|Atlantic Chub Mackerel
Unique Characters: Two small keels on either side of caudal peduncle. 5 dorsal and 5 anal finlets. Adipose eyelids cover front and rear of eye. Blue dorsally, fading to silvery below. Back and upper sides with many oblique, faint to dark wavy lines; lines break into dusky spots around midline. Eyes comparatively large. Dorsal fins separated by distance about equal to dorsal-fin base.
Similar Species: All other Scombrids, except Scomber scombrus, Atlantic Mackerel, have two small keels and a large median keel between them on either side of caudal peduncle. 7-10 dorsal and 7-10 anal finlets. Adipose eyelids absent.
Atlantic Mackerel Scomber scombrus. Two small keels on either side of caudal peduncle. 5 dorsal and 5 anal finlets. Adipose eyelids cover front and rear of eye. Iridescent dark blue dorsally, becoming greenish to about midline; silvery below. Upper sides with many oblique wavy lines. A broken dark stripe usually present along midline. Eyes comparatively small. Dorsal fins separated by a distance greater than the length of the first dorsal fin.