Scientific Name: Lasioglossum cressonii (Robertson, 1890)

Common Name: Cresson s Sweat Bee


Halictus Cressonii Robertson, 1890: 317 [♀,♂‚]

     Lectotype ♀ [designated by Gibbs 2011: 79]. USA, Massachusetts [ANSP no. 4253]

Halictus (Chloralictus) cressoni Viereck, 1916: 707 [unnecessary emend name]

Dialictus delectatus Mitchell, 1960: 435 [♂‚] [synonymy by Gibbs 2010: 101]

     Holotype ♂‚. USA, Maryland, Plummer’s Is., 13 September 1958, by K.V. Krombein [USNM no. 66072]


Species Notes

This is the type species for the genus-group name Chloralictus.

Gibbs (2011) designated the lectotype above to ensure stability in the application of the name as a specimen of L. achilleae also occurs in the syntype series.

The DNA Barcode Index Numbers (BINs) for this species in Canada are BOLD:AAA5973, BOLD:AAA5974, BOLD:ABY7290, and BOLD:ACE7675. Gibbs (2010) indicated that the patterns in DNA barcoding are not related to geography as specimens collected at the same time and location may have different DNA barcode haplotypes. In addition, morphological comparisons failed to yield corresponding anatomical characters consistent with unique BINs. However, the barcodes do not give a pattern of paraphyly (i.e. no other species arise within the larger cluster), so DNA barcoding should still be possible.



♀ body length: 5.19–6.80 mm; head length: 1.46–1.75 mm; head width: 1.49–1.82 mm; forewing length: 3.97–5.49 mm

♂‚ body length: 5.12–6.30 mm; head length: 1.61–1.70 mm; head width: 1.54–1.70 mm; forewing length: 3.97–4.58 mm



This species is eusocial like most other Lasioglossum, subgenus Dialictus. Gibbs (2010) indicated that this species was common in Canada. Sakagami and Michener (1962) dicuss the nesting biology of this species. Mitchell (1960) also indicated it will nest in rotten wood (Mitchell 1960).


Extent of Occurrence (EOO) in Canada (http://geocat.kew.org/): 2,801,887 km2

Index of Area of Occupancy (IAO) in Canada (http://geocat.kew.org/): 736 km2



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

Mitchell TB (1960) Bees of the Eastern United States. Volume 1. North Carolina Agricultural Experiment Station Technical Bulletin 141: 1-538.

Robertson C (1890) New North American bees of the genera Halictus and Prosopis. Transactions of the American Entomological Society 17 (4): 315‑318. URL: http://www.jstor.org/stable/25076547

Sakagami SF, Michener CD (1962) The Nest Architecture of the Sweat Bees (Halictinae), a Comparative Study of Behavior. The University of Kansas Press, Lawrence, Kansas [v]+ 135 pp.

Viereck HL (1916) The Hymenoptera, or wasp-like insects of Connecticut. Connecticut State Geological and Natural History Survey Bulletin 22: 1–824.


Sociality: Presumed Eusocial
Nesting: Rotting Wood Excavator
Pollen Specialization: Polylectic
Wintering Stage: Mated Female

Crop Preference: Not Available
Non Crop Preference: Vaccinium angustifolium

Distribution: Alberta, British Columbia, Manitoba, New Brunswick, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan
Ecozone: Atlantic Maritime, Boreal Plains, Boreal Shield, Hudson Plains, Mixwood Plains, Montane Cordillera, Pacific Maritime, Prairie, Western Interior Basin

Distribution Map