Watch List notes:

Anonymous. Ca. 217-215 B.C. AE semuncia (21.18 mm, 6.91 g, 1 h). Semilibral standard. Rome mint. Head of Mercury right, wearing winged petasus / ROMA, prow of galley right. Crawford 38/7; Sydenham 87. aEF, blue-green patina, porous. 

Ex RBW Collection; Ex Tempestini. 

Overstruck?