Naso annulatus

From RTAW Reefpedia
Jump to: navigation, search
See Talk:Naso annulatus for individual experiences with this species, Naso annulatus. Feel free to add your own personal experiences.

Common Name
Whitemargin Unicornfish
Binomial Name
Naso annulatus
Fish image required.jpg
Scientific Classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Perciformes
Family: Acanthuridae
Genus: Naso
Species: annulatus

This page that you have visited here is a stub of the RTAW Reefpedia. That means that this page has been generated, but it is yet to contain the relevant information required. So it requires some work on content within it before it is completed.

If you would like to volunteer to help out, please see Help:Contents

Common Names

  • Whitemargin Unicornfish



Brown / dull olive in colour that becomes paler underneath. There are white margins on the pectoral fins. N. annulatus has a large protruding horn growing from its head.

Similar Species

There are two other species with a protruding horn, but this is the largest. Sometimes confused with N. brevirostris.

Maximum Size

100cm [1]

Associated Organisms

Anything that lives in symbiosis, parasitic or opportunistically with it.



Captive Care

Tank Size

This fish is completely unsuited to captive conditions except in large public aquaria due to its size.

Water Flow





Requires regular feedings of macro algae and large zooplankton. In the wild various algae have been recorded as food items for adults, including Caulerpa, Codium, Dictyota and Jania. Gelatinous zooplankton also features prominently in their diet.[1]

Growth Rate

Unless stunted, should reach 80% of its maximum size in the first few years of its life[2].


N. annulatus is subject to the same parasites /diseases that affect other saltwater fish


Juveniles may enter the trade at a modest size and become available in shops. If an aquarist is uncertain regarding identification, best to avoid making the purchase.




Does it have any fish that it should not be housed with?


Does it have coral that it is not compatible with?


Is it compatible with other invertebrates such as molluscs, crustaceans and echinoderms?


How it reproduces, how suitable it is to breeding or captive propagation, techniques on how to etc.

Local Ecology


Indo Pacific: East Africa through to Hawaii & Marquesan Islands through to southern Japan and down to Lord Howe Island [1].


Solitary juveniles can be found in shallow lagoon reefs. Adults are rare above 25m where they form small schools near reef walls [1][2].

Additional Information

Some additional notes on it that don't fit in the above sections.



  1. 1.0 1.1 1.2 1.3 ( Froese, R., Pauly, D. Fish Base, World Wide Web electronic publication, 2008, Retrieved: 10 March 2011.
  2. 2.0 2.1 ( Schultz, H., Unicorns: More Than a Myth in Reef Aquariums; The Genus Naso, Reefkeeping Magazine, 4(6), 2005.