Description:

Dorsal spines: 8; Dorsal rays: 24-27; Anal spines: 3; Anal rays: 22-25.

Dark orangish-brown body with slightly irregular, longitudinal blue lines breaking into small spots anteriorly. Prominent black spot at rear base of dorsal and anal fins 
and extending onto body. Adults have blue iris. Dorsal and anal fins dark brown with lighter brown on distal portions. Tail lunate and dark brown, yellow in juveniles. 
 

Maturity: Lm unknown. Range unknown. Max Length: 22cm TL

Inhabits coral and rubble areas in lagoons and seaward reefs (8-53m depth, usually 10-50m). Usually solitary. Grazes on surface algae and detritus. 
 

This species is not protected or subject to fishery regulations. It is caught in the fish trap fishery.

Clements, K.D. et al. (2012). Ctenochaetus binotatus. The IUCN Red List 2012: e.T177955A1501829. http://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T177955A1501829.en. (15/10/18).
Froese, R. & D. Pauly. Eds. (2018). FishBase. https://www.fishbase.de/summary/ctenochaetus-binotatus (15/10/18)
Randall, J.E. (2001). Surgeonfishes of Hawaii and the World. ISBN: 1-56647-561-9

Nevill, J.E.G. (2019). Ctenochaetus binotatus, Twospot surgeonfish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/ctenochaetus-binotatus-randall-1955/ (edited 15/06/22).