Megareus (son of Poseidon)

In Greek mythology, Megareus (Ancient Greek: Μεγαρέας or Μεγαρέως, lit.'man from Megara' or 'inhabitant of Megara'), also called Megarus (Μέγαρος), was king of Onchestus in Boeotia. In some myths, he was the eponymous king of Megara.