Ptolemy I of Telmessus, or Ptolemy Epigonos, (299/298 BC–February 240 BC) was a Greek Prince from Asia Minor who was of Macedonian
and Thessalian descent. He was the son of Lysimachus and Arsinoe II. After failing to ascend the throne of the Kingdom of
Macedonia, he fled to Egypt, where he ruled as co-regent with Ptolemy II from no later than 267 B.C. until 259 B.C. He was
sent to Miletus, where he revolted against Ptolemy II in 259/258, but reconcilated. He then ruled as client-king of the Ptolemaic
Empire in Telmessus from 258 to 240 B.C.