Jehoshaphat (high priest)

According to Seder Olam Zuta, Jehoshaphat was a High Priest of Israel, succeeding Jehoiarib and succeeded by Jehoiada. Josephus does not mention a Jehoshaphat and according to Josephus the second High Priest after Joram (chronological place of Jehoshaphat) was Pediah. Jehoshaphat is also never mentioned in the Tanakh and his name doesn't appear in the list of the Zadokite dynasty (1 Chr. 5:30-40, 6:4-15 in other translations).