Watch List notes:

Troas, Skepsis. ca. 197-188 B.C. Æ 12 (12.1 mm, 1.48 g, 6 h). Rare variety. Forepart of Pegasos flying right / Σ-K, Fir tree within linear border; thunderbolt to left, harpa to right. cf. SNG Cop 473 corr. (harpa not described); cf. SNG München 326; cf. SNG von Aulock 7950 var. (without thunderbolt). VF. 

This coin is a variation of the references cited. The coins cited are all 7-8 grams, much larger than this example. The thunderbolt and harpa do not seem to be recorded for the smaller series.