Bluestriped fangblenny (Plagiotremus rhinorhynchos)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Chordata · Class: Teleostei · Order: Blenniiformes · Family: Blenniidae · Genus: Plagiotremus.

Accepted name: Plagiotremus rhinorhynchos · Authority: (Bleeker, 1852) · Taxonomic status: accepted · AphiaID: 219334.

Synonyms and superseded combinations recorded for this taxon: Aspidontus rhinorhynchops (Bleeker, 1852); Aspidontus rhinorhynchos (Bleeker, 1852); Petroscirtes amblyrhynchos Bleeker, 1857; Petroscirtes amblyrhynchus Bleeker, 1857; Petroscirtes rhinorhynchos Bleeker, 1852; Petroscirtes rhinorhynchus Bleeker, 1852; Petroscirtes rhynorhynchus Bleeker, 1852; Petroskirtes amblyrhynchos Bleeker, 1857; Petroskirtes rhinorhijnchos Bleeker, 1852; Petroskirtes rhinorhynchos Bleeker, 1852; Plagiotremus rhinorhynchus (Bleeker, 1852); Plagiotremus rhinorhyncos (Bleeker, 1852); Plagiotremus rhynorhynchus (Bleeker, 1852); Plagiotremus rhynorhyncus (Bleeker, 1852); Runula amblyrhynchus (Bleeker, 1857); Runula rhinorhynchos (Bleeker, 1852).

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=219334 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (FishBase)

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

Maximum length: 12 cm · Depth range: 1–40 m · Habitat zone: reef-associated · Body shape: elongated · Vulnerability index: 10 of 100 · Fishery importance: commercial · Aquarium trade: commercial.

FishBase notes: Adults inhabit clear, coral-rich areas of lagoon and seaward reefs (Ref. 1602). They hide in deserted worm tubes or other small holes when alarmed (Ref. 1602, 48636), bite divers occassionally (Ref. 90102). They feed on the skin, mucus and sometimes scales of other fishes by quick attacks. Oviparous. Eggs are demersal and adhesive (Ref. 205), and are attached to the substrate via a filamentous, adhesive pad or pedestal (Ref. 94114). Larvae are planktonic, often found in shallow, coastal waters (Ref. 94114). Juveniles mimic the cleaner wrasse Labroides dimidiatus (Ref. 9710). According to Ref. 53299 they are facultative mimics that change their color: at cleaning stations they mimic the cleaner wrasse and attack unsuspecting customers; elsewhere they adopt an alternative color and striping pattern to conceal themselves among fish shoals from which they can strike at passing fish.

Source: FishBase species summary (SpecCode 6071) — https://www.fishbase.se/summary/Plagiotremus-rhinorhynchos.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

2,895 georeferenced occurrence records for Plagiotremus rhinorhynchos are published through GBIF from 56 countries or marine areas. The map above plots 404 distinct locations from a sample of 2,895 records, omitting 75 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: Australia (1,392); Indonesia (261); New Caledonia (178); Philippines (104); South Africa (101).

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

Source: GBIF Occurrence Search (taxonKey 2395981) — https://www.gbif.org/occurrence/search?taxon_key=2395981&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=219334 (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 Plagiotremus rhinorhynchos (Bleeker, 1852) 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 48342477) — https://www.iucnredlist.org/species/48342477/0; GBIF IUCN Red List category endpoint (taxonKey 2395981) — https://api.gbif.org/v1/species/2395981/iucnRedListCategory. Accessed 2026-09-23.

Description and natural history (Wikipedia)

The fangblenny is a specialised mimic of juvenile bluestreak cleaner wrasse. Those fish serve as cleaners to larger host fish, which attend to have ectoparasites removed. The fangblenny does no cleaning, but bites the host fish and leaves.

From before birth, their eggs are demersal and adhesive and attach to substrates via a filamentous adhesive pad or pedestal. The bluestriped fangblenny can attain around 90mm in length. Two distinct colour phases of this fish are present; blue with a black stripe from snout to tail, or orange with two narrow blue lines from snout to tail. Unlike most blennies, the bluestriped fangblenny is free swimming. Adults inhabit clear, coral-rich areas of lagoon and seaward reefs and it is fairly common on both coral and rocky reefs, usually occurring singly or in pairs. They are known for being aggressive and feed on skin, mucus and sometimes other fish scales. They bite divers when alarmed.

Bluestriped fangblenny mimic the juvenile bluestreak cleaner wrasse, Labroides dimidiatus, to enable them to loiter at cleaner stations and dupe clients waiting to be cleaned. Their success in this aggressive mimicry is, like Batesian mimicry, frequency-dependent: it works best when the mimic is rare compared to the genuinely symbiotic cleaner fish.

Source: Wikipedia: Bluestriped fangblenny — https://en.wikipedia.org/wiki/Bluestriped_fangblenny (CC BY-SA 4.0). Accessed 2026-09-23.