Also known as Doctorfishes, Galapagos Surgeonfish, Lancetfishes, Razor Sawtail, Thorntails, Thorntail Fish, Yellowtail Doctorfish, Yellowtail Surgeonfish, Yellow-tailed Sawfish, Yellow-tailed Surgeonfish.
Found in large schools grazing on algae from corals and rocks over shallow areas of coastlines and lagoons rich in algae growth.
They feed on algae.
Length - 60cm
Depth - 3-30m
Widespread Eastern Central Pacific
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/13417