Compressed and elongate body, scaly. Lower jaw with fleshy barbel at the tip. A series of VIII?XII isolated dorsal spines preceding a soft dorsal fin, having 23-28 rays; anal fin with 25-28 rays; anus and pelvics far apart; rounded caudal fin. Well developed lateral line. Total vertebrae 59-64, abdominal 24-26 and caudal 35-38; abdominal vertebrae with 2 equal lateral extensions. Color: brownish with irregular light vertical bars, or with several light horizontal stripes or uniform yellow.|
Similar families occurring in the area. Fistulariidae: a distinct caudalfin filament; body depressed rather than compressed; no spines before soft dorsal fin. Solenostomidae: smaller, dorsal-fin spines not isolated; no lateral line; body variously covered with cutaneous papillae.
Remarks. Usually occurring on reefs alongside larger herbivorous fish or in a head-down vertical orientation, as ambush hunter of small fishes and crustaceans. Recorded maximum length about 80 cm.