Bombus (Psithyrus) quadricolor
(Lepeletier, 1832)
Bombus quadricolor lives from the Pyrenees and the Cantabrian to the South to the middle of Fennoscandia to the North. Its Oriental limit is not well known, likely in the Altai. To the West, it barely reaches the Atlantic coast, being absent from UK. It shows several subspecies with a somewhat intricated distribution and unclear status. It inquilines B. soroeensis.
P. Rasmont