Spotted unicornfish (Short-nosed unicornfish)
Yes, unicornfish exist! and there are about 20 species of them, belonging to the genus Naso, in the Acanthuridae Family.
This one, for example, is Naso brevirostris (Perciformes - Acanthuridae), distinctive by its long, broad-based tapering horn before eye (a bump on forehead of juveniles). This species is olive-brown to grey; has many small dark spots on the head and lower body, and many thin dark bars on the upper body; the tail is whitish with dark blotch at base.
Naso brevirostris is widespread and cosmopolitan, occupying a wide range of habitats. It is found in the Pacific and Indian oceans.
Other common names: Palefin Unicornfish, Shortsnout Unicornfish, Brown Unicornfish, Shortnosed Kala, Shortnose Unicornfish, Longnose Unicornfish, Corne, Nasique, Nason à Rostre Court, Nason Pointillé.
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Photo credit: ©Sue Merrifield