Identification Summary: This is one of only 2 eastern species that have only 2 submarginal cells (The other is the undescribed species MR_1 and is very tiny). Further to the west a closely related but molecularly distinct sister species has 3 cells. In this species the 2 cell situation is clearly caused by the simple loss of the first transcubital vein.|
Reprinted with permission from: Mitchell, T.B. 1962 Bees of the Eastern United States. North Carolina Agricultural Experiment Station Technical Bulletin No. 152.
FEMALE—Length 7-8.5 mm.; lateral ocelli slightly nearer margin of vertex than to each other; cheeks only slightly narrower than eyes, posterior margin carinate; longer side of basal segment of flagellum equal to segment 2, median segments slightly longer than broad; mandibles slender and simple apically; wings subhyaline basally, becoming somewhat yellowish apically, with only two submarginal cells due to the loss of the first transverse cubitus (fig. 106), the first recurrent vein thus entering the first submarginal cell, the 2nd entering the 2nd submarginal near the middle, veins testaceous, basal vein slightly basad of transverse median; tegulae shining between quite deep and distinct punctures, these quite sparse posteriorly and along outer margin; posterior margin of scutellum slightly impressed medially; front coxae not spined; apex of hind tibiae with 3 or 4 short but distinct, testaceous bristles; face largely yellow below level of antennae, with a small amount of black between ocelli, upper part of face, vertex and cheeks largely ferruginous, a small area of yellow posterior to eyes below, the lateral face marks ending narrowly near top of eye; antennal scape reddish-yellow anteriorly, flagellum more brownish-testaceous; thorax largely red, but pronotal collar, tubercles, two large spots on scutellum and some more or less vague spots on propodeum posteriorly, yellow; tegulae more testaceous; metapleura and narrow adjacent margin of propodeum black; posterior surface narrowly black medially; abdomen red, terga 2-5 with broad, transverse, yellow bands, those on 2 and 3 strongly constricted medially, sometimes more or less broadly interrupted, those on 4 and 5 of rather uniform width, sub- median on all except on 5 where it is more nearly apical; legs in large part reddish-testaceous, spurs pale yellow; face above antennae, vertex and cheeks rather coarsely rugoso-punctate, punctures close but distinct on lower part of face, very fine and close on supraclypeal area, shallow but distinct and rather coarse on clypeus; scutum with coarse, deep and contiguous punctures, those on the shining scutellum quite sparse, mesopleura quite coarsely rugoso-punctate, propodeum more finely rugose, especially at sides, triangle somewhat rugose medially, becoming irregularly and finely striate at each side above; discs of abdominal terga very finely, closely and rather distinctly punctate, rather sparsely so toward apical margins; tergum 1 impunctate laterally and basally; pseudopygidium transverse, rather extensive, median length nearly half the breadth, forming the truncate apical margin of tergum 5, densely covered with suberect, silvery tomentum; pubescence extremely short in general, thin, more elongate and copious on head below, entirely whitish where evident, very obscure on abdomen dorsally, sternum 5 apically with a pair of tufts of elongate hairs on each side which converge medially.
MALE—Length 7-9 mm.; lateral ocelli considerably nearer margin of vertex than to each other; cheeks subequal to eyes in width, posterior margin subcarinate; antennal scape strongly swollen, apex deeply excavated and completely enclosing pedicel, longer side of basal segment of flagellum somewhat shorter than segment 2, median segments slightly broader than long; mandibles slender and simple apically; wings hyaline basally, becoming somewhat yellowish apically, with but two submarginal cells due to the loss of the first transverse cubitus, 1st recurrent vein thus entering 1st submarginal, 2nd entering at middle of 2nd submarginal, veins testaceous to piceous, basal vein somewhat basad of transverse median; tegulae shining between rather deep, distinct, fine and rather close punctures; posterior margin of scutellum rather deeply grooved; front coxae not spined; hind femora slender and simple; face entirely yellow below level of antennae, lateral face marks extending very narrowly to top of eye, and cheeks below yellow along posterior eye margin nearly to the top; face above antennae, vertex and cheeks posteriorly, black; antennal scape yellow anteriorly, piceous posteriorly, flagellum brownish-testaceous; pronotal collar, tubercles, tegulae, scutellum in large part, a pair of rather conspicuous, lateral maculations on propodeum posteriorly, and a large anterior maculation on mesopleura, bright yellow, thorax otherwise black; front legs, including coxae, largely yellow, the femora and trochanters more ferruginous posteriorly; mid and hind legs more ferruginous, femora yellow apically, mid tibiae more or less yellow anteriorly, mid basitarsi yellow, spurs pale yellow; abdominal terga 2-6 with broad, transverse, yellow bands, these somewhat constricted medially on 2 and 3, of more uniform width on 4-6, basal tergum piceous basally, more or less testaceous medially, and darker red apically; sterna 2-6 more or less yellow, apical margins testaceous-hyaline; face above antennae, vertex and cheeks quite coarsely rugoso-punctate, punctures rather shallow but close and coarse on face below antennae, crowded on supraclypeal area, and quite distinct on clypeus, becoming very sparse on each side; scutum and mesopleura densely and rather coarsely rugosopunctate, punctures of scutellum more distinct, coarse, deep and rather close, more shallowly rugose on propodeum, both posteriorly and laterally, the triangle rather coarsely and sparsely striate; discs of abdominal terga with close, fine, quite deep and distinct punctures, these becoming somewhat more coarse and sparse apically on the more apical terga, but quite close across disc of tergum 6; pubescence rather short, entirely pale, quite copious over most of head and thorax, very short and inconspicuous on abdomen dorsally, very thin and sparse on sterna 1-5, sternum 6 with quite dense, erect, pale hairs apically; median length of pygidial plate about equal to basal width, quite strongly narrowed to the sub- truncate tip which is sometimes incised medially, margins carinate, surface very closely punctate; exposed sternal plates unmodified, sternum 6 subtriangular, apex rather narrowly rounded; sternum 8 with a slender apical process; gonocoxites of genital armature as shown (fig. 105).
DISTRIBUTION — Minnesota to New York, south to South Carolina, April to June.
FLOWER RECORDS — Stellaria and Taraxacum. Robertson (1929) records this species on Antennaria, Chaerophyllum, Claytonia, Heracleum, Prunus, Salix and Viburnum.