In Greek mythology, Hypso, from Pellene in Achaea, was the mother of the Argonauts Amphion and Asterius (Deucalion [1] ) by Hyperasius, son of Pelles. [2] In some sources, the father of these men were Hippasus. [3] Hypso gave birth to her sons at one birth and she could not tell one apart from the other because of their likeness. [1] This suggests that they were identical twins.