Threespot damselfish (Stegastes planifrons)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Ovalentaria incertae sedis · Family: Pomacentridae · Genus: Stegastes.

Accepted name: Stegastes planifrons · Authority: (Cuvier, 1830) · Taxonomic status: accepted · AphiaID: 276679.

Synonyms and superseded combinations recorded for this taxon: Eupomacentrus planifrons (Cuvier, 1830); Pomacentrus planifrons Cuvier, 1830.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=276679 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (FishBase)

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

Maximum length: 13 cm · Depth range: 1–30 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 23.5 of 100 · Fishery importance: commercial · Aquarium trade: commercial.

FishBase notes: Adults inhabit inshore and offshore coral reefs. They are found within caves at night (Ref. 9626). Often found in tangles of staghorn coral; anywhere there is abundant algae on reefs (Ref. 26938). Feed mainly on algae but also on harpacticoid copepods, small gastropods, eggs of mollusks, sponges, polychaetes and hydroids (Ref. 9626). Juveniles subsist on the external parasites of fishes (Ref. 5521). Adults pugnaciously guard large territories, will chase and nip intruders of all sizes, including divers (Ref. 9710). Oviparous, distinct pairing during breeding (Ref. 205). Eggs are demersal and adhere to the substrate (Ref. 205). Males guard and aerate the eggs (Ref. 205). Taken incidentally in traps and small-meshed beach nets (Ref. 5217).

Source: FishBase species summary (SpecCode 3653) — https://www.fishbase.se/summary/Stegastes-planifrons.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

39,978 georeferenced occurrence records for Stegastes planifrons are published through GBIF from 38 countries or marine areas. The map above plots 107 distinct locations from a sample of 3,000 records, omitting 22 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 (30,262); Puerto Rico (2,773); Colombia (2,533); Virgin Islands (U.S.) (1,779); Mexico (1,069).

The full country table, WoRMS marine regions and the sampling notes are on this species' Distribution page.

Source: GBIF Occurrence Search (taxonKey 2398894) — https://www.gbif.org/occurrence/search?taxon_key=2398894&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=276679 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-23.

Conservation status (IUCN Red List)

The IUCN Red List assesses Stegastes planifrons (Cuvier, 1830) 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 188496) — https://www.iucnredlist.org/species/188496/0; GBIF IUCN Red List category endpoint (taxonKey 2398894) — https://api.gbif.org/v1/species/2398894/iucnRedListCategory. Accessed 2026-09-23.

Description and natural history (Wikipedia)

The adult threespot damselfish is a brownish-grey, bony fish with a dusky yellow sheen and a large black spot at the base of the pectoral fins. It grows to 13 cm in length. The large dorsal fin has 12 spines and 15-17 soft rays. The anal fin has two spines and 13-14 soft rays. Neither the pectoral nor pelvic fins have spines.

Juveniles are a much brighter yellow. They have a few tiny blue spots on the head and upper body, including one on the upper iris. They have three distinctive black spots, one at the junction between the dorsal fin spines and the soft rays, one dorsally on the caudal peduncle, and a third smaller one just above the base of the pectoral fins. These tend to have a faint blue rim, and the pectoral spot is absent in very young juveniles, becoming more prominent as the juvenile grows.

The threespot damselfish is found down to about 30 m in the western Atlantic Ocean. Its range extends from Florida through the Caribbean Sea to the Bahamas. It is a demersal fish, and its favoured habitats are inshore and offshore coral reefs. It is often found among staghorn coral and at night may be found in caves.

Threespot damselfish feed mainly on seaweed, but also eat copepods, gastropod molluscs and their eggs, hydroids, marine worms, and sponges.

Adults vigorously maintain large territories, chasing away and nipping intruders, including humans. A male and female will form a breeding pair. The female lays eggs which stick to objects on the seabed, and the male guards these and oxygenates them by fanning them with its fins.

Source: Wikipedia: Stegastes planifrons — https://en.wikipedia.org/wiki/Stegastes_planifrons (CC BY-SA 4.0). Accessed 2026-09-23.