Description:
Dorsal spines: 9; Dorsal rays: 14-16; Anal spines: 3; Anal rays: 9-10.
Small to medium-sized grouper with oblong body and relatively small head. Dorsal head profile evenly convex and interorbital area slightly convex.
Posterior and anterior nostrils subequal in size. A pair of small canines present at front of jaws. Mid-side of lower jaw with two rows of teeth, the
inner teeth depressible and twice as long as outer teeth. Palatine teeth present. Pre-operculum rounded and finely serrate. Dorsal fin origin over rear
end of operculum. Dorsal fin membranes slightly incised in juveniles but not in adults. Pectoral fins rounded. Caudal peduncle relatively long and fin
truncate.
Colour. Adults greenish or reddish brown to brownish grey. A distinctive large squarish white blotch on the upper flank. Several narrow curved dark bars
on the midlateral part of the body and dark brown spot midlaterally on paler caudal peduncle. 3 to 5 blue lines (often broken into spots) across the head.
The upper two lines may serve as margins for a mask-like dark band from the snout to the end of the opercle, enclosing the eye. Region under the maxilla
and along the edge of the gill opening often orange. Soft dorsal and anal fins with narrow blue margin. Caudal fin pale with dark leading edges.
Juveniles brown or violet with bright red margins on the dorsal, anal and caudal fins.
Colour may change drastically postmortem losing all distinguishing characteristics in which case the species is best recognised by its rounded face,
enlarged canine teeth, and relatively long and narrow caudal peduncle.
Size:
Maturity: Unknown. Max length : 40.0 cm TL.
Habitat and Ecology:
Rare throughout its range G. albomarginata inhabits steep outer reef slopes and channels adjacent to deep water (depth 6-120 m, usually 15-120 m) usually
found hovering above the bottom. Usually solitary. Piscivore.
Fishery Status:
This species is not protected or subject to fishery regulations. Not recorded in artisanal catch during 2013-2022 survey period ( J. Nevill pers obs).
Notes:
Photo courtesy Eleanor Brighton and Chris Mason-Parker (c) 2022 Blue Safari Seychelles/Marine Conservation Society, Seychelles. Photograph taken at Alphonse group 2022.
References:
Bray, D.J. (2018). Gracila albomarginata in Fishes of Australia, https://fishesofaustralia.net.au/home/species/4515 (14/08/22).
Choat, J.H. et al. (2018). Gracila albomarginata. The IUCN Red List 2018: https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T132800A100568967.en. (14/08/22).
Craig, M.T. et al. (2011). Groupers of the World - a field and market guide. NISC (Pty) Ltd, South Africa. ISBN: 978-1-920033-11-8
Froese, R. & D. Pauly. (Eds.) (2022). FishBase. https://www.fishbase.se/summary/Gracila-albomarginata.html (14/08/22).
Citation:
Nevill, J.E.G., Brighton, E. & Mason-Parker, C. (2022). Gracila albomarginata, Masked grouper. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/gracila-albomarginata-fowler-bean-1930/