ELEOTRIDAE Butis butis, 7.4 cm SL (photo by Koichi Shibukawa) Butis butis (Hamilton, 1822) Duckbill Sleeper D VI+I, 8; A I, 8; P1 18-19; LR 29-31; Pred.S 25-33. Body elongate, subcylindrical and compressed posteriorly. Head depressed; snout elongate and depressed, duck-bill shaped; bony interorbital serration around dorsal margin of eye; jaws large, extending posteriorly to below anterior margin of eye; lower jaw protruding beyond upper jaw. Pelvic fins widely separated. Cheek, operculum and interorbital with ctenoid scales; scales present between eye and interorbital bony ridge; small auxiliary scale between large body scales. Color: blackish brown, with several indistinct, longitudinal black lines on body; base of pectoral fin with a distinct large black spot edged with two vivid red spots anteriorly. Size: 14.5 cm. Distribution: Indo-West Pacific. Remarks: found in tidal estuaries. Carnivorous. Often marketed fresh.