Animal Species:Bluespine Unicornfish, Naso unicornis (Forsskål, 1775)

The Bluespine Unicornfish is usually greenish-grey and has a bony horn projecting from the head in front of the eyes. It is found in tropical reef waters.

A Bluespine Unicornfish at Harrier Reef

A Bluespine Unicornfish at Harrier Reef
Erik Schlögl © Erik Schlögl

Alternative Name/s

Blue-spine Unicorn, Brown Unicornfish, Longnose Unicornfish, Spotted Unicornfish

Identification

The Bluespine Unicornfish has a bony horn projecting from the head in front of the eyes. There are two blue plates bearing knife-like spines on either side of the caudal peduncle. The tail is emaringate (glossary) in young fish but becomes truncate with filamentous lobes in larger individuals.

The Bluespine Unicornfish is usually greenish-grey. The dorsal and anal fins are yellowish with thin blue lines.

Size range

The species grows to 70 cm in length.

Distribution

The species is found in tropical reef waters of the Indo-Pacific. In Australia it is recorded from south-western to north-western Western Australia and the northern Great Barrier Reef to northern New South Wales.

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Click on the map for detailed information.  Source: Atlas of Living Australia.

Naso unicornis

Distribution by collection data

Ozcam map of Bluespine Unicornfish specimens in the Australian Museum.

What does this mean?

Classification

Species:
unicornis
Genus:
Naso
Family:
Acanthuridae
Order:
Perciformes
Class:
Actinopterygii
Subphylum:
Vertebrata
Phylum:
Chordata
Kingdom:
Animalia

What does this mean?

References

  1. Allen, G.R. 1997. Marine Fishes of Tropical Australia and South-east Asia. Western Australian Museum. Pp. 292.
  2. Allen, G.R. & R. Swainston. 1988. The Marine Fishes of North-Western Australia. A Field Guide for Anglers and Divers. Western Australian Museum. Pp. 201.
  3. Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. New Holland. Pp. 433.
  4. Randall, J.E., Allen, G.R. & R.C. Steene. 1997. Fishes of the Great Barrier Reef and Coral Sea. Crawford House Press. Pp. 557.


Mark McGrouther , Collection Manager, Ichthyology
Last Updated:

Tags Fishes, Ichthyology, Bluespine Unicornfish, Naso unicornis, Acanthuridae, blue, brown, green, yellow, 'normal fish', 30 cm - 1 m, blotches/mottled, coral reef, marine, adult, large lips,