Elongate, cylindrical, slender, its depth 4.5- 5.0 in SL; mouth opens at front, reaches almost under center of eye; gill rakers at angle of 1st gill arch very short, overlapped by longer upper rakers; lower part of gill cover with bony ridges radiating obliquely down; dorsal fin 14, at about midbody; pelvics under rear of dorsal; anal fin with short base, 17, origin well behind dorsal; ridge of keeled scales along belly.
Blue on back, silvery on sides, and white on belly; widely scattered blackish spots on side.
Size: grows to about 41 cm.
Depth: 0-200 m.
Habitat: pelagic in coastal waters.
In the north from Alaska to Gulf of California, and the Revillagigedos; in the south from southern Ecuador to Chile, and the Galapagos.
A recent genetic analysis (Grant et al. 1998) of the status of Sardinops populations indicates that there are three subspecies: S. s. ocellatus from south Africa, Australia and New Zealand, S. s. sagax from the southern and northern eastern Pacific, and S. s. melanostictus from the northwest Pacific.