Actually, most dione don't look a lot like bimaculata. The Chinese dione look like them. You kinda have to see the whole picture. After working with both, they are now pretty easy to tell apart. The dione have a stronger tendency towards stripes, but the most obvious thing is their behavior. Bimaculata is more secretive and usually tries to hide, more fossorial. Look at head shapes too. Dione is more diurnal and active. They are a lot like the Russians in that they are more visible, especially during the day. Hope this helps some. TC.