Indonesian Sawtail

The Indonesian sawtail (Prionurus chrysurus), also called the yellowtail sawtail, is a surgeonfish of the family Acanthuridae. The World Register of Marine Species (WoRMS) lists Prionurus chrysurus Randall, 2001 as the accepted name, and FishBase gives Indonesian sawtail as its English name. Wikipedia says John E. Randall described it in 2001, with its type locality given as "the blue lagoon" at Padang Bai on Bali.

FishBase gives a maximum published length of 30 cm (standard length) and a short, deep, compressed body. Wikipedia describes the overall colour as brown, with thin vermillion bars on the flanks and a yellow caudal fin, and a row of 8 to 10 keeled bony plates on the middle of the rear flanks.

FishBase lists the species as Data Deficient on the IUCN Red List (version 2025-2, global) and gives the assessment date as 7 May 2010; Wikipedia, citing the same Red List entry, dates it 2012.

FishBase gives its range as the Western Pacific, in Indonesia only, and its habitat as marine and reef-associated at 5 to 40 m depth. Wikipedia says it is known only from Indonesia, from Bali to western Flores and off Lombok, and that it prefers upwellings where the water is 20 to 23 °C; FishBase also says it prefers areas with cool upwellings.

Where Divers Find Them

At Waterloo in the Amed area of Bali, Dive Concepts says "There are also large schools of the Endemic Yellowtail Sawtail here." It does not name the species or say how often they are seen; this entry places the sighting by the common name, which Wikipedia gives for P. chrysurus.

FishBase says it is found swimming in loose groups around rocky outcrops, usually in high-energy zones, and sometimes alone or in pairs.

Underwater Encounter Behavior

The sources cited here do not describe how the Indonesian sawtail reacts to divers. FishBase lists it as harmless to humans.