Bumphead damselfish (Microspathodon bairdii)

Classification (WoRMS)

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

Accepted name: Microspathodon bairdii · Authority: (Gill, 1862) · Taxonomic status: accepted · AphiaID: 281570.

Synonyms and superseded combinations recorded for this taxon: Pomacentrus bairdii Gill, 1862.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=281570 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (FishBase)

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

Maximum length: 25 cm · Depth range: 3–8 m · Habitat zone: reef-associated · Body shape: short and / or deep · Vulnerability index: 20.5 of 100.

FishBase notes: Adults inhabit rocky inshore reefs exposed to wave action and currents. Primarily herbivorous but occasionally takes a baited hook (Ref. 28023). Oviparous, distinct pairing during breeding (Ref. 205). Eggs are deposited in crevices among the rocks in areas of strong current, usually in the lee of the current (Ref. 28023). Males guard and aerate the eggs (Ref. 205).

Source: FishBase species summary (SpecCode 12453) — https://www.fishbase.se/summary/Microspathodon-bairdii.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

957 georeferenced occurrence records for Microspathodon bairdii are published through GBIF from 7 countries or marine areas. The map above plots 67 distinct locations from a sample of 957 records, omitting 25 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: Ecuador (449); Mexico (380); Panama (66); Costa Rica (49); Colombia (9); Nicaragua (2); El Salvador (2).

Source: GBIF Occurrence Search (taxonKey 2398747) — https://www.gbif.org/occurrence/search?taxon_key=2398747&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=281570 (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 Microspathodon bairdii (Gill, 1862) 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 183472) — https://www.iucnredlist.org/species/183472/0; GBIF IUCN Red List category endpoint (taxonKey 2398747) — https://api.gbif.org/v1/species/2398747/iucnRedListCategory. Accessed 2026-09-23.

Description and natural history (Wikipedia)

Microspathodon bairdii is a large damselfish reaching 25 cm in standard length. The adults are dark brown or black, have purple eyes and sport a large bump on their foreheads. Juveniles are bright blue on their backs, with orange or yellow on the underside.

Microspathodon bairdii is endemic to the Eastern Pacific where its occurs from the mouth of the Gulf of California in Mexico south to Ecuador. Its range includes the Revillagigedo, Cocos, Malpelo and Galapagos Islands.

Microspathodon bairdii occurs on rocky inshore reefs exposed to wave action and currents, being found down to 15 m. It is most frequently recorded in the vicinity large boulders in the shallow subtidal zone. In the Gulf of Chiriquí, Panamá, the bumphead damselfish is found among huge corals and exposed shallow rocky reefs. It is mainly herbivorous, feeding on algae, but will take a hook baited with animal matter and will readily eat meat in the aquarium. They form pairs to breed and the eggs are laid in crevices in rocks where there is a strong current, on the leeward side of the current. The eggs are hoarded and aerated by the male.

The person that Gill was honouring with the specific name has not been identified but it is very probably Spencer Fullerton Baird who was director of the United States National Museum where the type specimen is located.

Source: Wikipedia: Microspathodon bairdii — https://en.wikipedia.org/wiki/Microspathodon_bairdii (CC BY-SA 4.0). Accessed 2026-09-23.