Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada

Species Bombus sonorus - Sonoran Bumble Bee

Sonoran Bumble Bee? I think so. - Bombus sonorus bumble bee - Bombus sonorus - female Balboa bumble bee - Bombus sonorus Sonoran Bumble Bee - Bombus sonorus Bombus sonorus? - Bombus sonorus Bombus sonorus? - Bombus sonorus Bombus sonorus Bombus sonorus - female
Classification
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 (Apoidea (clade Anthophila) - Bees)
Family Apidae (Cuckoo, Carpenter, Digger, Bumble, and Honey Bees)
Subfamily Apinae (Honey, Bumble, Longhorn, Orchid, and Digger Bees)
Tribe Bombini (Bumble Bees)
Genus Bombus (Bumble Bees)
No Taxon (Subgenus Thoracobombus)
Species sonorus (Sonoran Bumble Bee)
Synonyms and other taxonomic changes
Often treated as a subspecies of Bombus pensylvanicus
Explanation of Names
Bombus sonorus Say, 1837
Size
Large
Identification
Similar to the very closely related pensylvanicus, but in sonorus the dorsum of the thorax is yellow posteriorly and there is a distinct black interalar band, whereas in typical pensylvanicus the dorsum of the thorax is largely or entirely black posteriorly. Unlike B. fervidus, T4 of females is black.
Range
sw US (s. CA to c. TX, s. NV-sw. UT) / to s. Mex. (1), Widespread in southern California but more local in northern California where best known from the Central Valley and adjacent valleys in the foothill zone (see below for status). The common bumble bee of the Sonoran and Chihuahuan deserts.
Habitat
Mostly low elevations including deserts and cultivated valleys.
Season
Feb-Oct (BG data)
Food
Strongly associated with sunflowers (Helianthus annuus) but also visits many other plants, notably nightshades (Solanum) and globe mallows (Sphaeralcea). The Hosts section of its Discover Life species page lists known floral associations based on specimen records and images.
Remarks
Has declined severely in its northern California range and no longer detected at sites where it was abundant in the 1990s. Still regularly found in the Sonoran and Chihuahuan deserts but number vary greatly between years depending, reflecting in part availability of its favorite host plants whose bloom depends on irregular rainfall.
Texas considers this a "Species of Greatest Conservation Need" (SGCN) (2)
Internet References
Info - Map - Discover Life