According to Pindar, he and several other members of his family went to Iolcus to intercede with Pelias on behalf of Jason. Pausanias mentioned him among those to whom the restoration of the Olympic Games was ascribed. A part of Elis was thought to have been named Amythaonia after him.
Pindar, The Odes of Pindar including the Principal Fragments with an Introduction and an English Translation by Sir John Sandys, Litt.D., FBA. Cambridge, MA., Harvard University Press; London, William Heinemann Ltd. 1937. Greek text available at the Perseus Digital Library.
Stephanus of Byzantium, Stephani Byzantii Ethnicorum quae supersunt, edited by August Meineike (1790-1870), published 1849. A few entries from this important ancient handbook of place names have been translated by Brady Kiesling. Online version at the Topos Text Project.