Distinctive Characters: Two dorsal fins separated by a small interspace (not larger than eye). The first dorsal fin with 14-16 spines, the second followed by 7-9 finlets. Anal fin with 14-15 rays followed by 7 finlets. Pectoral fin with 26-28 rays. Body scaleless except for the corselet and lateral line.
Colour: Back dark purplish blue. Lower side and belly silvery, with 4-6 very conspicuous longitudinal dark bands (which in live specimens may appear as discontinuous lines of dark blotches).
Habitat and Biology: Epipelagic and oceanic usually above the thermocline. Forms massive schools together with juvenile yellowfin tuna. Feeds on small fishes, cephalopods and crustaceans.
Distribution: Tropical and warm temperate waters throughout the world.
Remarks: Katsuwonus pelamis is the most commercially important species in the Maldives. This one species accounts for about two thirds of the toal recorded fish catch. It is caught almost exclusively in the livebait pole and line fishery. This is a traditional fishery that has almost certainly been in existence for over one thousand years.