Acanthurus mata
Spot this blue-grey surgeonfish over reefs in the Maldives' Central Atolls or KwaZulu-Natal, comfortable in 24-29°C water year-round.
A slender, oval-bodied surgeonfish reaching around 35 cm, coloured blue-grey to olive with fine dark horizontal lines running along the flanks. Look for the yellow patch at the base of the tail and the pale blue crescent tail itself, plus the sharp caudal spine (the 'scalpel' that gives surgeonfish their name) tucked near the tail base. It often swims in loose groups rather than tight schools, holding a mid-water position off the reef rather than hugging the bottom.
Divers usually find it hovering in loose, mixed groups off the reef edge, feeding on drifting plankton and algae rather than grazing tight to the substrate like many of its relatives. It tends to stay at a comfortable distance from divers without bolting, and is most often noticed mid-water over drop-offs and outer reef slopes rather than in the shallows.
Like other surgeonfish, it carries a razor-sharp spine folded into a groove near the tail, which it can flick out for defence, so it is best admired without close handling.
No clear seasonal pattern shows up in the sighting data, so treat it as a year-round sighting. It sits comfortably in 24.7 to 29.0°C water, a range tropical reefs hold for most of the year across its range.
Reef neighbours a diver could mistake it for. Use the identification notes above to tell them apart.
Most reliably logged in the Maldives, especially the Central Atolls, and a strong presence across Indonesia in Raja Ampat, Nusa Tenggara, West Papua and Sulawesi. Also a solid sighting in KwaZulu-Natal, South Africa, with smaller but consistent numbers in Timor-Leste's Atauro Island, Fiji's Taveuni, French Polynesia, Australia and the Seychelles.
Mapping where Elongate Surgeonfish is logged…
The Maldives, particularly the Central Atolls, offers the most consistent sightings, alongside Indonesia's Raja Ampat, Nusa Tenggara and Sulawesi. KwaZulu-Natal in South Africa and Atauro Island in Timor-Leste are also reliable spots.
There is no strong seasonal signal in the sighting data, so it is considered a year-round encounter on tropical reefs within its 24.7 to 29.0°C comfort range.
Look for a blue-grey, oval-bodied fish around 35 cm with fine dark stripes, a yellow patch at the tail base and a pale blue crescent tail. It usually hovers mid-water in loose groups off the reef rather than hugging the bottom.
They typically reach about 35 cm in length, a mid-sized build for the surgeonfish family.
No, they are not considered dangerous. Like all surgeonfish they carry a sharp defensive spine near the tail, so it is worth avoiding close contact, but they pose no active threat to divers.
Site and sighting data is aggregated from diver logs, iNaturalist and GBIF. For taxonomy and conservation status:
Striped Surgeonfish
3,294 sites
