Unlike other members of Scomberomorus, the King mackerel (Scomberomorus cavalla) lacks a black area on the anterior portion of the first dorsal fin. The King mackerel has 12-18 spines in its first dorsal fin; 15-18 rays in the second dorsal fin, which are followed by 7-10 finlets; and 21-23 pectoral fin rays. Its body is about five times the size of its head, and about six times as long as it is deep. The entire body is covered with rudimentary scales, except for its pectoral fin. A unique feature of the King is the lateral line which drops sharply after the second dorsal fin, and then continues on to the tail. distinguishing it from the Cero mackerel
(Scomberomorus regalis). The King mackerel also lacks scales on the pectoral fins as does the Spanish mackerel
(Scomberomorus maculatus), in contrast to the cero mackerel which has scales extending onto the pectoral fin.
The main colorization of the King mackerel is silver with indistinct bars or spots on its side. The dorsal surface is black with iridescent tones of blue and green. Young fish have small bronze spots in 5 or 6 irregular rows. The King mackerel prefers outer reefs and coastal waters. Resident populations are found in northeastern Brazil, Louisiana, and south Florida waters. King mackerels occur in depths between 75.5 - 111.5 feet (23 - 34 m). Dependent upon warm temperatures, king mackerel can migrate along the east coast of the U.S. The Gulf of Mexico and Atlantic populations migrate separately, with the division lines being in Volusia-Flagler counties of southeast Florida in November through March and in Monroe-Collier counties of southwest Florida during April through October.