Extracted from: Sheffield C. S., et al (2011). Leaf cutter and Mason Bees of the Genus Megachile Latreille (Hymenoptera; Megachilidae) in Canada and Alaska. Canadian Journal of Arthropod Identification No. 18 |
Megachile (Megachiloides) anograe Cockerell, 1908
Megachile anograe Cockerell, 1908a. Ann. Mag. Nat. Hist. 8: 261 (♀).
Megachile laurita Mitchell, 1927. Psyche 34: 115 (♀). New synonymy.
Megachile laurita semilaurita Mitchell, 1927. Psyche 34: 116 (♀). New synonymy.
Megachile (Xeromegachile) alamosana Mitchell, 1934. Trans. Amer. Entomol. Soc. 59: 329 (♂). New synonymy.
Diagnosis. The female of M. anograe can be recognized by the combination of 3-dentate mandibles, relatively large body size (12-13 mm), and the shiny, sparsely punctate surface of T5 and T6 (with shiny interspaces of 3-4 pd). They are most similar to M. sublaurita and M. umatillensis. The female of M. sublaurita is generally smaller (9-10 mm), and has T5 and T6 more densely punctate. The female of M. umatillensis has a 4-dentate mandible. The male of M. anograe is recognized by the combination of conspicuously pale coloured and greatly modified front legs, a rounded postmedian tranverse carina on T6, and T5 lacking a white, apical fascia. They are most similar to M. sublaurita and M. umatillensis, and less so to M. fortis, M. wheeleri, M. manifesta, and M. subnigra, all of which have a white, apical fascia on T5.
Female: Length 12-13 mm.
Head. 1) compound eyes subparallel; lateral ocelli subequally distant from eyes and edge of vertex, 2) clypeal margin nearly straight, slightly thickened and narrowly impunctate medially, 3) mandible 3-dentate, the two apical teeth approximate, with a very long cutting edge between 2nd and inner tooth (Plate 1, Figure M19), 4) gena slightly wider than compound eye (9:7), 5) punctures fine and close on vertex and gena above, most of face below ocelli, and on clypeus basally, becoming more coarse in apical half of clypeus, more shallow and sparse on gena below, 6) pubescence entirely white on head, sparse on most surfaces, hardly concealing surface except around base of antennae, 7) F1 longer than broad (5:4) and longer than pedicel and F2, which is very slightly broader than long, remaining flagellomeres quadrate, apical flagellomere longer than broad (4:2.5).
Mesosoma. 1) pubescence relatively short, thin and entirely white, more elongate laterally and posteriorly, copious around pronotal lobe and at wing base, 2) punctures relatively coarse and close on mesoscutum and scutellum, with shiny interspaces present, especially medially on mesoscutum, scutellum with a thin but distinct impunctate area medially, punctures relatively coarse, deep and sparse on pleura, propodeum shiny with punctures fine and sparse, triangle shiny and impunctate, very slightly rugose along basal margin, 3) mid and hind basitarsi distinctly shorter and narrower than their tibiae, 4) tegula reddish, finely punctate, becoming more sparse in posterior half, 5) wings hyaline, very slightly clouded apically, the veins reddish-brown.
Metasoma. 1) T2-T5 very slightly depressed basally, with an indistinct carinate rim, and depressed somewhat apically; T6 triangular in dorsal aspect, narrowly subtruncate apically with the sides straight, straight in profile with abundant dark erect hair visible; all terga shining, punctures minute and close on T1 and T2, becoming increasingly sparse but also fine to T5 with shiny interspaces 3-4 pd in width, somewhat less sparse on T6; T1-T5 with white apical fasciae, dense on the more apical terga, narrower medially on the more basal ones, pubescence entirely white on T1 and T2, T3-T5 with dark hairs on apical half of disc; T5 and T6 with black pubescence laterally, 2) scopa white, entirely black on S5-S6 (most specimens); punctures fine and close on basal sterna, becoming coarse and more sparse apically, with shiny interspaces.
Male: Length 10-11 mm.
Head. 1) compound eyes subparallel; lateral ocelli subequally distant from eyes and edge of vertex, 2) clypeal margin slightly produced, shallowly emarginate medially, apical rim of emargination narrowly shiny and impunctate, 3) mandible 3-dentate, the 2nd tooth much closer to the apical tooth than the inner one, lower process triangular, acute, subbasal in position, 4) gena slightly wider than compound eye, 5) punctures fine, shallow, but rather close on gena, becoming deeper and more distinctly separated on vertex and between lateral ocelli and eyes, with shiny interspaces ≤ 1 pd, fine and close on face below median ocellus, including clypeus and supraclypeal area, fine interspaces shiny though hidden beneath dense pubescence, 6) pubescence entirely pale yellowish-white on head, dense and elongate on face below median ocellus, on clypeus and supraclypeal area, sparser but elongate on gena below, and medially on vertex, pubescence of vertex laterally and along upper margin of eye sparse, short, and erect, 7) F1 about as long as broad, slightly longer than pedicel, subequal in length to F2, which is quadrate, the remaining flagellomeres slightly longer than broad (4:3), apical flagellomere flattened and broadly dilated.
Mesosoma. 1) pubescence copius and entirely pale on dorsal surface, more elongate on propodeum, with dense white tufts at edges of pronotal lobe and behind wing base, pale on legs, the front tarsal fringe pale and long, with dark tipped hairs on the underside, mid tarsal fringe pale, long and conspicuous, 2) punctures fine and close, very slightly separated near centre of mesoscutum, more so on scutellum medially, and on pleura, propodeum with fine well spaced punctures, triangle smooth, shiny and impunctate, 3) front coxal spine narrowly triangular, broader at base, with a patch of reddish bristles on outer half of base, tip with a very small patch of pubescence, elongate, pale pubescence on posterior surface, coxal surface otherwise bare; front femur dark on outer surfaces, yellowish-brown above, otherwise yellowish with lower margin rounded and carinate, front tibia mostly yellowish, with small darker areas on outer face, apex yellowish, with a series of stiff, black bristles, front tarsus yellowish and slightly dilated, front basitarsus slightly narrower than its tibia, the anterior margin excavated, basal half of inner rim of excavation with dark, short bristles, tarsomeres 2-4 with a dark spot ventrally, mid and hind tarsi dark brown, hind basitarsus very short, less than half as long as its tibia, narrowed apically, outer surface of hind basitarsus shiny, with sparse, long pubescence, 4) tegula reddish-brown, shiny, finely and sparsely punctate, 5) wings subhyaline, the veins brownish-black.
Metasoma. 1) terga slightly depressed basally, basal margin of depression slightly carinate, terga more deeply depressed apically; carina of T6 entire, slightly irregularly crenulate, produced medially into a rounded to broadly triangular point that points downward, the apical margin with pronounced carinate median teeth, the lateral teeth small but distinct; T7 conspicuous, produced medially into an acute spine; punctures minute, shallow and close (≤ 1 pd) on basal terga, but becoming very sparse on the shining, more apical terga, T6 shining, sparsely punctate; pubescence sparse and entirely dark brown to black on discs of T3-T6, copious and entirely pale on T1 and T2, complete, but sparse white apical fasciae on T1-T4, T5 lacking fascia, 2) S1-S4 visible, apical margins depressed and hyaline, discs shiny and sparsely punctate.
Genitalia. Plate 2, Figure G19.
Discussion. This species is uncommon in southern Alberta, and Hobbs and Lilly (1954) thought it too rare to be an important alfalfa pollinator. Melanistic forms (i.e., Megachile laurita, M. laurita semilaurita) occur in the western United States, though have not been recorded from Canada. Megachile laurita and M. laurita semilaurita show no divergence in CO1 sequence from M. anograe collected throughout its range, and other than the completely black scopa (and dark pubescence in other areas), show no other morphological differences from M. anograe and are thus placed into synonymy. The type specimens of the newly synonymised species were examined. This species nests in the ground (Table 1).
Distribution: Southern AB, east of the Rocky Mountains (see Map 19).