The Atlantic horse mackerel is a fish with the dorsal part of its body darker than the ventail side, which is practically white. The eyes and mouth are large in comparison with the size of its body. The line that runs down the body from the head to the tail, the side line, is highly marked and presents a highly characteristic curve at the beginning. Its maximum size is 60 cm.
Atlantic horse mackerels are fish that swim in schools, sometimes large, at depths of 10 to 100 m, generally on the high seas. The adults feed on small schools of fish (herrings, sardines, etc.), crustaceans and cephalopods.The young feed on tiny larvae and crustaceans in the plankton; therefore it is a carnivorous animal.Its reproduction is oviparous and spawning (egg laying) takes place in the summer. Females lay 140,000 eggs, which hatch into 5mm long larvae .