Watch List notes:

Philip I. AD 244-249. AR Antoninianus (22mm, 3.63 g, 12h). Antioch mint. 1st emission, AD 244-245. IMP IVL PHILIPPVS PIVS FEL AVG, P M below bust, radiate, draped, and cuirassed bust right / PAX FVND ATA CVM PERSIS, Pax standing left, holding olive branch and transverse scepter. RIC IV 72; RSC 114. Good VF, lightly toned. Rare. Unusual placement of P M in obverse legend.

The 'P M' under the bust does not mean 'pontifex maximus', but 'Persicus Maximus', 'greatest of Persian conquerors'. The reverse also celebrates peace with the Persia.