Oxymonacanthus longirostris (Bloch & Schneider, 1801)
Oxymonacanthus longirostris (Bloch & Schneider, 1801)
Genus: ,

Scientific Name: Oxymonacanthus longirostris

English Name: Harlequin filefish

Creole Name:

French Name: Poisson lime à taches oranges

IUCN Red List Status: Vulnerable (VU)


Dorsal spines: 2 (2nd spine not visible); Dorsal rays: 31-35; Anal spines: 0; Anal rays: 29-32. 

A small slender leatherjacket. Body elongate. Snout elongate and pointed. Small terminal mouth. First dorsal fin origin above eye. Pelvic fin rudiment 
absent. Males with slightly elongate bristles on caudal peduncle. 

Colour. Base colour greenish. Rows of orange-yellow spots and dashes along body. A small black blotch on the on caudal fin. 


Maturity: Unknown. Max length: 12.0 cm TL.

Habitat and Ecology:

Occurs in clear lagoon and seaward reefs (depth 1-35 m). Found in pairs or small groups. Nests near bases of dead corals, often on clumps of algae. 
Monogamous. An obligate coralivore, feeding exclusively on Acropora polyps. Feeding takes place throughout the day becoming less towards the evening. 
Shelter amongst branches of Acropora corals at night.

Fishery Status:

This species is not protected or subject to fishery regulations. 


Coral bleaching can rapidly affect this corallivorous species. At Cousine island (Seychelles) this species declined rapidly after extensive 
coral mortality in 1998 from a mean of 6.4 individuals per count in 1997 to 0.0 individuals per count in 1999 (Spalding and Jarvis 2002).
The occurrence of healthy acroporid corals, which appear to be particularly susceptible to coral bleaching is essential to the survival of this species 
in the wild.
Photos courtesy and (c) 2023 Green Islands Foundation (GIF). 


Bray, D.J. (2022). Oxymonacanthus longirostris in Fishes of Australia, https://fishesofaustralia.net.au/home/species/812 (24/10/23). 
Froese, R. & D. Pauly. Eds. (2023). FishBase. Oxymonacanthus longirostris. https://www.fishbase.se/summary/6559 (24/10/23). 
Matsuura, K. & Motomura, H. (2016). Oxymonacanthus longirostris. The IUCN Red List 2016 (errata version 2017): https://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T70010721A70011814.en. (24/10/23).
Spalding, M.D. & Jarvis, G. (2002). Impacts of the 1998 coral mortality on reef fish communities in the Seychelles. Marine Pollution Bulletin 44: 309-321. 


Nevill, J.E.G. & Accouche, W. (2023). Oxymonacanthus longirostris, Harlequin filefish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/oxymonacanthus-longirostris-bloch-schneider-1801/

Upload your videos
Share this post

There are no comments

Leave a Reply

Your email address will not be published. Required fields are marked *

Start typing and press Enter to search

Generic filters
Exact matches only
Shopping Cart

No products in the cart.