NOT IN RIC
UNLISTED FOR RULER. RIC lists similar issue from Nicomedia minted for Constantius II only (NICOMEDIA 187 and unlisted NICOMEDIA [before 187] (p. 633).
Note that reverse with three palm branches is attested for three Caesars (Crispus, Constantine II and Constantius II) and five mints (Rome, Ticinum, Thessalonica, Nicomedia and Antioch), but dating of these issues in RIC is inconsistent and disputable. According to RIC ROME 379 and 380 (p. 343, Constantius II and Constantine II) were struck in 336-7; TICINUM 184 (p. 383, Constantine II) was struck in 324-5; THESSALONICA 195 (p. 526, Constantine II) was struck in 335; NICOMEDIA 187 (p. 633, Constantius II) was struck in 336-7 and ANTIOCH 70A (p. 720 ["Addenda and Corrigenda"], Crispus) was struck no later than 326. Presence of Crispus' coins (ANTIOCH 70A and unlisted NICOMEDIA [before 117]) suggests rather earlier date, c. 325. Repetition of the same reverse type on the new issues after 10 years is possible, however, seems to be a weaker hypothesis.
Note also that Constantine II looks very young. Coin should be listed before NICOMEDIA 117.
ROME [after 379], CONSTANTIUS II, UNLISTED BUST TYPE AND REVERSE LEGEND
NICOMEDIA [before 117], CRISPUS, UNLISTED FOR RULER
NICOMEDIA [before 187], CONSTANTIUS II, UNLISTED REVERSE LEGEND