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 9.5-12 mm.; entirely black, including tegulae and legs; eyes slightly convergent below, lateral ocelli much nearer each other than to eyes, and separated from margin of vertex by little more than their own diameter; cheeks subequal to eyes in width, carinate posteriorly, angulate but not excavated below; clypeus quite flat, broadly, triangularly produced apically, apex in some specimens slightly upturned; mandibles somewhat swollen medially on outer margin, middle tooth distinct but rather small; punctures coarse, deep and distinct in general, well separated but not sparse across vertex and between ocelli, becoming close and coarse on cheeks above, fine, shallow and obscure below; face below ocelli more finely rugoso-punctate, becoming very finely rugose on supraclypeal area, on sides of face and over clypeus, a short, median, longitudinal ridge between antennae; pubescence of head and thorax entirely pale, rather copious and elongate around antennae and ocelli and on cheeks below, short and rather thin on cheeks above, very short and subappressed on supraclypeal area and clypeus, becoming strongly yellowish on elypeus apically, yellowish on mandibles with numerous, elongate, erect hairs; pleura with rather elongate but thin, white and rather copious pubescence, posterior face of propodeum quite copiously long pubescent; transverse carina of tubercle very low and inconspicuous, largely obscured by erect pubescence; apical margin of scutellum somewhat outcurved, rounded, without a distinct, posterior and dorsal face; axillae very short and rather blunt, projecting but very slightly from margin of scutellum; coxal spines reduced to broadly carinate, triangular tubercles; wings subhyaline basally, lightly infuscated apically and along margin, recurrent veins reaching 2nd submarginal cell subequally distant from base and apex; punctures coarse, close and deep, rather uniformly distributed over most of scutum, scutellum, axillae and pleura, but somewhat finer on axillae and on scutellum laterally, slightly separated in center of scutum posteriorly; lateral faces of propodeum smooth but dull, posterior face dull and tessellate, with rather close but fine and obscure, vague punctures, dorsal area more velvety, becoming very faintly reticulate along dorsal margin; basal abdominal tergum shining, punctures deep and distinct but rather sparse medially, becoming somewhat finer and closer laterally, apical margin slightly depressed and densely white fasciate; terga 2 and 3 with shallow, transverse grooves which are narrowly obliterated medially, sub-basal at extreme sides but becoming median toward the center, portion of each with deep, distinct, rather fine, well separated punctures, these becoming quite close at extreme sides, the apical half somewhat more coarsely and sparsely punctate in center, becoming close laterally, and fine and close toward the depressed, apical rims which are densely white fasciate; tergum 4 somewhat depressed toward base at sides, but not definitely grooved, punctures about as those on 3, apical margin definitely white fasciate; tergum 5 rather finely and closely punctate across base, punctures becoming somewhat more widely separated toward apical margin, this with a very thin, apical fringe of whitish hairs; tergum 6 elongate-triangular, sides straight, with a median, longitudinal, faint line toward base, which continues as a quite distinct, median ridge toward apex, rather deepiy depressed on each side of this, apex narrowly rounded (fig. 65); sternum 6 narrow and elongate, strongly downcurved and protruding much beyond apex of tergum, conspicuously notched on each side toward tip, this part somewhat longer than the width at the notches; sterna 1-4 shining, deeply and rather coarsely and closely punctate, punctures somewhat more widely separated medially, apical margins narrowly depressed, subhyaline, with narrow fringes of white pubescence; sternum 5 produced apically, subtriangular, with rather numerous but well separated, coarser punctures toward base, these becoming very fine, indefinite and close toward apical margin, with a thin, whitish, apical fringe on each side of tip.
MALE—Length 7-11 mm.; entirely black, including tegulae and legs; eyes somewhat convergent below; lateral ocelli subequally distant from each other and margin of vertex, considerably more distant from eyes; cheeks subequal to eyes in width, subcarinate posteriorly, with a very broad and shallow, flattened area below which is not distinctly concave, but is margined with rather dense pubescence anteriorly and a fringe of long hairs posteriorly, ending at the quite distinct hypostomal carinae; clypeus very slightly convex, apical margin slightly produced, nearly straight, surface entirely covered with dense, pale pubescence; median length of labrum very slightly greater than basal width; median tooth of mandible well developed; punctures quite coarse, deep and distinct, slightly separated across vertex, upper cheeks becoming coarsely rugoso-punctate, face below ocelli densely and rather coarsely rugose, becoming very finely but densely rugose below antennae and over clypeus; pubescence entirely pale, quite copious and dense over most of face below ocelli, short and rather dense on cheeks below, thinner above; pubescence quite copious but rather short on pleura and posterior face of propodeum, without distinct, marginal fringes on the pleura; transverse carina of tubereles very low but evident; posterior margin of scutellum slightly outcurved, the posterior and dorsal faces not distinctly separated; axillae very short, protruding very slightly beyond limits of scutellum; coxal spines well developed but rather short, round at apex, densely pubescent posteriorly and laterally; wings subhyaline at base, becoming faintly clouded apically, recurrent veins reaching 2nd submarginal cell subequally distant from base and apex; punctures of pleura and dorsum of thorax quite uniformly coarse, close and deep; being contiguous in large part; lateral faces of propodeum rather smooth but dull, posterior face somewhat more shining, with close but very minute and obscure punctures, dorsal area more velvety, becoming rather broadly but very finely and obscurely rugose along upper margin; basal abdominal tergum shining, rather closely and deeply punctate, punctures slightly separated in median area, apical margin rather abruptly depressed, obscurely fasciate, with a dense, tomentose patch at each extreme side; terga 2 and 3 with transverse, uninterrupted, sub-basal grooves, basal area behind grooves rather evenly, finely and regularly punctate, punctures well separated; disc beyond the grooves more closely and coarsely punctate, but rather sparsely so in center, 2 with a quite deep and distinct but rather short fovea on each side, the margins of this narrowly impunctate, apical margins narrowly depressed, densely white fasciate toward sides but these rather widely interrupted or very narrow medially; terga 4 and 5 shining, closely and quite deeply punctate toward sides, the punctures more widely separated medially, with a basal, tomentose band and the depressed, apical rim white fasciate; tergum 6 white tomentose at base, very closely and finely punctate, rather deeply excavated in center, dorsal protuberances narrow and spine-like, elongate and strongly divergent, ventral spines less strongly divergent but equally long and slender, lateral spines much elongated and acute (fig. 66); sterna 1-4 shining, deeply and coarsely punctate, punctures rather well separated medially, becoming quite close laterally, apical margins rather broadly depressed and yellowish-hyaline, densely white fasciate; disc of sternum 4 not emarginate medially, but depressed rim with a very slight, median, triangular emargination; sternum 5 largely retracted, apical margin rather broadly incurved; sterna 6 and 8 entirely retracted, 8 rather narrowly subtruncate apically; gonocoxites of genital armature only slightly exceeding penis valves, somewhat compressed, with numerous, fine, erect, rather elongate hairs.
DISTRIBUTION — Alaska and British Columbia to Nova Scotia, south to Colorado, Indiana and Virginia; May to September.
HOSTS—Megachile centuncularis (L.) and M. relativa Cress.
Reprinted with permission from: Baker J. R. 1975. Taxonomy of five nearctic subgenera of Coelioxys (Hymenoptera: Megachilidae). The University of Kansas Science Bulletin 50(12):649-730.
FEMALE. Agrees with description and figures of Coelioxys rufitarsis except as follows: (1) Length 10-12 mm; (2) integument black, tegula, legs and apex of metasoma black to dark brown; (3) pubescence white, scattered golden erect setae on clypeus, golden setae on tarsi; (4) ocular hairs short (about 0.7 mm); (5) clypeus covered by short appressed setae and erect golden setae which are more numerous near apical margin, margin broadly outcurved, clypeal profile straight; (7) paraocular area almost obscured by setae about 0.2 mm long; (11) interocellar distance slightly greater than ocelloccipital distance and less than ocellocular distance; (14) hypostomal area with setae subequal in length to those on disc; (16) scutum with almost no squamose setae; (17) setae of mesepisternum usually not forming discrete fasciae; (19) axilla short (Fig. 23B); (20) metanotal setae erect, (22) terga 2, 3 with less conspicuous gradular grooves than shown in Figure 21, gradular groove of tergum 3 almost obliterated medially, postgradular areas more closely punctured than shown in Figure 21, fasciae of terga 4, 5 almost obliterated medially, tergum 6 not angled, elongate (Fig. 24C); (23) sternum 6 elongate, lanceolate apically (Fig. 24C).
MALE. Agrees with description and figures of Coelioxys rufitarsis except as follows: (24) Length 7-11 mm; (25) integument as in female (2 above); (26) pubescence white, golden on tarsi; (27) clypeal. margin irregular with 5 or 6 small denticles; (30) paraocular area with integument rugose, visible among long (035 mm), slender, erect setae; (31) rest of face contiguously, deeply punctured to ocellar area, visible among slender setae (about 0.5 mm long); (34) ocelloccipital distance subequal to or greater than interocellar distance, less than ocellocular distance; (35) vertex more closely punctured than shown in Figure 21; gena in lateral view subequal in width to eye, ventral angle greater than 900; (37) hypostomal area of gena with dorsal carina of excavation extending to the preoccipital carina, excavation with setae of anterior fascia denser ventrally and longer than setae on disc; (39) scutum as in female (16 above); (41) fasciae of mesepisternum indistinct; (42) axilla as in female (19 above); (43) metanotum as in female (20 above); (45) terga 1-4 with apical fasciae incomplete medially, apical fascia missing on tergum 5; gradular grooves on terga 4-6 with fasciae weak; gradular groove on tergum 2 almost obliterated medially; fovea on tergum 2 inconspicuous, shallow, about 0.05 mm long, 0.1 mm wide (Fig. 25E); (47) setae on gonocoxites not as copious as shown in Figure 26F.
HOST RECORDS. Medler and Koerber (1958) reported Coelioxys moesta to be a parasite of Megachile relativa; Medler (1959) recorded M. centuncularis as a host; and Medler and Lussenhop (1968) related that D. H. Pengelly reared C. moesta from the nests of M. texana and M. frigida. Hobbs (1968) noted C. moesta as a probable parasite of M. rotundata. A new host record is from an anonymous label on a pin with a female of C. moesta from Tucson, Arizona: M. concinna.
DISTRIBUTION AND SEASON OF FLIGHT. The distribution of Coelioxys moesta is practically the same as that of C. funeraria (compare Figs. 20 and 30).
Coelioxys moesta is in flight at least from May 27 (Virginia) to September 29
HABITAT. The habitat of Coelioxys moesta agrees closely with that of C. funeraria with both bees taken at many of the same localities, GEOGRAPHIC VARIATION. The variation in Coelioxys moesta described above does not seem to be related to geography.
COMPARATIVE, COMMENTS. Females of Coelioxys moesta are probably most easily confused with dark females of C. banksi but differ in that the profile of the clypeus is straight in C. moesta. Males of C. moesta are probably most easily confused with dark males of C. banksi but differ by the dorsal carina of the genal excavation which extends to the preoccipital carina in C. moesta. Both sexes of C. moesta differ from all others in this group by the prothoracic tubercles which are not produced into a thin, almost translucent carina. Axillae of both sexes are shorter than those of other species in this group. The prothoracic tubercles and axilla of C. moesta more closely resemble those of C. funeraria than those of other bees in the rufitarsis group. However, C. moesta possesses complete graduli on metasomal terga two and three (incomplete in C.