Description:

Dorsal spines: 11; Dorsal rays: 12 - 15 (usually 14); Anal spines: 4; Anal soft rays: 9. 
Shape: Fusiform, deep-bodied, laterally compressed holocentrid - similar shape to that of S. spiniferum but does not get as large.
Dorsal profile of head slightly convex. Cheek scales in 4 or 5 oblique rows. Maxilla extends posteriorly from below front of pupil to below centre of the eye. Anterior end of nasal bone with 2 short diverging spines. 1-3 spinules on anterior and posterior margins of nasal fossa. Adults' preopercular spines long subequal to orbit diameter. 2 opercular spines with the lower nearly as long or equal to the upper spine; 4th dorsal spine longest; membranes of spinous dorsal fin not incised. Body scales are ctenoid, with the posterior edge finely serrated (ctenii) or feathered, creating a rough texture.
 

Body color brownish to purplish red, each scale with a vertical silvery white line on flank typically preceded by diffuse dark band. A triangular bright red patch above base of pectoral fin. Head primarily red; upper part of opercular membrane blackish with white edge. Spin­ous portion of dorsal fin light red, the membrane tips white, with a submarginal scarlet line. Remaining fins pale red, the membranes of spinous portion of anal fin bright red. Lead edge of pelvic fin white. 3rd anal spine large and white.

Size:

Maturity: Lm unknown.  Range unknown.
Max length : 45.0 cm TL.

Habitat and Ecology:

Naturally uncommon. Reef-associated, depth 0 - 100 m, usually 1 - 15 m. Usually associated with rich coral growth. Solitary and secretive species, occasionally seen in small crevices in clear water habitats. Strictly nocturnal, feeds mainly on benthic crabs and shrimps. Spine of preopercle is venomous.

Fishery Status:

This species is not protected or subject to fishery regulations. It is considered to be naturally rare in occurrence and it is a very rare component of the artisanal catch.

Notes:

Spine of preopercle is venomous. 
Specimen shown in photos here: TL 27.75 cm. SL 23.75 cm.

Recorded by J.L.B. Smith in Aldabra (Smith 1955) and central Seychelles (Smith & Smith 1963) as Holocentrus violaceus.

References:

Froese, R. & D. Pauly. Eds. (2025). FishBase. Sargocentron violaceum. https://www.fishbase.se/summary/Sargocentron-violaceum (30/08/25).
Randall, J.E. & Heemstra, P.C. (1985). A Review of the Squirrelfishes of the Subfamily Holocentrinae from the Western Indian Ocean and Red Sea. Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology, Grahamstown, South Africa. Number 49, January 1985. ISBN 0-86810-116-8.
Smith, J.L.B. (1955). The fishes of Aldabra. Annals and Magazine of Natural History: Series 12, 8:88, 304-312.
Smith, J.L.B. & M.M. Smith. (1963). The Fishes o f Seychelles. Dept. Ichthyology, Rhodes University, Grahamstown; 215 pp.
Williams, I. & Greenfield, D. (2016). Sargocentron violaceum (errata version published in 2017). The IUCN Red List 2016: e.T67903174A115446823. https://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T67903174A67906375.en. (30/08/25).

Citation:

Nevill, J.E.G. (2025). Sargocentron violaceum, Violet squirrelfish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/sargocentron-violaceum-bleeker-1853/