Naso brevirostris   (Cuvier,  1829) (Fish)
Organism information awaits expert curation
Class: Actinopterygii

Image copyrights: Randall, J.E.

Size: 42-60 cm.

Color: Adults bluish grey to olivaceous brown in color, commonly pale anteriorly and on cheek and throat; short irregular lines on sides of body; diagonal lines on horn; lip edges blue. Sub adults with dark spots on head and body.

Height 2.2-2.7, 2.6-2.8 in length with caudal, measured from tip of snout to end of caudal. Head 4-4.2, 4.8-5 in length with caudal. Eye 3.1-4.4, 1.9-2.8 in convex and slightly keeled inter orbital space. Frontal horn horizontal, its axis in the level of the middle of the eye. In a specimen of 135 mm it is developed as a bump, not projecting beyond the vertical through anterior end of jaws, in a specimen of 183 mm its reaches that vertical, and in a specimen of 335 mm, the larger examined, it projects far before the mouth, its length being 3.9 diameters of eye. Profile of snout between horn and mouth vertical, sub vertical in young specimens, 18-24 pointed crenulate teeth in each ramus of both jaws, the anterior ones in the upper jaw longer than the others. Origin of dorsal a short distance behind vertical through hind border of eye. Spines strong, heteracanth, sub equal, as long as snout or somewhat shorter in large specimens. Dorsal rays gradually decreasing in length posteriorly, the last 1-1.5 diameters of eye. Third anal spine longer than second, less than dorsal spine in length, anal rays slightly decreasing in length posteriorly. anal less deep than dorsal. Pectorals as long as snout and eye or snout and half eye. Ventral spine strong, longer than dorsal spines. Caudal truncate or slightly emarginate. Two spines on each side of caudal peduncle, small and knod-like in young, black-like in adults. Juveniles lack the prominent horn of adults. Dorsal spines (total): 6; Dorsal soft rays (total): 27-29; Anal spines: 2; Anal soft rays: 27-30.

Dioecious, external fertilization, nonguarders, open water/substratum egg scatterers. Paired spawning.

Remarks: Values in above description denote proportions.

Synonym (s)
Cyphomycter coryphaenoides Smith, 1955
(Junior synonym)
Naseus brevirostris Cuvier, 1829
(Senior synonym)
Naseus brevirostris Valenciennes, 1835
(Junior synonym)
Naso brevirostris (Cuvier, 1829)
(Senior synonym)
Naso brevirostris (Valenciennes, 1835)
(Junior synonym)
Keris amboinensis Bleeker, 1852
Naseus brevirostris Bleeker, 1853, 1855
Priodon amboinensis Bleeker, 1854
Naseus amboinensis Bleeker, 1857
Naseus brevirostris Gunther, 1861
Naseus brevirostris Klunzinger, 1871
Naseus brevirostris Gunther, 1875
Naseus brevirostris Day, 1876
Naseus brevirostris Klunzinger, 1884
Acanthurus brevirostris Jenkins, 1904
Acanthurus brevirostris Jordan and Evermann, 1905
Acanthurus brevirostris Sterindachner, 1906
Acanthurus brevirostris Kendall and Goldsborough, 1911
Naseus amboinensis M. Weber, 1913
Naso brevirostris Fowler, 1928
Naso brevirostris Fowler and Bean, 1929
Naso brevirostris Herre, 1936
Naso brevirostris Fowler, 1938
Naseus brevirostris Cuvier and Valenciennes, 1835
Naso brevirostris Smith, 1949

Common Name (s)
• Spotted Unicornfish (English)
• Short-nosed Unicorn-fish (English)
• Thol kilathi
• Thumbi
• Ammas
• Karukkan
• Mudiyan
• Short-nose Unicornfish
Economic Importance and Threats
Importance:  Commercial, Dangers
(Fisheries, aquarium, Ornamental fish
Causes ciguatera poisoning)

Habitat:  Bentho Pelagic, Reef Associated, Coastal
Trophic Level:  Consumer
Prey:  Benthic and filamentous algae, zooplankton, other plants
Predator:  Thunnus obesus (fish)


• Lakshadweep (Lat: 11) (Long: 72.5) INDIA
• Lakshadweep, Kavaratti Atoll (Lat: 10.55) (Long: 72.63) INDIA (Record: 01/1991-06/1992)
• Tamil Nadu, Chennai INDIA
• Tamil Nadu, Gulf of Mannar INDIA
• Lakshadweep, Agatti INDIA
• Lakshadweep, Bangaram INDIA
• Lakshadweep, Bitra INDIA
• Lakshadweep, Minicoy INDIA
• Lakshadweep INDIA
• Red Sea
• Palk Bay INDIA
• Lakshadweep Islands INDIA (Record: 11/1993-01/1997)
• Tamil Nadu, Pamban INDIA

Literature Source(s)
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  • James, C; O'Farrell, S; Hamylton, S; Ingwersen, C and Walker, R The coral reef resources of Mu Ko Surin national park, Thailand Coral Cay Conservation Available at -
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  • Allen, GR (2005) Reef fishes of northwestern Madagascar RAP Bulletin of Biological Assessment 31 39-48
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  • Society for the Management of European Biodiversity Data (2009) World Register of Marine Species (WoRMS) Available at -
  • Froese, R and Pauly, D (2000) Fishbase 2000: Concepts, design and data sources ICLARM 344 pp Available at -
  • Anand, PEV and Pillai, NGK (2003) Habitat distribution and species diversity of coral reef fishes in the reefslope of the Kavaratti atoll, Lakshadweep, India Journal of the Marine Biological Association of India The Marine Biological Association of India, Cochin 45(1) 88-98 Available at - NIO, Goa
  • Marine Biological Station, Chennai, Tamil Nadu (2003) Checklist of marine fauna of Tamil Nadu Department of Environment, Government of Tamil Nadu Available at -
  • Beaufort, LF and Chapman, WM (1951) The fishes of the Indo-Australian Archipelago A. J. Reprints agency, Karol Bagh, New Delhi 9 484 pp Available at - NIO, Goa
  • Jones, S and Kumaran, M (1980) Fishes of the Laccadive Archipelago The Nature Conservation and Aquatic Sciences Service, Trivandrum, Kerala 760 pp Available at - NIO, Goa
  • Dr. Kumaraguru, AK (2000) Studies on socioeconomics of Coral Reef resource users in the Gulf of Mannar coast, South India Centre for Marine and Coastal studies School of Energy, Environment and Natural Resources Madurai Kamaraj University, Madurai, India Available at -
  • Murty, VS (1996) Marine ornamental fishes of India Proceedings of the Seminar on Fisheries - A Multibillion Dollar Industry, Madras CMFRI 23-34 Available at -
  • Murty, VS (2002) Marine ornamental fish resources of Lakshadweep CMFRI Special Publication CMFRI 72 1-134 Available at -
  • Murty, VS (1969) Catalogue of fishes (excluding from the Laccadives) in the reference collections of the Central Marine Fisheries Research Institute Bulletin of Central Marine Research Institute CMFRI, Cochin 10 1-38 Available at -
  • Murty, VS (2001) Ornamental fish resources of Lakshadweep Bulletins of the Geological Survey of India 56 103-111 Available at -
  • Pillai, PKM and Augustine, SK (2000) A code list of common marine living resources of the Indian seas CMFRI Special Publication No.12 CMFRI 1-115 Available at -

Page last updated on:2011-12-07

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