Family BALISTIDAE

Triggerfishes are widespread in shallow tropical and subtropical waters of the Indo-west Pacific, mostly inhabiting shallow coral reefs in depths to 50 m. They are distinguished by the following combination of external characters: body deep, moderately compressed, encased in very thick, tough skin with large scales, those above pectoral-fin base often enlarged to form a flexible tympanum; mouth small and terminal, or almost terminal; teeth strong, eight in the outer series of both jaws; gill opening, a moderately short, vertical to oblique slit in front of pectoral-fin base; two dorsal fins, first dorsal fin with three visible spines, the second spine more than 1/2 length of first spine; first spine capable of being locked in an erect position by second spine; second dorsal and anal fin similar in shape; most dorsal-, anal-, and pectoral-fin rays branched; pelvic fins rudimentary, represented by a series of four pairs of enlarged scales encasingposterior end of pelvis (Matsuura 2001).