Watch List notes:

CARIA. Chersonesos. Circa 480-450 BC. Diobol (Silver, 11 mm, 1.49 g, 6 h). Forepart of a winged boar to left. Rev. +ΕΡ Bull's head facing; all within an incuse square. Cahn X25. HN Online 563. SNG Ashmolean 51. Very rare. Well-struck and toned. Obverse very slightly off-center, otherwise, good very fine.
From the "Collection sans Pareille" of Ancient Greek Fractions, ex Münzen und Medaillen FPL 602, November/December 1996, 83.