Swift, predaceous schooling fishes (genus Sarda) of the mackerel family (Scombridae). Bonitos, found worldwide, have a striped back and silvery belly and grow to about 30 in. (75 cm) long. Like tunas, they are streamlined, with a narrow tail base, a forked tail, and a row of small finlets behind the dorsal and anal fins. Bonitos have both commercial and sporting value. The three generally recognized species are found in the Atlantic and Mediterranean, the Indo-Pacific, and the Pacific.