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Species Bombus insularis - Indiscriminate Cuckoo Bumble Bee

Bumble Bee and Dandelion - Bombus insularis Bumble bee - Bombus insularis Bombus vosnesenskii male? - Bombus insularis - male Bombus for ID - Bombus insularis Bee on Helianthus annuus.   - Bombus insularis - male Bombus  - Bombus insularis Bombus - Bombus insularis Bombus suckleyi queen? - Bombus insularis - female
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata - Ants, Bees and Stinging Wasps)
No Taxon (Anthophila (Apoidea) - Bees)
Family Apidae (Cuckoo, Carpenter, Digger, Bumble, and Honey Bees)
Subfamily Apinae (Honey, Bumble, Long-horned, Orchid, and Digger Bees)
Tribe Bombini (Bumble Bees)
Genus Bombus (Bumble Bees)
No Taxon (Subgenus Psithyrus)
Species insularis (Indiscriminate Cuckoo Bumble Bee)
Synonyms and other taxonomic changes
formerly placed in Psithyrus, which is now considered a subgenus of Bombus - see links below
Explanation of Names
Author: Smith, 1861.
Female: 16-19 mm. Male 13-16 mm.
Commonly encountered in Canada and forested areas of the western United States, but rarely found in the northeastern United States where restricted to northern and montane sites
May to August.
Social parasites of other bumble bees. Both sexes regularly visit flowers for nectar including composites. The Hosts section of its Discover Life species page lists known floral associations based on specimen records and images.
Print References
Michener, Charles D. 2007. (2nd ed.) The Bees of the World. 1,016 pp. Johns Hopkins University Press. [advertised here]
Internet References
12 pinned adult images (
common name reference; PDF doc (Committee on Common Names of Insects, Entomological Society of America)
discussion on subgenus Psithyrus plus list and distribution of world species (Natural History Museum, UK)
world bee genera plus synonyms and subgenera; list based on Michener, 2000 (Doug Yanega, U. of California at Riverside)