This small, 16mm provincial coin is strange and doesn't ring any bells. Obverse says "AVT---DIANOS"(?) with bare head right. Reverse "D--POL--" with a centaur(?) advancing left. I can't even begin to a guess. The only emperor I can think of with -DIANO- would be Gordian, but I don't see any examples even close in Wildwinds.
I like Gordian here's one possibility: MESOPOTAMIA, Singara. Gordian III. AD 238-244. Æ 19mm (7.47 g, 7h). Laureate, draped, and cuirassed bust right, seen from behind / Centaur (Sagittarius) advancing right, shooting arrow; in background, vexillum inscribed ΛЄ/Γ in two lines. BMC -; SNG Copenhagen -; SNG Hunterian -; cf. Lindgren & Kovacs 2625; Mionnet suppl. VIII 81. Near VF, mottled red and brown patina. From the J.S. Wagner Collection.
Not a centaur. The coin is from Hadrianopolis, Gordian III, reverse Eros on dolphin. This example might be a die match: https://rpc.ashmus.ox.ac.uk/coin/346193