Philip II and Serapis. AE26 of Mesembria, Thrace. AD 247-249.

M AR IOYLIOC FILIPPOC KAICAR, bare-headed, draped and cuirassed bust of Philip II right, facing bust of Serapis left, wearing modius. 
MECAMBRIANWN, emperor on horseback riding right, holding sceptre and raising right hand.

Varbanov 4287; Moushmov 4038; Berlin 18250026 (this coin).

Image courtesy of the Berlin cabinet, ikmk.smb.museum.