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Echemus
In Greek mythology, Echemus (, Ekhemos) was the king of Arcadia. He succeeded Lycurgus, and married Timandra, daughter of Leda and Tyndareus of Sparta.
Timandra bore him a son, Laodocus, before deserting Echemus for Phyleus, the king of Dulichium.
After the death of Eurystheus, Hyllus led the Heracleidae to attack Mycenae. Echemus offered himself as the champion of the defending Arcadian forces and killed Hyllus in single combat, thus forcing the Heracleidae to withdraw. This story is mentioned by the Tegeans as an example of their people's bravery in book 9 of The History by Herodotus.