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Lasioglossum occidentale (Crawford, 1902)


Scientific Name: Lasioglossum occidentale (Crawford, 1902)

Common Name: Western Sweat Bee


Halictus anomalus Cockerell, 1901: 126. Misidentification, not Halictus anomalus Robertson, 1892.

Dialictus occidentalis Crawford, 1902: 318 [♀].

     Holotype . USA, New Mexico, Las Vegas, 4 July [no year provided], by T.D.A. Cockerell [USNM no. 3406].

Dialictus Theodori Crawford, 1902: 318 [♀]. Synonymy by Gibbs (2010: 220).

     Holotype ♀. USA, New Mexico, Las Vegas, 29 May 1902, by P. Hitchcock, on Convolvulus incanus [ANSP no. 10091].

Halictus galei Cockerell, 1919: 272 [♀]. Synonymy by Sandhouse (1923: 194).

     Holotype ♀. USA, Colorado, Gold Hill, 12 July 1919, by T. Cockerell and W. Cockerell [USNM no. 40261].


Taxonomic notes: The ♂ was keyed by Sandhouse (1923: 193) but described in full by Gibbs (2010: 221). The type material of Dialictus occidentalis Crawford, 1902 was taken from material originally identified by T.D.A. Cockerell as H. anomalus Robertson.

DNA Barcode Index Number (BIN): BOLD:AAC7155

Biology: Reported as a visitor of cactus (Opuntia) flowers by Hunter et al. (1912).

Distribution in Canada: Gibbs 2010 [AB, SK, MB]; Sheffield et al. 2014 [AB, SK, MB]; Woodcock et al. 2014 [ON; likely L. anomalum (Robertson, 1892)]; Gibbs et al. 2023 [MB].



Body length: ♀ 4.1 - 5.7 mm ♂ 5.1 mm

Forewing length: ♀ 3.4 - 3.6 mm ♂ 3.2 mm


Cockerell TDA (1919) The bees of Gold Hill, Colorado. The Canadian Entomologist 51(12): 271-273.

Crawford JC (1902) The bee genus Dialictus. The Canadian Entomologist 34(12): 318.

Gibbs J (2010) Revision of the metallic species of Lasioglossum (Dialictus) in Canada (Hymenoptera, Halictidae, Halictini). Zootaxa 2591: 1-382.

Sandhouse GA (1923) The bee-genus Dialictus. The Canadian Entomologist 55(8): 193-195.

Sheffield CS, Frier SD, Dumesh D (2014) The bees (Hymenoptera: Apoidea, Apiformes) of the Prairies Ecozone, with comparisons to other grasslands of Canada. In: Giberson DJ, Cárcamo HA (Eds) Arthropods of Canadian Grasslands (Volume 4): Biodiversity and Systematics Part 2. 4. Biological Survey of Canada, Ottawa, 479 pp. [ISBN 978-0-9689321-7-9].

Woodcock T, Pekkola L, Dawson C, Gadallah F, Kevan P (2014) Development of a Pollination Service Measurement (PSM) method using potted plant phytometry. Environmental Monitoring and Assessment 186(8): 5041-5057.

Gibbs J, Hanuschuk E, Miller R, Dubois M, Martini M, Robinson S, Nakagawa P, Sheffield CS, Onuferko T (2023) A checklist of the bees (Hymenoptera: Apoidea) of Manitoba, Canada. The Canadian Entomologist 155: E3.

Cockerell TDA (1901) Contributions from the New Mexico Biological Station. —X. Observations on bees collected at Las Vegas, New Mexico, and in the adjacent mountaions. Annals and Magazine of Natural History, Series 7 7(37): 125-134.

Hunter WD, Pratt FC, Mitchell JD (1912) The principal cactus insects of the United States. Bulletin of the United States Department of Agriculture Bureau of Entomology 113: 1-71.

Sociality: Presumed Eusocial
Nesting: Ground
Pollen Specialization: Polylectic
Wintering Stage: Mated Female

Crop Preference: Not Available
Non Crop Preference: Not Available

Distribution: Alberta, British Columbia, Manitoba, Saskatchewan
Ecozone: Pacific Maritime, Prairie

Distribution Map