who succeeded as the ruler after him?
Archeptolis
Themistocles
Archeptolis, son of Themistocles, became a Governor of Magnesia after his father's death c. 459 BCE. Archeptolis also minted his own silver coinage as he ruled Magnesia, 
who was themistocles and what did he do He was an Athenian politician and general who convinced the polis to increase the naval power of Athens. is his portrait found in any money belonging to that period? Yes, he was probably the first ruler ever to issue coinage with his personal portrait. any known descendants? UNANSWERABLE
wiki:19675826
Themistocles [SEP] Succession and descendants
Archeptolis, son of Themistocles, became a Governor of Magnesia after his father's death c. 459 BCE. Archeptolis also minted his own silver coinage as he ruled Magnesia, and it is probable that part of his revenues continued to be handed over to the Achaemenids in exchange for the maintenance of their territorial grant. Themistocles and his son formed what some authors have called "a Greek dynasty in the Persian Empire". From a second wife, Themistocles also had a daughter named Mnesiptolema, whom he appointed as priestess of the Temple of Dindymene in Magnesia, with the title of "Mother of the Gods".