Yellowtail sergeant (Abudefduf notatus)

Classification (WoRMS)

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

Accepted name: Abudefduf notatus · Authority: (Day, 1870) · Taxonomic status: accepted · AphiaID: 212870.

Synonyms and superseded combinations recorded for this taxon: Abudefduf clarki Snyder, 1911; Chrysiptera paucifasciata Fowler, 1946; Glyphidodon notatus Day, 1870; Indoglyphidodon abbotti Fowler, 1944.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=212870 (CC BY 4.0). Accessed 2026-09-25.

Biology and life history (FishBase)

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

Maximum length: 17 cm · Depth range: 1–12 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 10 of 100 · Fishery importance: of no interest.

FishBase notes: Found in small groups along upper edges of sheltered drop-offs. Also found in rocky inshore reefs with moderate to strong wave action. In roving aggregations and somewhat difficult to approach (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).

Source: FishBase species summary (SpecCode 5686) — https://www.fishbase.se/summary/Abudefduf-notatus.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.

Distribution and occurrence records (GBIF)

411 georeferenced occurrence records for Abudefduf notatus are published through GBIF from 30 countries or marine areas. The map above plots 126 distinct locations from a sample of 411 records, omitting 15 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 (84); Japan (51); Thailand (46); Korea, Republic of (38); Indonesia (33); Seychelles (27); Christmas Island (22); Chinese Taipei (16); Yemen (12); French Southern Territories (10); Maldives (9); Mozambique (8); United States Minor Outlying Islands (8); India (6); Réunion (6).

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

Source: GBIF Occurrence Search (taxonKey 2398703) — https://www.gbif.org/occurrence/search?taxon_key=2398703&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=212870 (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 Abudefduf notatus (Day, 1870) 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 188537) — https://www.iucnredlist.org/species/188537/0; GBIF IUCN Red List category endpoint (taxonKey 2398703) — https://api.gbif.org/v1/species/2398703/iucnRedListCategory. Accessed 2026-09-25.

Description and natural history (Wikipedia)

This species of damselfish is found in the Indo-Pacific. In the Indian Ocean, it occurs in the Gulf of Aden, the Arabian Sea, eastern Africa, Madagascar, Seychelles, the Maldives, Sri Lanka, the Andaman Sea, Indonesia, and Australia.

In the Pacific Ocean, it occurs in the Gulf of Thailand, Indonesia, the Great Barrier Reef around Australia, the Philippines, Taiwan, Japan, New Caledonia, and various islands in the western Pacific Ocean. It typically occurs at depths of 1 to 12 m. Adults live in coral reefs and lagoons while juveniles are found in the open sea.

The species can grow up to a maximum length of up to 17 cm. It is gray with 5 vertical black bands and a yellow caudal fin. It has 13 dorsal spines, 13 to 14 dorsal soft rays, 2 anal spines, and 13 to 14 anal soft rays.

Abudefduf notatus forms roving aggregations which are noted to be rather difficult to approach. It is an oviparous species, with individuals forming distinct pairs during breeding and males guarding and aerating eggs.

Abudefduf notatus is found in the aquarium trade.

Source: Wikipedia: Abudefduf notatus — https://en.wikipedia.org/wiki/Abudefduf_notatus (CC BY-SA 4.0). Accessed 2026-09-25.