One of the socially parasitic bumblebees formerly placed in the genus Psithyrus, which is now regarded as a sub-genus of Bombus. It is known to parasitise the nests of Bombus terrestris. The general distribution is more southerly than that of its look-alike, Bombus bohemicus, which matches the situation in the known hosts of these two species (B. lucorum is the host of B. bohemicus). This may be a species which is showing signs of distribution change due to climatic change. In view of the northward extension of distribution of several bumblebee species it will be interesting to see whether B. vestalis has also extended its range northwards. Both males and females can be suspected by the narrow yellow patches at the base of the white tail. These patches are generally more intense and extensive than in B. bohemicus, however, microscopic examination will be required to reliably separate the two species.
Widely distributed in England, Wales and south-east Scotland. Now distinctly uncommon on the Isles of Scilly (Beavis 2000). Overseas, the species occurs in much of Europe, although it is scarce in Scandinavia, occuring in the extreme south only. In Asia, it is found from the Caucasus to northern Iran.