Humpback Unicornfish, Naso brachycentron (Valenciennes 1835)

Other Names: Humpback Unicorn

A Humpback Unicornfish, Naso brachycentron, at Komodo, Komodo, Manggarai, Nusa Tenggara Timur, Indonesia. Source: Mark Rosenstein / License: CC BY Attribution-Noncommercial-ShareAlike

A greyish "hump-backed" surgeonfish with whitish to yellowish on the lower sides, lower half, several scattered small dark-edged pale spots on the rear of the head and above the pectoral fins, and a pair of bony keels on the caudal peduncle. Adult males develop a long tapering horn on the head and have irregular bars on the lower sides.

Cite this page as:
Dianne J. Bray, Naso brachycentron in Fishes of Australia, accessed 19 Apr 2024,

Humpback Unicornfish, Naso brachycentron (Valenciennes 1835)

More Info


Scott Reef, WA, Ashmore Reef, Timor Sea and the northern Great Barrier Reef to Swains Reef, QLD, also reefs in the Coral Sea. The species occurs elsewhere in the tropical, Indo-west-central Pacific. Inhabits seaward reef slopes, either solitary or in small groups.


Dorsal fin IV-V, 28-30; Anal fin II, 27-28. Distinctive humped-back body; horn only in adult males..


Feeds on benthic algae.

Species Citation

Naseus brachycentron Valenciennes, 1835, Hist. Nat. Poiss. 10: 275. Type locality: Waigeo, Indonesia.


Dianne J. Bray


Australian Faunal Directory

Humpback Unicornfish, Naso brachycentron (Valenciennes 1835)


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Quick Facts

CAAB Code:37437025

Conservation:IUCN Least Concern

Depth:8-30 m

Habitat:Reef associated

Max Size:100 cm TL

Species Image Gallery

Species Maps

CAAB distribution map