Description:

Dorsal spines: 3; Dorsal rays: 30-35; Anal spines: 0; Anal rays: 28-31.

A dark greenish-black to purplish triggerfish with pale blue lines along the bases of the soft dorsal and anal fins. Submarginal blue line on caudal fin bends into lobes. 
Blue disappears with death, leaving black fish with white line along base of soft dorsal and anal fins. The scales on the rear of the body have prominent keels that form 
longitudinal ridges.
 

Maturity: Lm unknown. Range unknown. Max Length: 50cm TL.

Inhabit upper reef edge of outer slope of seaward reefs (depth 0-75m, usually 0-20m) often in small loose aggregations. Classified as a planktivore but has very variable 
diet including benthic algae and drifting offal. The fact it is caught in the hand line fishery reflects this diverse diet.

This species is not protected or subject to fishery regulations. It is caught in the hand line fishery but is a rare component of the catch.

Similar to the Indian triggerfish (Melicthys indicus), that may occur in Seychelles waters but has yet to be documented, which has a rounded caudal fin with narrow 
white margin.

Bray, D.J. (2016). Melichthys niger in Fishes of Australia, http://fishesofaustralia.net.au/home/species/764 (31/10/18)
Froese, R. & D. Pauly. Eds. (2018). FishBase  https://www.fishbase.de/summary/melichthys-niger (31/10/18)
Liu, J. et al. (2015). Melichthys niger (errata version published in 2016). The IUCN Red List 2015: https://www.iucnredlist.org/species/193609/97666184 (31/10/18).

Nevill, J.E.G. (2019). Melichthys niger, Black triggerfish. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/melichthys-niger-bloch-1786/ (edited 18/06/22).