Description:

Dorsal spines: 9; Dorsal rays: 24-27; Anal spines: 3; Anal rays: 22-24.

Brown to pale lavender-brown, with or without fine bluish grey longitudinal lines or rows of dots on body. Nape and chest with small orange spots, lips blackish. 
Pale pectoral fins with upper edge narrowly black; pelvic fins brown. A black spot larger than pupil at rear base of dorsal fin, and a smaller spot at rear base 
of anal fin. Blue edge with submarginal black line to dorsal and anal fins. Peduncle spine with black socket. Lunate caudal fin with a narrow white posterior margin.

Maturity: Lm unknown. Range 10-14cm TL. Max Length: 21.0cm TL. Acanthurus nigrofuscus is one of the smallest surgeonfishes.

Found on hard substrates of shallow lagoon and seaward reefs to below the surge zone (depth range 0-25m typically 2-25m). Classified as a grazer feeding on algal turf 
in large schools that overwhelm the territorial defences of other herbivores. Forms large spawning aggregations at the most seaward extension of the reef. At Aldabra 
Atoll it was observed to spawn before the new/full moon during November-December in the channels between lagoon and open ocean (Robertson 1983).

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

Choat, J.H. et al. (2012). Acanthurus nigrofuscus. The IUCN Red List 2012: e.T178019A1523035. http://dx.doi.org/10.2305/IUCN.UK.2012.RLTS.T178019A1523035.en. (14/10/18).
Froese, R. & D. Pauly. Eds. (2018). FishBase. https://www.fishbase.de/summary/acanthurus-nigrofuscus  (14/10/18)
Randall, J.E. (2001). Surgeonfishes of Hawaii and the World. ISBN: 1-56647-561-9
Robertson, D.R. (1983). On the spawning behavior and spawning cycles of eight surgeonfishes (Acanthuridae) from the Indo-Pacific. Environmental Biology of Fishes 9(3/4): 193-223.

Nevill, J.E.G. & Mason-Parker, C. (2019). Acanthurus nigrofuscus, Brown surgeonfish. www.seatizens.sc https://seatizens.sc/species/acanthurus-nigrofuscus-forsskal-1775/ (edited 14/06/22).