Description

Also known as Doctorfish, Doubleband Surgeonfish, Doubleband Tang, Lancetfish, Lieutenant Surgeon, Lieutenant Surgeonfish, Lieutenant Tang, Thorntail, Thorntail Fish.

Found singly, or in schools, over silty waters, around slopes, in lagoons, outer reefs and seaward reefs.
They feed on benthic algae.
Length - 31cm
Depth - 1-40m
Widespread 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/1259