This coin is either unofficial or fake. It is struck and the deposits are pretty convincing, but the style reminds me of too many fakes; but I can't recall ever seeing this one before.
Otacilia Severa
A.D. 244- 249
Antoninianus
21mm 4.5g
M OTACIL SEVERA AVG; diademed and draped bust right, on crescent.
IVNO CONSERVAT; Juno standing left, patera in right, long scepter vertical in left.
Cf. RIC IV Rome 127