I think dichroa for sure. I`ve never seen rubra from Far East. The distribution is restricted by the Altai Mountains in my view. rubra: pronotum with clear oblique notches at the posterior corners the body is relatively short and wide, thick (in large females especially) the males are black with yellow elytra and (partly) tibias, females are red. dichroa: pronotum without notches at the posterior corners males and females are red with dark legs (males have reddish tibia usually) Females have elongated elytra strongly narrowed toward apex
Some variability is present in both cases. But it is not the same species.