Banded rudderfish

Seriola zonata

Family Carangidae - jacks

Distinguishing
Characteristics
Body elongate, moderately deep, slightly compressed; color dark bluish green on back, lighter below, usually a dark band from eye to dorsal fin origin, faint yellowish stripe from head to caudal fin: juveniles with yellowish tint and 6 vertical bars on body; mouth large, extends to or past middle of eye, posterior margin of upper lip broad with a straight margin (not a curved margin); no scutes on lateral line; anal fin preceded by 2 free spines (may be rudimentary in older fish), margin and tip of anal fin lobe whitish; 1st dorsal fin spiny; 2nd dorsal fin starts mid-back and extends to near tail, anterior rays somewhat longer than posterior rays, whitish on tips of anterior rays; anal fin shorter than dorsal fin; pelvic fins longer than pectoral fins; grooves present on caudal peduncle.
Similar Species
The 4 species of the genus Seriola look very similar and are hard to distinguish, especially juveniles. One way to distinguish them is by looking at the gill rakers. The lesser amberjack (S. fasciata) and the almaco jack (S. rivoliana) have 21-29 gill rakers that extend all the way to the point of attachment (see drawing). The greater amberjack and the banded rudderfish (S. zonata) have only 12-19 gill rakers, and the gill rakers do not extend to the point of attachment. The greater amberjack can be further distinguished from the banded rudderfish by the distinct broadly rounded hump (and corresponding dip) on the posterior dorsal end of its upper jaw (the supramaxilla). The banded rudderfish has a broadly rounded supramaxilla, but no hump. Margin is straight. The banded rudderfish has a smaller eye than other amberjacks. Its upper jaw extends to or past the middle of the eye. The greater amberjack's mouth extends to or before the middle of the eye. Also the banded rudderfish has a shorter anal fin base than other amberjacks (up to 2.1 times into dorsal fin base, others less than 2).
Habitat
Gulf and sometimes bay, associated with floating objects
Maximum Size
80 cm (31 1/2 in), common to 58 cm (23 in)
Fin Element Counts
D. VIII+I,33-40; A. II+I,19-21 (explain)
Other Common Names
Previous Scientific Names
Comments
State size/bag limits