Sea scorpions and true scorpions are actually sister clades that both belong to a Subphylum known as Chelicerata, an ancient group of arthropods that first appeared in the oceans of the Cambrian Period.

海蝎子和真蝎子实际上是姊妹进化枝， 都属被称为螯肢亚门的亚门，这是一种最早出武纪海洋中的古老节肢群。