CHAETODONTIDAE Chaetodon triangulum, 9.0 cm SL (photo by Richard Winterbottom) Chaetodon triangulum Cuvier, 1831 Triangular Butterflyfish D XI, 23-26; A III, 20-21; P1 13-14; LLp 14-26; LR 25-33. Body rounded, deep; snout short, pointed; predorsal contour nearly straight. Lateral line incomplete. Dorsal and anal fins rounded, posterior edge slanting toward caudal peduncle; caudal fin truncate to slightly rounded. Color: pattern of alternating cream-colored and gray-brown to purplish chevron-shaped narrow bar on sides; yellow boomerang-shaped marking on caudal fin in addition to another narrow vertical stripe near edge; a yellow streak crossing caudal peduncle into anal fin; 3 dark bars on head, including one through eye. Size: maximum length about 15 cm. Distribution: Indian Ocean, from East Africa to Java. Remarks: Chaetodon baronessa is its Pacific sibling.