Also known as Doctorfish, Lancetfish, Ringtail Doctorfish, Ringtail Surgeon, Ringtail Surgeonfish, Thorntail, Thorntail Fish.
Found in small schools often mixing with other similar species, over shallow protected reef flats and slopes of lagoons and outer reef walls. They look almost black with only a white band around the tail and orange around the spine (this is not always visible)
They feed on algae.
Juveniles between soft corals in very shallow lagoons.
Length - 45cm
Depth - 1-20m
Widespread Western Indian Ocean
Surgeonfish have a blade like spine in the tail that points outwards when bent, unicorns have two hook-like plates along the tail, these are used for defence and are as sharp as a surgeons scalpel, hence the name "Surgeonfish".
Some species are venomous. Ref: https://www.fishbase.se/summary/4748