Description:

Dorsal spines: 10; Dorsal rays: 9; Anal spines: 3; Anal rays: 8.

Body moderately elongate. Snout moderately elongate. Posterior nostril a longitudinal opening, closer to orbit than anterior nostril. Lateral teeth in jaws conical. Cheek 
without scales. 

Colour. Body grey, lighter ventrally, often with scattered irregular dark blotches. In life or freshly caught body maybe brown with large evenly spaced white blotches. 
The snout has broad indistinct streaks radiating from the eye to the mouth. The upper jaw particularly towards the corner of the mouth can show red colouration. 
Dorsal fin brown with distal portions of rays reddish. Pectoral fin pale with yellow stripe along 2nd and 3rd rays. Caudal fin brownish with reddish posterior margin. 
Large males in breeding condition may develop a reddish hue to the face and fins.

Maturity: Lm unknown. Range 34 - ? cm. Max Length: 100 cm TL. Commonly 70 cm TL.

Largest and the longest-snouted Lethrinid.

Inhabits sandy coastal areas, lagoons and reef slopes (depth 1 -185 m). Juveniles are found in shallow sandy areas often in large schools. Adults deep along coastal slopes 
and drop-offs, usually solitary. Feeds mostly on fish, crustaceans and cephalopods. Very active and swims fast.

This species is not protected or subject to fishery regulations. It is caught in the hand line fishery, where it is a regular but not typically numerous component of the catch.

Colours tend to be paler and less distinct in small specimens which can be mistaken for L. microdon.

Carpenter, K.E. & Allen, G.R. (1989). FAO Species Catalogue. Vol. 9 Emperor Fishes and Large-eye Breams of the World (Family Lethrinidae). An annotated and Illustrated 
Catalogue of Lethrinid Species Known to Date. UNFAO Rome. ISBN 92-5-102889-3
Carpenter, K.E. et al. (2016). Lethrinus olivaceus. The IUCN Red List 2016: http://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T16720328A16722400.en. (12/05/19).
Froese, R. & D. Pauly. (Eds.) (2019). FishBase. https://www.fishbase.se/summary/Lethrinus-olivaceus (12/05/19).
Nevill, J. (2013). A Species Identification Guide for Commonly Caught Fish in the Seychelles Near-Shore Artisanal Fishery. GOS/UNDP/GEF.

Nevill, J.E.G. (2019). Lethrinus olivaceus, Longface emperor. Seychelles Seatizens. www.seatizens.sc. https://seatizens.sc/species/lethrinus-olivaceus-valenciennes-1830/ (edited 17/07/22).