Bombus barbutellus

Bombus barbutellus, or Barbut's cuckoo-bee, is a species of cuckoo bumblebee, widespread, if not especially common, in most of Europe.

Description

The species is a medium-length bumblebee with a body length of for the female and for the male. The collar and the top of the head are yellow, the scutellum has yellow hairs, and the first tergite is usually more or less yellow. The tail is whitish; the last tergite of the male, however, has intermixed black hairs. The rest of the fur, which is quite short, is black.

Ecology

As a cuckoo bumblebee, B. barbutellus does not build any nest of its own, but usurps the nests of other bumblebees, killing the queen and forcing the workers to raise its own offspring. The main hosts are B. hortorum, B. ruderatus, and B. argillaceus.
Favourite food sources are flowering plants such as thistles; the queen also visits white deadnettle and vetches, while the male feeds on bramble, knapweed, lavender, and honeysuckles.

Distribution

Bombus barbutellus is widely distributed, if not particularly common, in most of Europe from the middle of Fennoscandia in the north to southern Spain, and from the British Isles in the west to easternmost Russia. In Britain, its major distribution is in southern England, East Anglia, and western Wales.