Subgenus Pyrobombus

These could be called the Fiery-tailed Bumble Bees

Pyrobombus Dalla Torre 1880

19 spp. in our area, 50 total(1)

Relatively small, especially the workers

Midleg with rounded angle. The faces and malar space are variable in length but tend to be intermediate between the Cullumanobombus (shorter) and the Thoracobombus (longer). The hair coat of many species is relatively long and shaggy but less so than in Alpinobombus. Eye of male normal (not enlarged)

Species identification is often difficult, as their are many similar species that mimic each other.

holarctic group; ~30 spp. are in the Palaearctic; in our area, all 19 spp. occur in the US, 17 also in Canada, 2 range into Mexico (there are 2 more spp. in Mexico & C.America to Panama)(1) The subgenus is particular common in temperate climates and less well represented in xeric or truly boreal regions.

Mountain-meadow, forest, grassland, semi-desert, and tropical montane forest(2)

Flight season typically long. Queens of many species emerge early. Some such as bimaculatus and perplexus produce reproductives in summer and end activity soon after, whereas other species such as impatien persist until very late fall.

Floral associations diverse and variable depending on tongue length. This subgenus includes some of the most important pollinators of crops such as apples and blueberries.

Nests underground or on the surface(2)

This subgenus includes some of the most common species. Most seem to be persisting or even increasing unlike species in other subgenera such as Bombus (Bombus) that have declined severely.

Most orange-banded bumble bees belong to this subgenus (B. rufocinctus is the exception)