GOBIIDAE Gobiodon rivulatus, 1.8 cm SL (photo by Ukkrit Satapoomin) Gobiodon rivulatus (Rüppell, 1830) Rippled Coralgoby D VI + I, 9-10; A I, 8-9; P1 17-20; LR 0; PDS 0. Body ovate, well compressed. Head compressed; snout rounded or slightly pointed; jaws subequal; gill opening narrow, restricted to pectoral-fin base; tongue narrow, with rounded anterior margin. Usually anterior some spines of first dorsal fin slightly longer than posterior spines, forming triangular fin; pelvic fins small, united medially; frenum present. No scales on head and body. Sensory canals and pores present on head; reduced longitudinal pattern of sensory papillae on cheek; a pair of sensory papillae just behind chin. Color: ground color of head, body and fins varies from right reddish brown to blackish; numerous wavy vertical blue lines on head and body. Size: 3.0 cm SL. Distribution: Indo-West Pacific. Remarks: found amongst branches of acroporid corals.