Reprinted with permission of the American Entomological Society from:
LaBerge, W. E. 1971b. A revision of the bees of the genus Andrena of the Western Hemisphere. Part IV. Scrapteropsis, Xiphandrena, and Rhaphandrena. Transactions of the American Entomological Society 97: 441-520.
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This species was described from a few females from North Carolina and Georgia. Additional specimens make known the male and extend the range as far west as Texas and eastern Nebraska. A. rubi is most closely related to A. unicostata but also bears some resemblance to alleghaniensis. The female of rubi have the short, scale-like hairs on the thoracic dorsum as in alleghaniensis, although the hairs are more erect and paler in color. The female of rubi differs from those of other members of this group of species by the ventral ridges of the hind femur being variable, the scutellar and metascutal punctures being more crowded, the tergal punctures being more crowded, and the second (and third) tergum having a shorter apical area. The male differs from other males of this group by the same sculptural characters marking the females, the short apical area of the second sternum and the much shorter first flagellar segment in relation to the second segment.
FEMALE. MEASUREMENTS AND RATIOS. — N = 20; length, 8-10 mm; width. 3.0-3.5 mm; wing length, M = 3.46 ± 0.1 II mm; FL/FW, M = 1.01 ± 0.004; FOVL/FOVW, M = 3.06 = 0.049.
INTEGUMENTAL COLOR. — Generally as in alleghaniensis but wing membranes only moderately infumate, veins reddish-brown, and terga 2-4 with apical margin narrowly rufescent.
STRUCTURE. — Structure and sculpturing of head as in alleghaniensis except as follows: galea dulled by fine reticular shagreening; clypeus usually without impunctate median line; facial fovea short, extending below to level of lower margins of antennal fossae or slightly more, broad.
Structure and sculpturing of thorax as in alleghaniensis except as follows: scutellar punctures crowded even anteriorly; mesoscutal punctures in posteromedial area separated mostly by one puncture width: propodeum with dorsal enclosure with one median longitudinal ruga and several weaker rugae on either side. rugae often irregular and anastomizing, dorsolateral and posterior surfaces always finely punctatorugose and tessellate, lateral surface with few or no rugulae posteriorly. Wing venation as in imitatrix but vein 1st m-cu meets second submarginal cell at or before middle of cell, rarely (one specimen) slightly beyond middle. Legs as in alleghaniensis except hind femur with ventral ridges variable-one-third of specimens without ridges (but surfaces irregular), one-third with one complete ridge and one-third with two ridges often meeting near middle of femur.
Metasomal tergum 1 with basal area with deep round punctures separated mostly by half to one puncture width; apical area with slightly smaller punctures separated by half a puncture widths or less. surface shiny. Tergum 2 similar but basal area punctures more crowded. Terga 3 and 4 as in tergum 2 but basal area punctures progressively slightly sparser. Pygidial plate as in alleghaniensis. Sterna us in alleghaniensis but apical areas shorter, sternum 2 with apical area no longer medially than one-third of sternum or shorter.
VESTITURE. — Generally as in alleghaniensis except as follows: thoracic dorsum with hairs short and scale-like but erect, pale to bright ochraceous; terga 2-4 with distinct apical fasciae of dense white pubescence interrupted medially on tergum 2 and occasionally narrowly interrupted on tergum 3.
MALE. MEASUREMENTS AND RATIOS. — N = 10; length, 8-9 mm; width. 2.0-2.5 mm; wing length, M = 3.22 ± 0.179 mm; FL/FW, M = 1.06 ± 0.005; FS1/FS2, M = 0.68 ± 0.021.
INTEGUMENTAL COLOR. — Generally as in alleghaniensis except as follows: wing membranes colorless or slightly infumate. veins and pterostigma red 10 reddish-brown; hind tibial spurs testaceous.
STRUCTURE. — Head with structure and sculpturing as in alleghaniensis except as follows: first flagellar segment usually much shorter than second segment which is only slightly shorter than third; galea dulled by fine reticular shagreening.
Thoracic sculpturing and structure as in alleghaniensis but propodeum with dorsal enclosure as described for female and dorsolateral and posterior surfaces only finely punctatorugose. Wing venation as in female. Legs as in alleghaniensis.
Metasomal tergum 1 with basal area punctures separated mostly by one to two puncture widths, apical area with punctures smaller and separated by less than one and mostly less than one-half a puncture width, surface shiny. Tergum 2 similar to tergum 1 but punctures usually slightly more crowded in basal area. Terga 3-5 as in tergum 2 but punctures progressively sparser. Sterna as in alleghaniensis but sterna 2 and 3 with apical areas shorter than one-third of median tergal length and basally terga 2-5 with punctures separated mostly by two puncture widths, surfaces dulled by coarse reticular shagreening. Sternum 6 reflexed as in alleghaniensis.
Terminalia as in figures 37-38: note the following: sternum 7 much as in alleghaniensis but apical hairs shorter and sparser; sternum 8 as in alleghaniensis but apical narrow area slightly bulbous basad and with sparse hairs in this area; genital capsule as in alleghaniensis.
VESTITURE. — Generally white and distributed as in alleghaniensis except terga 3-5 with distinct apical fasciae of white pubescence, usually present laterally on tergum 2 as well.
Reprinted with permission from: Mitchell, T.B. 1960. Bees of the Eastern United States. North Carolina Agricultural Experiment Station Technical Bulletin No. 141.
FEMALE. — Length 9 mm.; clypeus slightly convex, projecting about one-third below suborbital line, shining between deep, distinct, rather fine and close punctures, these slightly separated toward middle where an obscure impunctate line is partially developed; facial foveae rather narrow, occupying above little more than half of space between eyes and ocelli, only slightly narrowed below, covered with whitish tomentum; space between margin of vertex and lateral ocelli subequal to their diameter; cheeks very slightly broader than eyes, rounded posteriorly, very finely and closely punctate, surface dull, punctures only very slightly separated above on vertex laterally where surface is more shining; malar space very short; basal segment of flagellum slightly shorter than 2nd and 3rd combined; process of labrum broad basally, abruptly narrowed to a very small, slightly produced tip, which is slightly incised medially; pubescence of head, thorax and legs whitish, becoming somewhat yellowish above on head, that on dorsum of thorax more yellowish, short and rather densely plumose, almost scale-like; punctures of scutum moderately coarse, quite close and shallow anteriorly, becoming somewhat more distinctly separated, but still close, near center posteriorly, surface quite dull, those on scutellum more coarse and irregular, intervening spaces more evident, shining; pleura rather finely rugose, becoming smoother and more distinctly punctate posteriorly, where surface is quite densely tessellate; dorsal area of propodeum oblique, triangle with a few irregular striae medially, these becoming obsolescent laterally; propodeal corbicula whitish, short and poorly developed, without an anterior fringe; trochanteral floccus whitish, rather long and well developed; hind tibiae quite slender, only slightly broadened apically, apex not nearly twice width of basitarsi, scopa rather dense, hairs of moderate length, entirely simple, white, becoming somewhat fuscous toward base posteriorly; fore and mid basitarsi somewhat narrower than their respective tibiae; 2nd submarginal cell slightly shorter than 3rd, receiving 1st recurrent near middle; abdominal terga smooth and shining between deep, distinct, quite uniformly close punctures, these rather coarse, apical impressed areas shallow and obscure, quite narrow, occupying hardly one-third length of disc medially, discal pubescence very short, thin, erect, apparently entirely pale, terga 2-4 with dense, white, apical fasciae, somewhat interrupted medially on tergum 2, tergum 5 with a whitish, apical fimbria.
TYPES. — Holotype: Female, Carolina Beach, N. C., April 20, 1930 (Mitchell, on Rubus). Paratypes: 4 FF, topotypical; 2 FF, Beaufort, N. C., April 20, 1947 (Mitchell, on Aronia); 1 F, Taylorsville, Ga., April 30, 1939, (P. W. Fattig) [all author's coll.]
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