The author during 1964-1989 has been investigating bumble – bee fauna in Caucasus. The existence of 48 types of bumble bees and cuckoo-bumble bees was established. The investigation showed that bumble bees were dwelling in the great majority of Caucasus isthmus, but not in the eastern foot of Caucasus (Cuma-Tersk and Kura-Araks lowland and lengthwise of the middle stream of the river Araks (The Djulpha region).

For the first time are named 5 main zoogeographical districts of bumble bee's dwelling in the Caucasus. They are: 1. The region of Great Caucasus range of the western part of Daghestan and minor Caucasus; 2. The Region of Djavakheti and Armenian uplands; 3. The Region of the foot of Caucasus, Eastern and Inner Daghestan, Eastern Georgia and western Aperbaidjan; 4. The region of Rioni lowland; 5. The Region of Lenkoran and Talish. The main diversity of Caucasus bumble bees Fauna is concentrated in two zoogeographic regions: in Great and Minor Caucasus and in the Armenian upland. This region is characterized by a great endemism of bumble bee's faunas.