Description:

Dorsal spines: 6; Dorsal rays: 27-30; Anal spines: 2; Anal rays: 27-30.

Full bodied lateral profile. Yellowish to olivaceous grey dorsally, paler ventrally. Horn-like process in front of eye that does not extend anterior to mouth. Dorsal and 
anal fins yellowish with narrow blue stripes. Peduncular plates and keels blue; lips whitish or blue, dorsal and anal fins with a blue margin. Caudal fin emarginate 
when young, truncate with filamentous lobes in adult, orange basally, shading to grey, with a broad pale greenish posterior border; caudal filaments edged in blue.
 

Maturity: Lm unknown. Range unknown. Max Length: 70cm FL.

Reef associated (depth 1-180m) found in inshore coral and seaward reefs. Feeds on macroscopic algae, mainly larger brown algae (Turbinaria and Dictyota). Typically occurring
in small groups, sometimes solitary. Juveniles in shallow protected bays and harbours. 
 

This species is not protected or subject to fishery regulations. It is caught in the fish trap fishery, but is a rare component of the catch.

Froese, R. & D. Pauly. Eds. (2018). FishBase https://www.fishbase.de/summary/Naso-unicornis (18/10/18)
McIlwain, J. et al. (2012). Naso unicornis. The IUCN Red List 2012: e.T177970A1506556. http://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T177970A1506556.en. (18/10/18).
Randall, J.E. (2001). Surgeonfishes of Hawaii and the World. ISBN: 1-56647-561-9

Nevill, J.E.G. (2019). Naso unicornis, Bluespine unicornfish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/naso-unicornis-forsskal-1775/ (edited 17/06/22).