Bombus (Alpinobombus) polaris
Ross, 1935
The overall range of Bombus polaris is circumboreal (K.W. Richards, 1973). This distribution reminds of that of balteatus, while being more arctic: the species is restricted to the strictly arctic milieu. In N. America, it stays north of the 60th parallel, except in a few places in Labrador, on the Hudson Bay and in Quebec, but always beyond the tree-line. It is also found in the islands islands : on Baffin and Ellesmere, and even on the far north of Greenland, i. e. well above the 80° N.
In continental Russia and Siberia, it is restricted to the coast of the Arctic Ocean. It is also present on Novaia Zemlia, Wrangel and some other Siberian islands (Berezin 1995). As in Greenland, polaris can be found up to the 83rd parallel.
Bombus polaris is subject to inquilinism from B. hyperboreus, but this species is generally rarer and still more restricted to the colder regions.
P. Rasmont