Constantius II, AE3 of Rome.

DN CONSTAN-TIVS PF AVG, laurel and rosette-diademed, draped, cuirassed bust right.
FEL TEMP-REPARATIO, soldier spearing fallen horseman who is 
reaching backwards, hair straight up.
Mintmark RQ.

RIC VIII Rome 272 var (bust type and horseman's hair).

Dane's collection, Jan. 2016.