the Scythians, settled at that time in both the Crimea and in Dobrogea,
****GK: I.e. at the time of the Diophantos campaigns (110-108 BCE). That is actually the only portion of your objection worth discussing. Namely, when did the Scythians lose political control of "Little Scythia"? And how does the arrival of the Bastarnae relate to this (if it does)? A starting point would be the newly discovered Skilur inscription at Neapolis which affirms that c. 120 BCE his empire stretched "from the Thracians to the Maeotians".****