Septimius Severus 193 - 211 AD. AR Denarius AD 209. Rome. 

SEVERVS PIVS AVG, laureate head right.
P M TR P XVII COS III P P, Neptune, naked except for cloak 
over left shoulder and right arm, standing left, right foot 
on rock, right hand on right knee and holding vertical trident.

BMCRE 3; RSC 529; RIC 228.

With permission of cngcoins.com, AK Collection sale, 97.