The common dolphinfish has a tapering body compressed at the sides. Its dorsal fin is very long, almost mane-like. The back is green and the sides silver, with small brown and blue spots. The colouring in the young is brighter and more marked. Its small scales are tucked into the skin, so much so as to seem inexistent. The male adults have a small hump on the head. They can reach 2m in length, although in general they don’t exceed 1m.