Fin's Fish Guide
The Convict surgeon (Acanthurus triostegus) is a saltwater fish of the family Acanthuridae that grows up to 27 cm.
Description
The convict surgeonfish (Acanthurus triostegus) is a surgeonfish of the family Acanthuridae from the Indian and Pacific Oceans. The species has a deep, laterally compressed, silvery body with five to six narrow, black vertical bands resembling a convict's costume. It reaches about 27 cm and inhabits lagoon and seaward reefs with hard substrate; juveniles are abundant in tide pools. It is an algae-eater that grazes filamentous algae from rocks in large aggregations, often near freshwater run-offs. On each side of the caudal peduncle the species bears a sharp, scalpel-like spine that can cause cuts.
Frequently asked questions
How do you recognise the Convict surgeon?
The Convict surgeon has a flattened, disc-shaped body, is mainly silver-grey and shows a vertical stripes pattern. Five to six black bands (convict suit); sharp scalpel spine on the caudal peduncle. Note: in tropical areas this species can cause ciguatera poisoning when eaten; large specimens of coral reef predators can accumulate the toxin. Eat with caution or avoid in risk areas.
Where does the Convict surgeon live?
The Convict surgeon lives in the sea (marine waters) and is mostly found around stony or rocky ground. Coral reefs of the Indian and Pacific Oceans.
How big does the Convict surgeon get?
The Convict surgeon grows to a maximum of about 27 cm. On average the species is around 17 cm.
Is the Convict surgeon dangerous to humans?
The Convict surgeon is venomous — handle spines with care and seek medical help after a sting if needed. The sharp spine on each side of the caudal peduncle can cause deep cuts; do not grab the fish by the tail. Clean and disinfect the wound and seek medical help for a deep cut. Do not eat the species in ciguatera areas: in case of tingling, nausea or reversed hot-cold sensation after consumption, seek medical help.
Is the Convict surgeon edible?
Yes, the Convict surgeon is commonly eaten.
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All data
Identification
Appearance
Habitat & distribution
Behaviour & biology
For anglers
Safety
Status & sources
Same genus Acanthurus
More from the family Acanthuridae
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Point your camera at the fish and Fin names the species in seconds. Free, and the Convict surgeon is one of 12,519 species in the app.