Watch List notes:

Caracalla. AD 198-217. AR Antoninianus (24mm, 4.79 g, 12h). Rome mint. Struck AD 217. Radiate and draped bust right / Serapis standing facing, head left, raising hand and holding scepter. RIC IV 289d var. (holding wreath); RSC 383b var. (same). Good VF, light scratches, minor porosity.

This reverse type with Serapis standing facing, head left, and raising his right hand appears to be unpublished in RIC and RSC for TR P XX.