LETHRINIDAE Lethrinus mahsena(photo by Surapong Banchongmanee) Lethrinus mahsena (Forsskål, 1775) Sky Emperor D X, 9; A III, 8; P1 13; P2 I, 5; LLp 46-48. Body moderately elongate, compressed. Head profile around eye nearly straight. Outer surface of maxilla with a longitudinal ridge. Sides of jaws with rounded or molar teeth. Fourth dorsalfin spine longest. First or second analfin soft ray longest. Four and half scale rows between dorsal-fin base and lateral line; 3 to 6 scales in supratemporal patch; inner surface of pectoral fin axil covered with scales. Color: body pale greenish gray dorsally, shading to white ventrally. Opercular membrane sometimes red. A variable amount of red basally on spinous portion of dorsal fin. A red bar on pectoral-fin base. Size: maximum length about 65 cm. Distribution: distributed in the western Indian Ocean and Andaman Sea. Remarks: occurs on or near coral reefs to depths of about 100 m. Feeds on a wide variety of benthic invertebrates and fishes. (Hiroyuki Motomura)