Also known as Dark Surgeon, Dark Surgeonfish, Dark Tang, Elongated Surgeonfish, Doctorfish, Lancetfish, Ringtail Surgeon, Ringtail Tang, Tailring Surgeon, Tailring Surgeonfish, Thorntail, Thorntail Fish, Whitetail Lancet.
Found in small schools over sandy areas of outer lagoons and seaward reefs rich in algae growth.
They feed on algae.
Length - 42cm
Depth - 2-15m
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/4750