Reprinted with permission of the American Entomological Society from:
LaBerge, W. E., Ribble, D. W. 1975. A revision of the bees of the genus Andrena of the Western Hemisphere. Part VII. Subgenus Euandrena. Transactions of the American Entomological Society 101: 371-446.
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This small metallic species is similar to dissimulans but can be distinguished from the latter by its greenish-blue to blue metallic reflections, longer facial quadrangle, usually paler vestiture with dark scopal hair in the female, and shinier integument as described below. The male is very similar to males of suavis but the form of the tergal bands and sternal fimbriae and the more punctate propodeum will distinguish venata from suavis. The female seems similar to the female of nigrocaerulea in the simple, dark scopal hairs and the shiny clypeus, but differs in the generally paler vestiture and the narrower vannal lobes of the hind wings.
FEMALE. MEASUREMENTS AND RATIOS. — N = = 1; length, 10 mm; width, 3 mm; wing length, 3.60 mm; FI./FW, 1.07; FOVL/FOVW, 4.11.
INTEGUMENTAL COLOR. — Black with bright, slightly greenish, blue metallic reflections on terga (except apically), thorax and head (except clypeus) except as follows: mandible rufescent in apical half; face rufescent adjacent to clypeal margin; terga rufescent basal to apical areas; sterna dark rufescent; wing membranes hyaline, veins dark reddish-brown; tegula and tibial spurs piceous.
STRUCTURE. — Antennal scape almost as long as first four flagellar segments together; flagellar segments as in caerulea. Eyes, mandible and galea as in caerulea. Maxillary palpus as in caerulea but segmental ratio about as 1.0; 1.0.0.9:0.9:0.6:0.6. Labial palpus as in caerulea but ratio about as 1.0:0.7:0.4:0.5. Labrum as in caerulea, process not emarginate apically. Clypeus moderate in length, slightly flattened apicomedially, with deep round punctures separated mostly by one-half to one puncture width or less; surface shiny, unshagreened except at extreme base. Supraclypeal area with minute crowded punctures. Face above antennal fossae with longitudinal rugulae and distinct interrugal punctures, moderately shiny; below antennal fossae shiny and punctate. Vertex above lateral ocellus slightly shorter than one ocellar diameter (about as 6 of 7:8), sculptured as in caerulea. Facial fovea narrow, short, as in caerulea, separated from lateral ocellus by more than one ocellar diameter (about as 11:8). Genal area as in caerulea.
Thoracic form and sculpturing as in caerulea except as follows: generally shinier; mesoscutum with fine shagreening only anteriorly, punctures distinct, deep, separated mostly by half to one puncture width or less, small; scutellum similar; propodeum sculptured as in dissimulans. Wing venation and vannal lobe hind wing as in caerulea. Tarsal claws and tibial spurs normal.
terga with surfaces reticularly shagreened but moderately shiny. Tergum I with disc. with small round punctures separated mostly by two puncture widths. Terga 2-4 with disc with punctures distinct, separated by one to two puncture widths or less, apical areas minutely punctate, shagreened. Sterna 2-5 with small piliferous punctures much as in caerulea. Pygidial plate as in caerulea.
VESTITURE. — Head white except as follows: dark brown on mandibles, on face below vertex, alongside compound eye to clypeus, mixed with white on clypeus and on genal area near eye margin. Thorax white except brown on venter; leg hairs dark brown (including scopal hairs) except hind femur paler brown and inner surfaces tarsi golden. Terga 1-4 with sparse pale hairs, without distinct apical fasciae, terga 5 and 6 mostly brown; sternal hairs dark brown. Pollen-collecting hairs as in dissimulans.
MALE. MEASUREMENTS AND RATIOS. — N = 7; length, 7-8 mm; width, 1.5-2.0 mm; wing length, M = 2.60 ± 0.157 mm; FL/FW, M = 1.01 ± 0.008; FSI/FS2, M (6) = 1.56 ± 0.048.
INTEGUMENTAL COLOR. — Metallic blue but clypeus with violaceous reflections; otherwise as in female but terga with apical areas translucent, smoky and only narrowly rufescent basally; tibial spurs testaceous.
STRUCTURE. — Antenna as in caerulea but scape length equal to first two and one-half flagellar segments or slightly more and flagellar segment 1 only slightly longer than 3. Eyes as in female but shorter, about as long as three times width. Mandible and galea as in female. Maxillary palpus as in female but segmental ratio about as 1.0:1.0:0.8:0.8:0.7:0.7. Labial palpus as in female. Labrum as in female but process feebly emarginate apically. Clypeus as in dissimulans but usually with distinct punctures. Supraclypeal area, face above antennal fossae, vertex and genal area as in female but often slightly duller.
Thoracic form and sculpturing as in caerulea but propodeum outside of dorsal enclosure more densely punctate and enclosure more roughened. Wing venation and vannal lobe hind wing as in dissimulans. Tibial spurs and tarsal claws normal.
Terga and sterna sculptured as in dissimulans. Terminalia as in figures 60-64; note the following: genital capsule much as in suavis or caerulea; sternum 7 longer than usually with small apical emargination; sternum 8 with apex large and rounded.
VESTITURE. — White except as follows: head brown on face below vertex and down to lateral corners of clypeus, mixed with white on clypeus, on genal area in narrow zone alongside compound eye. Terga 2-4 with distinct apical fasciae broadly interrupted medially composed of relatively short, decumbent hairs; tergum 5 with weak, complete fascia of sparse hairs. Sterna 2-5 with weak subapical fimbriae of short white hairs but not complete laterally, shorter than in Thysandrena and not as thick (more distinct than in most Euandrena species).
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