In Greek mythology, Themisto , daughter of Hypseus, was the third and last wife of Athamas. According to some sources, she had four children by him: Leucon, Erythrius, Schoeneus, and Ptous. In other sources there were but two: Sphincius and Orchomenus, or else Schoeneus and Leucon. Some say that the father of Leucon was Poseidon (see also Leuconoe).