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Extracted from: Timberlake P.H., (1969). A Contribution to the Systematics of North America Species of Synhalonia (Hymenoptera, Apoidea). University of California Publications in Entomology Volume 57
The female of virgata may be recognized by its dull sculpture and by having four white bands on the abdomen, with that on tergite 5 usually complete, but diminished in width across the middle by having its posterior half brown. The male falls in the key near belfragei, but differs in having the vertex well impressed on each side and the hair of the abdomen black beyond the basal tergite. Only 2 males and 26 females have been seen.
Female.—Black; tibial spurs pale testaceous; small joint of tarsi dark but claws ferruginous on basal half. Tegulae dark amber on apical half and fuscous at base. Wings strongly dusky, nervures dark ferruginous or piceous, subcosta black. Pubescence moderately long, erect, not dense enough to conceal sculpture, ochreous or brownish on notum of thorax and paler or whitish beneath and on head. Hair of tergite 1 rather short, erect, and white. Broad bands on four following segments white or slightly ochreous. Hair of tergite 2 entirely light, but dense and appressed on apical depression and moderately receding from apical margin across middle. Base of tergites 3 to 5 with dense black hair, with light band on tergite 3 intruding more or less onto disk beyond apical depression. Long hairs overhanging apical bands on tergites 3 and 4 entirely pallid and difficult to see (these black and conspicuous in lunata). Apical band on tergite 5 white, but narrowed across middle by becoming brown on posterior half, or more rarely entirely brown across middle. Hair of tergite 6 black. Sternite 6 with short, dense, and fine brown hair; long fringes on preceding sternites whitish but fulvous across middle of sternite 5 and slightly tinged with fulvous on sternite 4. Hair of legs whitish, dark ferruginous on inner side of middle and hind basitarsi, and chocolate brown on inner side of front basitarsi; scopal hair of hind legs white or tinged with ochreous.
Head much broader than long; inner orbits of eyes parallel. Vertex very slightly impressed on each side; lateral ocelli their distance apart from nearest eye and slightly more than their diameter from occipital margin. Proboscis moderately long; galeae minutely tessellate and shin¬ing, nearly hairless. Second submarginal cell receiving recurrent nervure one-fifth or less of its length from apex. Clypeus finely and densely rugoso-punctate. Frons and vertex dull, with small dense punctures. Mesonotum opaque, punctures of scutum dense but obscure, and those of scutel-lum fine and dense. Abdomen minutely and densely punctured, the sculpture evident on tergite 1 and across middle of tergite 2, but otherwise concealed by dense pubescence; apical depression of tergite 1 bare and impunctate on apical half, and tergite 2 narrowly bare and impunctate across middle of apical margin. Pygidial plate about as long as wide at base, and rather broadly rounded at apex, its disk plane. Length 11.5-13.5 mm, anterior wing 9-9.5 mm, width of abdomen 4.7-5.2 mm.
Male.—Black; small joints of tarsi, tibial spurs, tegulae, and wings as in female. Labrum and clypeus yellow; clypeal mark moderately well separated from margin of eyes, obtusely notched on each side, with lateral margins of clypeus narrowly black. Pubescence of thorax pale ochreous, paler or whitish beneath and on head, moderately long and dense. Hair of tergite 1 long, erect, whitish, that of following segments entirely black, or whitish and brown across apex of tergite 6 and brown on tergite 7. Hair of venter black, with fringes on sternites 1 and 2, and on each side of sternite 4, and sometimes 5, white. Hair of legs white, ferruginous on inner side of basitarsi.
Head much broader than long; inner orbits of eyes only slightly divergent above. Vertex well impressed on each side, with summit of eyes prominent; lateral ocelli their distance apart from nearest eye and their diameter from occipital margin. Antennae slender, reaching base of tergite 3, and moderately compressed; joint 3 on its short side about as long as wide and one-fourth as long as joint 4. Oculoclypeal space narrow. Second submarginal cell receiving recurrent ner-vure one-fifth, or less, of its length from apex. Legs normal, middle basitarsi slightly longer than tibiae. Clypeus moderately shining, with close, very shallow punctures. Frons and vertex dull, finely and densely punctured. Mesonotum opaque, densely and very obscurely punctured. Abdomen shining, minutely and densely punctured; apical margin of tergites very narrowly impunctate. Sternite 6 with strong, oblique impression on each side, but not causing marginal lobes; inner margin of impression with a ridge, continued along lateral margins but not elbowed; disk with shallow median impression extending triangularly to middle, and with short, very fine and dense pubescence along apical margin, and very short, erect pubescence at base. Sternites 7 and 8 as figured. Parameral lobes of genital armature rather short and slender, gently arcuate, widened at base, thinly contracted at middle and evenly expanded and truncate at apex. Length 13 mm, anterior wing 9.8 mm.
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