(Ἴων), of Thessalonica, was an officer of Perseus, king of Macedonia, and commanded, with Timanor, his light-armed troops in the battle in Thessaly, in which the Romans were defeated, B. C. 171. In B. C. 168, after Perseus had been conquered at Pydna, Ion delivered up at Samothrace to Cn. Octavius (the commander of the Roman fleet) the king's younger children, who had been entrusted to his care. (Liv. 42.58, 45.6.)
[E.E]A Dictionary of Greek and Roman biography and mythology
Smith, William
A Dictionary of Greek and Roman biography and mythology. William Smith, LLD, ed. 1890