Lysimachos, King of Thrace. AE18mm. 

Obv: Laureate head of Zeus right.
Rev: LY above horseman right, forepart of lion right, below.

cf Mionnet 1, 121 (silver); ACA 3737.

Ancient coin Art, item 3737, 2003. 
Found in an orphaned "Mystery" folder and added August 2010.