The Russian honeybee is basically a Carniolan whose range overlapped the mites for a hundred years or so.
One of my new hives are Russians. They where started as a nuc. Our Russians are extremely gentle and fly at cooler temps than our other bees. We had temps that where about 20 degrees below normal for a few days last week, and the Russians would be flying out flying well before our other bees. I have only had them for two weeks.
Russians and Carniolans are both known swarmers.
Shane