FISTULARIIDAE Cornetfishes By Ukkrit Satapoomin Fistularia commersonii Large fishes attaining to about 2 m TL. Body extremely elongate and slightly depressed. Snout prolonged and tubular, hexagonal in cross section, mouth small, without barbels. Scaleless or with tiny prickles and rows of scutes. Dorsal or anal fins short based and opposite, with 14-17 segmented soft rays; pectoral fins with 13-17 soft rays; pelvic fins small and abdominal, with 6 soft rays. Forked caudal fin with elongate filament formed by the middle 2 caudal fin rays. Well developed lateral line, anterior portion arched to almost middorsal and extending onto caudal filament. Color: variable with the species, either red to orange-brown above and silvery below, or brownish olive above, lighter below, with a series of blue spots on back and snout. Similar families occurring in the area. Aulostomidae: no caudal fin filament present; barbel present on lower jaw; body compressed rather than depressed; distinct separate spines anterior to soft dorsal fin. Syngnathidae: smaller; body covered with armor; anal fin reduced or absent; no caudal fin filament present. Belonidae: no caudal fin filament present; mouth large, both jaws produced into slender beak, lower jaw longer, with single series of distinct canines. Remarks. Fistularia petimba is typically found in coastal areas over soft bottoms, at depths greater than 10 m. Fistularia commersonii is most often seen in seagrass beds and coral reefs. Feed on small fishes and crustaceans.