---
title: Brown Surgeonfish (Acanthurus nigrofuscus)
scientific_name: Acanthurus nigrofuscus
common_name: Brown Surgeonfish
taxon: Surgeonfishes
conservation_status: LC - Least Concern
published: 2024-11-01T11:37:57.560Z
updated: 2026-08-13T22:32:59.760Z
tags: Brown Surgeonfish, Acanthurus nigrofuscus, Surgeonfishes, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/fishes/bony-fishes/surgeonfishes/brown-surgeonfish
---

# Brown Surgeonfish (*Acanthurus nigrofuscus*)

## Quick facts

- **Group:** Surgeonfishes (*Acanthuridae*)
- **Size:** up to 21 cm
- **Depth:** 0-25 m
- **Diet:** Herbivore
- **Activity:** Diurnal
- **Rarity:** Common
- **Habitat:** Shallow reef flats and slopes, everywhere there is turf
- **Reproduction:** Broadcast spawner, Gonochoric
- **Hazard:** Dangerous
- **Conservation status:** LC - Least Concern

## How to recognise it

- plain brown body with fine blue lines, easy to overlook
- yellow smudge at the base of the pectoral fin
- folding blade on each side of the tail base
- in loose grazing groups that sweep across the reef together
- length up to 21 cm

The plain brown fish that is everywhere and that nobody photographs. On many reefs it is the single most numerous fish present, and the reason the coral is not buried in algae.

Algal turf grows fast enough to smother a reef within weeks. Surgeonfish crop it continuously, and this species does it in roving groups of dozens - which is not sociability but tactics. Damselfish farm their own algal patches and defend them furiously against any single grazer; a group of twenty brown surgeonfish simply swamps the farmer, feeds through the territory and moves on. A lone fish gets driven out, a mob does not.

Each carries the family scalpel at the tail base, folded into a socket until needed.

Twenty-one centimeters (8 in) at most, brown, common, and structurally important. A reef where these disappear becomes an algal reef within a season, which is exactly what has happened in places where herbivores are fished out.

## Also known as

- **English:** brown surgeonfish, Blackspot Surgeonfish, Brown surgeon
- **Arabic:** Juneh, Keen
- **Hebrew:** בתרן שחום
- **French:** Chirurgien brun, Chirurgien brun-noir
- **Italian:** Pesce chirurgo guance maculate
- **German:** Brauner Doktorfisch
- **Spanish:** Pez Cirujano Marrón
- **Portuguese:** Cirurgião Castanho
- **Czech:** bodlok temný
- **Japanese:** ナガニザ, Naganiza
- **Chinese:** 褐斑刺尾鯛
- **Russian:** Бурый хирург
- **AF:** Bruin doktervis
- **CA:** Peix cirurgià cua porpra
- **DA:** Brun Kirurgfisk
- **ET:** Kuldtups-kirurgkala
- **FI:** Keltapilkkuvälskäri
- **FIJ:** Balagi
- **LT:** Rudasis jūrų chirurgas
- **MAL:** നെയ് ത്തള, നെയ്തല, പല
- **MSA:** Debam perang, Barat-barat, Debam
- **TAH:** ma'aua
- **TGL:** Surahan

## Scientific synonyms

- *Acanthurus fuliginosus* Lesson, 1831
- *Acanthurus lineolatus* Valenciennes, 1835
- *Acanthurus matoides* Valenciennes, 1835
- *Acanthurus rubropunctatus* Rüppell, 1829
- *Acronurus lineolatus* Klunziger, 1871
- *Chaetodon nigrofuscus* Forsskål, 1775
- *Ctenodon rubropunctatus* (Rüppell, 1829)
- *Hepatus fuliginosus* (Lesson, 1831)
- *Hepatus lineolatus* (Valenciennes, 1835)
- *Hepatus lucillae* Fowler, 1938
- *Teuthis lucillae* (Fowler, 1938)

## Range

Eritrea, Federal Republic of Somalia, Indian Ocean, Kenya, Mozambique, Red Sea, Seychelles, South Africa

---

*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/fishes/bony-fishes/surgeonfishes/brown-surgeonfish)*
*Updated: August 13, 2026*