Watch List notes:

MYSIA. Kyzikos. Circa 500-450 BC. Stater (Electrum, 22 mm, 15.88 g). Double-bodied sphinx, with a facing head and two bodies in profile, seated on a tunny swimming to left. Rev. Quadripartite incuse square. BMFA -. Cf. Greenwell 101 (hekte). Cf. SNG BN 280 (hekte). Cf. von Fritze 128 (hekte). Extremely rare. An impressive coin with a remarkable frontal representation, perfectly centered and nicely toned. One of the finest of the few examples known. Extremely fine.
From a European collection, ex Roma XIV, 21 September 2017, 221.