Extracted with permission from: Onuferko, T.M. 2017. Cleptoparasitic Bees of the Genus Epeolus Latreille (Hymenoptera: Apidae) in Canada. Canadian Journal of Arthropod Identification No. 30: March 30, 2017. doi:10.3752/cjai.2017.30
Diagnosis. Among Canadian species, E. pusillus most closely
resembles E. scutellaris. Both species exhibit the following
similarities: axilla large and robust, its tip attaining or
surpassing line of pale tomentum marking posterior margin of
mesoscutellum, and its lateral margin arcuate; Ti with discal
patch very wide; and metasomal fasciae rather thin.
Differences are as follows: in E. pusillus, mesopleuron of male
entirely obscured by white tomentum; at least mesoscutellum
entirely black (entirely black to entirely ferruginous in E.
scutellaris); and T5 with pseudopygidial area of female
narrower (apex <2 x medial length) than in E. scutellaris (apex
2 x medial length). In addition to the diagnostic differences
included in the key are the following: in contrast to E.
scutellaris, paramedian band of E. pusillus may be quite long,
attaining or surpassing 3/5 length of entire mesoscutum; and in
E. pusillus, fascia of T2 always with lobe-like anterolateral
extensions of tomentum, whereas in E. scutellaris such
extensions may be entirely absent.
Distribution in Canada: Central Canada (Map 12).
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 9 mm.; black, antennal scape brownish-testaceous anteriorly, mandibles testaceous, becoming reddened at tips; tegulae and legs testaceous, mid and hind spurs piceous, tubercles and axillae more or less infused with ferruginous; lateral ocelli separated from margin of vertex by a space somewhat less than their diameter; cheeks very narrow, subcarinate posteriorly, becoming still narrower below; labrum nearly twice as broad as median length, with a pair of distinct, subapical tubercles; inner margin of mandibles with a quite distinct submedian angle; hind margin of scutellum very slightly outcurved, much exceeded by the robust, sub- triangular axillae which are very broadly joined to lateral margins of scutellum and sub-carinate laterally (fig. 110); wings with the usual three submarginal cells, subhyaline basally, becoming faintly infuscated apically, veins brownish; face quite densely pale tomentose around bases of antennae, over clypeus and cheeks, more thinly so above where it is more yellowish; margin of pronotum and tubercles, a pair of anterior longitudinal lines and extreme lateral margins of scutum, metanotum, and adjacent margin of scutellum, quite densely, pale yellow tomentose; lateral portions of posterior face of propodeum rather thinly pale tomentose, becoming more densely so beneath wing bases above; abdominal terga 1-4 with entire, transverse, yellow tomentose fasciae, these only sub-interrupted medially, somewhat separated from apical margin of discs except on 4, anterior face of tergum 1 densely yellow tomentose, median area black, basal and apical tomentose areas narrowly connected at each extreme side; tergum 5 with a subapical area of pale tomentum which encloses the small pseudopygidium; punctures deep, close and rather coarse on upper part of face, becoming very minute and densely crowded on clypeus and lower part of face, and on cheeks; pleura closely punctate below but with some definite, irregular, shining interspaces evident, very densely crowded above; scutum closely and quite coarsely punctate throughout, punctures more distinct anteriorly, densely crowded posteriorly and over entire scutellum and axillae; tegulae with very fine and close punctures throughout; abdominal terga with minute and very close, uniformly distributed punctures, these obscured by black, plumose tomentum; pseudopygidium very narrow, median length about equal to apical width.
MALE—Answers in general to description of female, but face around and below antennae very densely silvery tomentose, and entire ventral and lateral surfaces of mesothorax, as well as hind coxae, very densely silvery tomentose; pygidium subtriangular, rather narrowly rounded apically, margin carinate, basal width about equal to median length, surface rather sparsely and minutely punctate, with a few very short, suberect hairs.
DISTRIBUTION—Wyoming and Texas to Maine and Florida; April and May in Florida, August to October in the North.
FLOWER RECORDS—Aster, Erigeron, Eupatorium, Haplopappus, Helenium, Melilotus and Solidago. This is recorded by Robertson (1929) on Bidens, Boltonia, Coreopsis, Helianthus and Polygoneum.