Brachygenys jessiae

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Eupercaria incertae sedis · Family: Haemulidae · Genus: Brachygenys.

Accepted name: Brachygenys jessiae · Authority: (Jordan & Bollman, 1890) · Taxonomic status: accepted · AphiaID: 1577331.

Synonyms and superseded combinations recorded for this taxon: Xenocys jessiae Jordan & Bollman, 1890.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=1577331 (CC BY 4.0). Accessed 2026-09-25.

Biology and life history (FishBase)

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

Maximum length: 30 cm · Depth range: 3–18 m · Habitat zone: reef-associated · Body shape: elongated · Vulnerability index: 20 of 100 · Aquarium trade: never/rarely.

FishBase notes: Forms large daytime aggregations along walls and over rocky slopes, often in somewhat protected areas (Ref. 5227).

Source: FishBase species summary (SpecCode 25502) — https://www.fishbase.se/summary/Brachygenys-jessiae.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.

Distribution and occurrence records (GBIF)

353 georeferenced occurrence records for Brachygenys jessiae are published through GBIF from 1 countries or marine areas. The map above plots 17 distinct locations from a sample of 353 records; it shows where the species has been observed and reported, not a modelled range.

Most records by country or area: Ecuador (353).

Source: GBIF Occurrence Search (taxonKey 12168691) — https://www.gbif.org/occurrence/search?taxon_key=12168691&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=1577331 (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 Brachygenys jessiae (Jordan & Bollman, 1890) as Vulnerable (code VU). 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 183395) — https://www.iucnredlist.org/species/183395/0; GBIF IUCN Red List category endpoint (taxonKey 12168691) — https://api.gbif.org/v1/species/12168691/iucnRedListCategory. Accessed 2026-09-25.

Description and natural history (Wikipedia)

Brachygenys jessiae has a relatively slender, elongated body, notably different from most related species. The head is conical in shape and has large eyes and a short diagonal mouth with a protruding lower jaw. It has very small teeth which are set in bands on the flaws and the palate.

The dorsal fin is not continuous, the anterior spiny portion is completely divided from the posterior soft- rayed part. The dorsal fin contains 10 spines in the anterior portion and a single spine and 13-14 soft rays. The anal fin has 3 small spines and 10-11 soft rays. This species attains a maximum total length of 30 cm.

The back is dark silvery-grey in colour, frequently showing yellowish green, yellowish blue or blue-green tints. The colour shades to paler silver on the flanks and to silvery-white on the underparts. There are 7 black, horizontal stripes along the flanks.

Distribution

Brachygenys jessiae is found in the eastern Pacific Ocean where it is endemic to the waters around the Galápagos Islands.

Habitat and biology

Brachygenys jessiae is found at depths between 0 and 20 m. It forms dense schools in these shallow waters.

These spend the day along rock walls and over rocky slopes. They feed on plankton and small fishes. It is an oviparous species, spawning in distinct pairs.

Systematics

Brachygenys jessiae was first formally described in 1890 by the American ichthyologists David Starr Jordan (1851–1931) and Charles Harvey Bollman (1868–1889) with the type locality given as Isla Santa Maria in the Galápagos Islands of Ecuador. This species is placed in the monotypic genus Xenocys by some authorities. This was done when Haemulon was determined to be paraphyletic in molecular studies which showed Haemulon chrysargyreum, the type species of Felipe Poey's Brachygenys, clustered with Xenistius californianus.

The genus was therefore revived to include also includes the other species in Xenistius and this species. This change has been accepted by Catalog of Fishes but not by Fishbase. The specific name honours Jordan's second wife Jessie Knight Jordan (1866–1952).

Source: Wikipedia: Brachygenys jessiae — https://en.wikipedia.org/wiki/Brachygenys_jessiae (CC BY-SA 4.0). Accessed 2026-09-25.