Other Common Names
Eastern Evening Primrose-Sweat bee
Evening Primrose Sweat Bee
Synonyms and other taxonomic changes
Halictus (Evylaeus) oenotherae Stevens, 1920; Halictus ralenci Crawford, 1932; Lasioglossum (Evylaeus) oenotherae (Stevens, 1920); Lasioglossum (Evylaeus) ralenci (Crawford, 1932); Sphecodogastra oenotherae (Stevens, 1920)
Explanation of Names
Lasioglossum (Sphecodogastra) oenotherae (Stevens, 1920)
Female: 6.6-8.2 mm. Male: 7.3-8.1 mm
Head: Black, with short white hair. Lower face (clypeus) slightly projecting. Cheeks slightly wider than eye width. Mandibles long, small tooth.
Antenna: Base (scape) and segments brown. Underside of antennae more reddish.
Thorax: Black, shiny with sparse, white hair. Shoulder pads (humeri) and sometimes outer ends of collar have dense hair. Segment 3 (propodeum) has series of longitudinal ridges in both male and female which are unique in the Sphecodogastra. Thorax side tubercle dark with whitish fringe.
Wings: Wing knobs (tegulae) light brown. Wings slightly tinted. Veins pale brown; stigma and costa darker.
Legs: Dark brown with short, yellowish-white hair. Hind shin modified, thin with only one row of long hairs on inner side for collecting Evening Primrose Oenothera pollen. Spur also modified with teeth along length.
Abdomen: Dark brown, narrow, smooth and shiny with short, pale yellowish-white hair. Lower margins of all segments lighter in color. Segments 1 has hair only at side edges. Segment 2 has hair at side edges and a faint stripe along lower margin. Segments 3 to 5 may also have faint stripes along both base and lower margins.
Head: Long and black with sparse, short white hair, thicker on lower face. Lower face (clypeus) projecting with a large yellow transverse stripe across lower margin; another narrow yellow stripe (on labrum) below it. Mandibles short. Cheeks about equal to eye width.
Antenna: Base (scape) and segments brown, segments a bit lighter on underside. Segment 1 very short.
Thorax: Black with a thin covering of very short, whitish hair. Segment 1 has thicker hair on shoulder pads (humeri). Segment 2 (scutellum) has a deep median indent. Segment 3 (propodeum) has series of longitudinal ridges in both male and female which are unique in the Sphecodogastra. Thorax side has yellow tubercle.
Wings: Wing knob (tegulae) yellowish-brown; may have yellow spot. Wings lightly tinted. Veins and stigma pale reddish-brown.
Legs: Thighs (femora) black. Front shin (tibiae) yellow with dark patch on underside. Mid and hind shins dark with yellow base and tip. Feet yellow, tips dark.
Abdomen: Black, shiny with very short, thin whitish hair. Base of segments have faint line of whitish hair, sometimes hidden by segment overlap. Underside has wide mat of pilose hair at base of segments 2 to 4; 5 and 6 have long hairs.
Canada: Ontario to Nova Scotia. U.S.A.: along east coast to Georgia, west to Kansas and north to North Dakota.
Gardens with Evening Primrose Oenothera. Apparently the bee has not been found on wild populations of Evening Primrose, but prefers domestic gardens instead.
May to August
Mid-June to late August in Ontario.
. The Hosts section on its Discover Life species page
lists known floral associations based on specimen records and images.
Generally Sphecodogastra females over-winter and build many nests together in sandy, stony areas. Each nest contains clustered cells near the surface with 12 to 20 cells each. New adults appear about 45 days later and mate. Males die off and females hibernate in deeper tunnels of the nest. One generation per year in north. Possibly two generations in the south.
Holotype as Halictus (Evylaeus) oenotherae female by Stevens. Type #12033 and #23848. Locality: Blue Rapids, Kansas, June 20, 1919. In the U. S. National Museum of Natural History, Smithsonian.
Holotype as Halictus ralenci female by Crawford. #33827. Locality: Raleigh, North Carolina May 29, 1924 by C.S. Brimley. In the American Museum of Natural History, New York.
The Pan-Pacific Entomologist, 1962, Vol. 38, pg. 45 by Linsley & MacSwain.
The Canadian Entomologist, 1964, Vol. 96, pp. 958 to 959 by Knerer & Atwood.
Canadian Journal of Zoology, 1969, Vol. 47, pp. 289-294: Bionomic Notes on the Solitary Evylaeus oenotherae by Knerer and MacKay.
Gibbs, J., Packer, L., Dumesh, S., & Danforth, B. N. (2013). Revision and reclassification of Lasioglossum (Evylaeus), L. (Hemihalictus) and L. (Sphecodogastra) in eastern North America (Hymenoptera: Apoidea: Halictidae). Zootaxa, 3672(1), 1. https://doi.org/10.11646/zootaxa.3672.1.1(1)
Entomological News, 1920, Vol. 31, pp. 37 to 38 by Stevens.
Proceedings of the Entomological Society of Washington, 1932, Vol. 34, #5: New North American Bees by Crawford, pp. 69 to 70.
North Carolina Agricultural Experiment Station, 1962, Technical Bulletin #152: Bees of the Eastern United States by Mitchell. [male as Evylaeus truncatus]
Smithsonian Contributions to Zoology, 2003, #610: Studies of Halictinae II: Revision of Sphecodogastra by McGinley, pp. 40 to 44.