivisionTeleostei
- OrderTetraodontiformes
- FamilyBalistidae
- GenusRhinecanthus
- SpeciesRhinecanthus aculeatus
Named by (Linnaeus, 1758)
Sources: Wikipedia taxobox: Lagoon triggerfish (CC BY-SA 4.0) · order, family and genus agree with WoRMS AphiaID 219890 (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, 0.3 m, next to a 1.8 m person.
Diagram: drawn by Codexery, schematic shapes to scale (not a likeness). Length: Wikipedia: Lagoon triggerfish
Where the picasso triggerfish has been recorded
Each dot is a place where the species has been observed and reported (5,718 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)
Biology and range
Males hold territories for significantly longer than females.[2] A typical male territory may overlap with one to five female territories.[2] Their mating system is described as haremic.[2] Mothers guard and care for eggs until they hatch, while paternal care is normal in teleost fishes with external fertilization.[2]
Territories are defended by both sexes, and some individuals hold a territory for eight years or more, with males typically retaining theirs for a longer duration than females.[2] When a male or female vanishes, a different fish quickly occupies their territory.[2] This species spawns repeatedly throughout its life.[2] For roughly 12–14 hours, the mother stays above the eggs, using her pectoral fins to fan them for about 30% of that period.[2]
What the specialist sources record
The GBIF Backbone Taxonomy accepts the species as Rhinecanthus aculeatus (Linnaeus, 1758).[3] GBIF holds 6,567 occurrence records for this taxon as of 19 October 2026.[3] The fish possesses a single cone with an opsin most sensitive at 413 nm, and a double cone containing opsins most sensitive at 480 nm and 530 nm.[4] Behavioral studies indicate that, similar to humans, this species has trichromatic vision.[4]
Maternal guarding greatly reduces egg predation; when mothers were experimentally taken away, nearly all eggs failed to survive.[2] While tending eggs, mothers reduce their foraging and restrict it to a small area close to the egg mass.[2] Because males mate with multiple females, maternal care is viewed as an evolutionarily stable strategy.[2]
References
- Wikipedia, "Lagoon triggerfish" (CC BY-SA 4.0), which cites: "Species Rhinecanthus aculeatus Linnaeus 1758", FishWisePro, 1758 (original not read by us) en.wikipedia.org
- Wikipedia, "Lagoon triggerfish" (CC BY-SA 4.0), which cites: Kuwamura, "Evolution of Female Egg Care in Haremic Triggerfish, Rhinecanthus aculeatus", Ethology, 1997, p. 1015–1023 (original not read by us) en.wikipedia.org
- GBIF Backbone Taxonomy and occurrence index, Rhinecanthus aculeatus (taxon key 2407235). CC BY 4.0 (backbone); counts are facts. gbif.org
- Wikipedia, "Lagoon triggerfish" (CC BY-SA 4.0), which cites: S = short wavelength, M = middle wavelength, L = long wavelength; Marshall, "Vision down under", Fraser Island, 2004; Pignatelli, "Double cones are used for colour discrimination in the reef fish, Rhinecanthus aculeatus", Biology Letters, 2010, p. 537–539 (original not read by us) en.wikipedia.org
Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Lagoon triggerfish (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.
More in Other Reef Fish
Elsewhere in Reef Aquarium Species
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: Lagoon triggerfish (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).
- Word definitions: the Codexery glossary, each quoted from its Wikipedia article.
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