Day Shift

Orangeband SurgeonfishBluespined Unicornfish
Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata
Class: Osteichthys Family: Acanthuridae Genus: Naso Species: unicornis
Scientific name: Naso unicornis)

Common name: Bluespined Unicornfish
Hawaiian name: Kala (meaning “thorn”)
This large member of the surgeonfish family is part of the day shift and is easily recognized by its prominent short, unicorn-like horn and blue spines at the base of its tail.

They occur all over the Indian Ocean and in the western and central Pacific Ocean. They commonly are found in surge zones and shallow water channels where they feed on larger, coarser, leafy seaweeds such as Sargassum, Padina and Laurencia spp. They also feed on gelatinous plankton such as comb jellies and jellyfish.

Where there is one there are usually many and in Hawaii they share this habitat with others such as the Whitebar surgeonfish and the convict tang with which they school.

Adult males are discernable (like the one in the center of the photo above) because they have better developed and more prominent horn or rostrum, better developed spines at the base of the tail and longer tail filaments. Pairs breed by casting their eggs and sperm into the surface waters to be carried away on the currents.

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