Bloody-nosed beetle

Timarcha is a difficult genus, with a lot of very similar, poorly-defined species on the Balkan Peninsula, whose distribution is poorly understood. Some of them may turn out to be synonyms in future. For your beetle here, the possibilities are: T. goettingensis, T. pratensis, T. durmitoriensis, T. stepaneki and T. montana. I think that T. goettingensis is most likely, because of the relatively fine elytral sculpture, but I can't be sure.