Bluespine unicornfish

(Naso unicornis)


Bluespine unicornfish IUCN LEAST CONCERN (LC)


Facts about this animal

The bluespine unicorn is large unicornfish, reaching a length of up to 70 cm. It is characterized by a bony horn projecting from the head in front of the eyes. The tail (in adults) is truncate with filamentous lobes. There are two blue plates bearing knife-like spines on either side of the caudal peduncle. Horn and caudal peduncule spines are better developed in males than in females. The dorsal fin has 6 spines and 27-30 soft rays, the anal fin 2 spines and 27-30 soft rays.

The colour of the bluespine unicornfish is usually greenish-grey. The dorsal and anal fins are yellowish with thin blue lines.

Bluespine unicorns are diurnal and are found singly, in pairs, or in small groups. They are omnivores feeding primarily on brown algae (Sargassum and Dictyota) and zooplankton.

Did you know?
how many species of surgeonfish do exist? The Acanthuridae family contains six genera with about 80 species, including the genus Naso, the unicorns, with 19 different species.


Name (Scientific) Naso unicornis
Name (English) Bluespine unicornfish
Name (French) Nason à éperons bleus
Name (German) Blauklingen-Nasendoktorfisch
Name (Spanish) Narbero de aguijón azul, Pez unicornio de nariz corta
Local names Licorne vache, KornPujuFiantandrokaRufia espigão azulLabahita, Mangadlit, Surahan, Tarian, Tudluan
CITES Status Not listed
CMS Status Mot listed



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BS Thurner Hof



Range Indian Ocean from the coast of East Africa, and Red Sea, to the Pacific Ocean as far east as the Hawaiian, Marquesas and Tuamoto islands, north to southern Japan, south to Lord Howe and Rapa islands.
Habitat Coral reefs from surface to 180 m depth.
Wild population Unknown
Zoo population Considering that most publc aquaria are not part of the WAZA system and do not register their collections with ISIS, available ISIS data are not significant.

In the Zoo

Bluespine unicornfish


How this animal should be transported

For air transport, Container Note 51 of the IATA Live Animals Regulations should be followed.

Fish must be unpacked carefully and under low illumination.


Find this animal on ZooLex


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Why do zoos keep this animal

Bluespine unicornfish are not an endangered species but their habitats, coral reefs, are threatened in many places. They are thus presented by zoos and aquariums as an ambassador species for reef protection.