Reprinted with permission from: Mitchell, T.B. 1962 Bees of the Eastern United States. North Carolina Agricultural Experiment Station Technical Bulletin No. 152.|
Megachile inimica inimica
FEMALE—Length 13-16mm.; abdomen elongate and parallel-sided; black, tegulae yellowish-hyaline, legs ferruginous, spurs yellow; eyes parallel; apical margin of clypeus slightly rounded medially with a more obtuse angle on each side; mandibles 4-dentate, a quite conspicuous bevelled edge between 2nd and 3rd teeth; lateral ocelli considerably nearer eyes than to margin of vertex; cheeks very slightly broader than eyes below, somewhat narrower above; vertex somewhat shining, punctures quite deep and distinct, slightly separated, of two rather distinct sizes, cheeks quite closely punctate somewhat more coarsely so below, becoming very fine and quite close along margin of eyes, especially above; face below ocelli quite densely rugoso-punctate, becoming more distinctly but closely punctate laterally, supraclypeal area considerably swollen, punctures quite coarse and densely crowded, those on clypeus very close but distinct and quite coarse; pubescence white but rather short on face laterally, between antennae and on cheeks, becoming somewhat more elongate on cheeks below where there are intermixed, yellow hairs; clypeus with erect, rather conspicuous, yellowish pubescence; vertex rather sparsely beset with erect, more fusous hairs; thorax rather thinly white pubescent laterally and posteriorly, with snow-white tufts of tomentum around tubercles; scutum with very short and obscure, erect, dark hairs, those on scutellum rather sparse and elongate; scutum densely and rather finely punctate in large part, punctures slightly separated only in center; scutellum quite flat, punctures close but irregular, rather fine and densely crowded on axillae; pleura dull, punctures rather coarse but densely crowded throughout, lateral faces of propodeum somewhat smoother but rather dull, posterior face more velvety, punctures very vague and obscure, hardly evident; front and mid basitarsi distinctly narrower and shorter than their tibiae, hind basitarsi nearly as broad and fully as long as their tibiae; tegulae shining, punctures hardly evident; wings rather deeply infuscated, veins brownishpiceous; abdominal terga 2-4 with very deep and entire, sub-basal grooves, basal margins of grooves distinct but not carinate, apical margins of terga 2-5 quite abruptly and deeply depressed, rather thinly white fasciate, the fasciae more dense and conspicuous laterally; tergum 1 with rather thin and elongate pale pubescence, discal pubescence of 2-4 very short and inconspicuous but quite copious, largely dark, that on 5 and 6 more elongate and conspicuous; punctures of terga fine but deep and distinct, close on the more basal terga, becoming somewhat more widely separated on 4and 5 apically; apical rounded apex of tergum 6 rather sharply upturned, surface very densely and rather finely rugoso-punctate, with no pale tomentum evident; sternum 6 rather uniformly covered with very short, blackish, scopal hairs, the tip very slightly incurved or emarginate, without a definite apical fringe; scopa otherwise yellowish-white, the more basal sterna with very fine and close punctures, these becoming more coarse and distinct on the more apical sterna, apical margins rather deeply depressed and yellowish-hyaline; no sternal fasciae evident.
MALE—Length 11-14 mm.; black, tegulae yellowish-testaceous, legs ferruginous, but front tarsi and spurs yellowish; eyes subparallel; clypeal margin beneath beard nearly straight, but with a very shallow, median, in- curved area; mandibles 3-dentate (fig. 56), inferior process sub-basal, rather short, subacute, lower margin and tip very densely short, pale pubescent; apical segment of flagellum slender and elongate; lateral ocelli considerably nearer eyes than to margin of vertex; cheeks subequal to eyes in width, narrowed and very densely pubescent below, with a conspicuous, flattened protuberance just beneath base of mandible, which is densely pubescent on its lower surface; vertex somewhat shining, punctures deep and distinct, but rather fine and uniformly close, fine and close on cheeks above, becoming obscure or sub-rugose below, a narrow, transverse, impunctate line near lower margin, clothed on upper side by a narrow fringe of white hairs, with very dense and abundant, long white pubescence below; entire face and clypeus below ocelli very finely and densely rugose beneath dense pubescence; face with copious, yellowish-white, more or less erect pubescence, that on cheeks white, rather thin above, dense and elongate below, short and more or less fuscous across vertex; thorax with rather short and dense, white pubescence laterally and posteriorly, scutum with rather short, erect, fuscous pubescence, becoming whitish anteriorly, scutellum with a few dark hairs interspersed in the generally elongate, erect, whitish pubescence; dorsum of thorax rather dull, punctures finely and densely crowded throughout; pleura dull beneath the pubescence, punctures densely crowded throughout, lateral faces of propodeum somewhat smoother, with numerous, shallow and rather obscure punctures, posterior face becoming somewhat more velvety, punctures more shallow and obscure; front coxal spines slender and elongate, surface of coxae quite flat, with a small patch of robust, ferruginous bristles anterior to each spine; front tarsi yellow, basitarsus dilated and deeply exacavated anteriorly, somewhat broader than their tibiae, the resulting anterior scale producedover segment 2 but not attaining its tip, anterior and posterior margins of the segment somewhat brownish, posterior creamy-white fringe rather short but dense, more or less yellowish beneath; combined length of segments 2 and 3 about equal to basitarsus, each with a rather obscure, posterior, integumental dark spot; mid and hind basitarsi slender and elongate, much shorter than their tibiae; mid tibal spurs well developed; tegulae shining, punctures exceedingly minute but rather close; wings subhyaline basally, becoming faintly infuscated apically, veins brownish testaceous; abdominal terga 2-5 quite deeply grooved or depressed across base, basal margin of these grooves quite sharply carinate, apical margins of terga rather narrowly but abruptly depressed, with entire, dense, pale, apical fasciae; pubescence of basal tergum rather copious and elongate, entirely whitish, discal pubescence of following terga very short but quite dense, fuscous to black, some pale pubescence across base of 2, and 5 with sub- erect, and more elongate, fuscous hairs; punctures of terga very fine but quite deep and distinct, uniformly close on 2-4, becoming somewhat more irregular and obscure on 5; tergum 6 nearly vertical, very finely and densely rugoso-punctate, carina rather low but abrupt, broadly rounded and very shallowly emarginate medially, no pale tomentum evident, but with scattered, erect, fuscous hairs, median teeth of apical margin evident only as very low, transverse carinae which are much nearer each other than to the obscure lateral angles; tergum 7 barely evident, slightly acute medially; sterna 1-4 exposed, quite deeply and distinctly punctate, punctures rather coarse toward base of each plate, becoming more sparse apically, apical margins rather deeply depressed, yellowish-hyaline, not conspicously fringed; setose area of sternum 5 covering most of apical half of plate, the setae sparse and simple, more robust toward base; setose areas of sternum 6 rather widely separated, obscurely bilobate, basal lobes elongate and acute laterally, with simple, long and robust setae, the apical lobes produced laterally, fringed with 2 or 3 rows of robust, flexed and dilated setae, apical marginal lobe of plate broad, truncate apically; (fig. 61) gonocoxites constricted above base, slightly dilated and obliquely compressed apically (fig. 58).
DISTRIBUTION—Florida to Texas, and south to Guatemala, February to April.
FLOWER RECORDS — Achyranthes, Avicennia, Borrichia, Coccolo ba, Laciniaria, Ocimum, Salvia, Vitex and Ximensia. Graenicher records this species on Bidens and Crotalaria.
Megachile inimica sayi
This is the more northern form of this
species which differs from the typical form chiefly in the black legs in both sexes. The pubescence, including the fasciae, is usually white in sayi, while in typical inimica there
a considerable tendency to yellowish color of pubescence. No differences of structure or sculpture that seem to be of any consequence have been found.
DISTRIBUTION—Pennsylvania to Florida, west to California and Mexico, July to September, and in Florida, to November.
FLOWER RECORDS—Chrysopsis, Cleome, Coreopsis, Gilia, Helenium, Helianthus, Heliopsis, Melilotus, Stropho styles, Verbena and Vernonia. Robertson (1929) records this subspecies on the following:
Arctiu’in, Aster, Biclens, Blephilia, Brauneria, Cephalanthus, Lepachys, Liatris, Lythrum, Petalostemum, Pycnanthemum, Budbeckia, Silphium and Teucrium.