Ribbon moray (Rhinomuraena quaesita)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Anguilliformes · Family: Muraenidae · Genus: Rhinomuraena.

Accepted name: Rhinomuraena quaesita · Authority: Garman, 1888 · Taxonomic status: accepted · AphiaID: 217529.

Synonyms and superseded combinations recorded for this taxon: Rhinomuraea quaesita Garman, 1888; Rhinomuraena ambonensis Barbour, 1908.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=217529 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (FishBase)

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

Maximum length: 130 cm · Depth range: 1–67 m · Habitat zone: reef-associated · Body shape: eel-like · Vulnerability index: 78 of 100 · Fishery importance: commercial · Aquarium trade: commercial.

FishBase notes: Adults occur in lagoon and seaward reefs. They are secretive species normally hidden in sand or rubble, sometimes with only its head protruding. Feed on small fishes (Ref. 9710, 48635, 75154, 89972). Juveniles all black, males have yellow dorsal fin and females change to a nearly all yellow color, but usually with blue in the posterior (Ref. 48635). Only moray that undergoes abrupt changes in coloration and sex: it is a protandrous hermaphrodite, i.e., functioning males reverse sex to become females. Protandry is diagnosed based on colouration, but not confirmed (Ref. 103751).

Source: FishBase species summary (SpecCode 8594) — https://www.fishbase.se/summary/Rhinomuraena-quaesita.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

1,181 georeferenced occurrence records for Rhinomuraena quaesita are published through GBIF from 36 countries or marine areas. The map above plots 160 distinct locations from a sample of 1,181 records, omitting 28 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: Indonesia (615); Philippines (217); Fiji (74); Malaysia (42); South Africa (25).

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

Source: GBIF Occurrence Search (taxonKey 2404128) — https://www.gbif.org/occurrence/search?taxon_key=2404128&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=217529 (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 Rhinomuraena quaesita Garman, 1888 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 155301) — https://www.iucnredlist.org/species/155301/0; GBIF IUCN Red List category endpoint (taxonKey 2404128) — https://api.gbif.org/v1/species/2404128/iucnRedListCategory. Accessed 2026-09-23.

Description and natural history (Wikipedia)

The ribbon eel is the only species in its genus, Rhinomuraena, in the subfamily Muraeninae of the moray eel family. Its unique morphology, such as its gonad structure and function, are not shared with many of the other major genera in the family and provided evidence for separation. Typically, eels of the family urogenital system follow a posterior pattern toward the anus of the eel, but the Rhinomuraena system has its sex cells move anteriorly. This change is presumed to be due to some evolutionary cause, like peripatric speciation. Previously, R. quaesita was used to identify the blue ribbon eels and R. amboinensis was used for black ribbon eels, but these are now recognized as the same species, R. quaesita.

Its closest known relative is the pink-lipped moray (Echidna rhodochilus), which does not form a monophyletic group with the other Echidna species.

Typically, ribbon eels can be found in tropical parts of the Indian and Pacific Ocean, ranging from East Africa to southern Japan, Australia, and French Polynesia. This species is widely distributed and are seen by divers in Indonesian waters with their heads and anterior bodies protruding from crevices in sand and rubble habitats, like coral reefs, which they are able to slip through with their slime coat.

Ribbon eels prefer relatively shallow waters, frequenting a depth range of 1 to 57 meters.

In their juvenile and subadult stages, ribbon eels appear primarily jet black with a yellow dorsal fin. In adult males, the black is replaced by a vibrant blue and yellow facial appearance. An adult female is entirely yellow or yellow with some blue to the posterior.

Color change related to sex change is not known from any other moray eel species. The blue adult males range from 65 to 94 cm in length, while the larger yellow females can reach up to 130 cm.

The ribbon eel larva is described as a large, greenish leptocephalus.

Ribbon eels are labeled "least concerned" on the IUCN Red List of Threatened Species as of 2009. Recent studies on the effects of various environmental factors on marine eels have presented potential threats to the ribbon eel population. Marine eels that prefer to stay in shallower waters, specifically around coral reef habitats, are most at risk of suffering from the impacts of coral bleaching and other marine habitat damage caused by climate change or human activity (i.e. pollution). The shift in habitat structure and diversity could make it harder for ribbon eels to find enough prey to survive and reproduce. Overfishing is another concern as it can lead to a reduction in the number of ribbon eels and their available prey.

Most ribbon eels do not live longer than a year in captivity. Ribbon eels have been observed in many cases to stop eating after being captured and put into home aquariums. Higher levels of success have been achieved in public aquaria, where there are a few reported cases of spawning at facilities in Europe and North America. In captivity, the color differences are not related to maturity or sex.

Although captured for the aquarium industry, it remains common and widespread, and is not considered threatened.

Source: Wikipedia: Ribbon eel — https://en.wikipedia.org/wiki/Ribbon_eel (CC BY-SA 4.0). Accessed 2026-09-23.