POLYNEMIDAE Filimanus xanthonema, 10.0 cm SL (photo by Seishi Kimura) Filimanus xanthonema (Valenciennes, 1831) Yellowthread Threadfin D VIII+I, 11-13, 9; A III, 10-12; P1 13-15+6 filaments; P2 I, 5; LLp 43-52; GR 36-46. Body moderately elongate, compressed; body depth 2.9-3.7 in SL. Snout pointed; occipital profile nearly straight. Posterior margin of maxilla extending slightly beyond a vertical through posterior margin of adipose eyelid; depth of posterior margin of maxilla less than eye diameter. Lip on lower jaw well-developed, dentary teeth restricted to dorsal surface; vomer with an inconspicuous tooth plate. Longest pectoral filament reaching anal fin origin. Lateral line simple, extending from upper end of gill opening to mid-distal margin of caudalfin membrane. Supraneural bones 3. Color: upper sides of head and trunk with brown tinge, becoming golden on lower sides. Posterior margins of first, second dorsal, anal, and caudal fins blackish, remaining parts yellowish. Pectoral fin mostly black; pectoral filament base white, becoming yellowishwhite on posterior tips. Pelvic-fin base white, other parts yellowish. Size: maximum length 14 cm SL. Distribution: distributed in the eastern Indian and western Pacific Oceans, from east coast of India east to Lombok Island, Indonesia. Remarks: occurs on muddy bottoms in depths of 1 to 30 m. Sex changing from male to female with growth. Feeds on small crustaceans, especially Mysidacea and shrimps.