Bombus appositus
Cresson, 1879
White-shouldered Bumble Bee
Bombus appositus, the white-shouldered bumblebee, is a western North American found in open from southwestern Canada through the Cascade Mountains and Sierra Nevada to central California. It nests underground or on the surface and has been documented feeding on diverse floral resources including giant hyssops, thistles, gentians, and clovers. The species is known to be a for the cuckoo bumblebee Bombus insularis.



Pronunciation
How to pronounce Bombus appositus: //ˈbɔm.bʊs əˈpoʊ.sɪ.təs//
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Images
Habitat
Open including meadows and slopes. Nests are constructed underground or on the surface.
Distribution
Western North America: southwestern Canada south through the Cascade Mountains and Sierra Nevada to central California, and west to central California.
Diet
Feeds on a variety of plant including giant hyssops (Agastache), thistles (Cirsium), gentians (Gentiana), owl's clovers (Castilleja), locoweeds (Oxytropis), penstemons (Penstemon), and clovers (Trifolium). Has been observed to especially favor subalpine larkspur (Delphinium barbeyi) and serves as one of its main .
Behavior
Males congregate in groups to seek mates.
Ecological Role
of diverse native plants including Delphinium barbeyi. to the cuckoo bumblebee Bombus insularis, which parasitizes its nests.
Similar Taxa
- Bombus insularisCuckoo bumblebee that parasitizes Bombus appositus nests; can be distinguished by its parasitic lifestyle and lack of .
Sources and further reading
- BugGuide
- Wikipedia
- GBIF taxonomy match
- iNaturalist taxon
- NCBI Taxonomy
- Catalogue of Life
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