Marcus Aurelius, AE24 of Philadelphia, Lydia, 7.10g. AD 161-162. 

AYT K M AYR ANTWNEINOC, bare head right
EPI LADI CEB HROY ARXO FILADELFEWN, serpent-entwined omphalos. 

ANS 1944.100.49357; RPC online 3556.

Ex Gorny & Mosch, auction 200, lot 2181.