The king mackerel resembles the Spanish mackerel closely in general appearance, but its pectoral fins are mostly covered with scales; its ventrals are below the first dorsal, instead of definitely behind the origin of the latter; its head is relatively longer, its nose more pointed, its teeth more numerous (about 40 in each jaw), triangular and very sharp pointed; and the upper half of its first dorsal is deep blue. Furthermore, the king mackerel is marked by a narrow brownish stripe running from close behind each pectoral fin to the base of the caudal, crossing the lateral line as the latter bows downward below the second dorsal fin. Its side spots, too, are mostly below the lateral line and arranged in rows, whereas the spots of the Spanish mackerel are irregularly scattered, with about as many above the lateral line as below it.
Said to reach 35 pounds, but the average weight is between 5 and 10 pounds.
Atlantic Coast of North America, Cape Cod to Brazil, abundant among the West Indies and around southern Florida.
This southern fish is recorded by Dr. W. C. Kendall at Monomoy, at the southern elbow of Cape Cod, but it has not been taken elsewhere in the Gulf of Maine.