Megachile (Rhyssomegachile) urbana Smith

Gonzalez, Victor H., Griswold, Terry & Engel, Michael S., 2018, South American Leaf-Cutter Bees (Genus Megachile) Of The Subgenera Rhyssomegachile And Zonomegachile, With Two New Subgenera (Hymenoptera: Megachilidae), Bulletin of the American Museum of Natural History 2018 (425), pp. 1-73 : 1-73

Megachile (Rhyssomegachile) urbana Smith

Figure 14 , 20

Megachile urbana Smith, 1879: 76 (lectotype ♀, examined, BMNH 17A.2451: Santarém, Pará, Brazil).

DIAGNOSIS: This species is known only from the female lectotype. It shares with M. kartaboensis Mitchell a large body size (head width: 3.9– 4.0 mm), presence of carina behind gena only, short interocellar distance (<1.5× OD), fine punctation on clypeus and supraclypeal area, absence of apical fascia on terga, and presence of corkscrew-like setae on the ventral surface of the mesepisternum and fore- and middle legs. It can be easily recognized from that species, as well as from M. simillima , by the punctation of the mesoscutum, which is sparsely punctate on the disc, with punctures separated by 1.0–2.0× a puncture width (fig. 20D).

REDESCRIPTION: Lectotype, Female: total body length 11.5 mm; forewing length 8.8 mm; head width 4.0 mm. Head 1.3× wider than long; inner orbits of compound eyes parallel or nearly so; intertorular distance 1.4× torulorbital distance; interocellar distance 1.5× OD, 0.8× ocellocular distance; ocelloccipital distance 2.4× OD, 1.2× ocellocular distance; clypeus with distal margin entire, slightly incurved medially; scape 3.0× longer than broad, pedicel 1.2× longer than broad, F1 about as long as F2, slightly broader than long as in F2–F9, distalmost flagellomere longest, 1.6× longer than broad. Mesobasitarsus slightly broader and shorter than mesotibia.

Body color black, except dark reddish brown on legs, distal half of T1–T5, and sterna. Wings slightly brownish, darker on radial cell apically, first submarginal, and marginal cells; veins and pterostigma dark brown.

Pubescence brownish gray to dark brown, except white on: paraocular area inferiorly, sides of clypeus and supraclypeal area, base of mandible, gena, hypostomal area, anterior margin of mesoscutum, metanotum, sides of mesepisternum, metepisternum, propodeum, and S2–S5 except laterally. Ventral surface of mesepisternum and fore- and middle legs with coxae, trochanters, base of femora, and outer surfaces of tibiae and basitarsi densely covered by corkscrewlike setae (Fig. x). Discs of T2–T5 sparsely covered with short (~0.3× OD), appressed setae, laterally and on discs of T4 and T5 with scattered, longer, erect or semierect setae; T6 with shorter, denser appressed setae than on preceding terga, with scattered erect setae laterally.

Face and vertex coarsely and contiguously punctate, with surface among punctures angular on frons, rounded otherwise; clypeus and supraclypeal area smooth and shiny, with finer punctures than on vertex, punctures sparser (≤1.0× PW) and larger on disc of clypeus; upper gena with shallower, smaller punctures than on vertex, punctures stronger and closer on lower gena and hypostomal area; outer surface of mandible apically, above outer ridge, with carinae somewhat dull, minutely roughened. Pronotum weakly imbricate with smaller, shallower punctures than on mesoscutum; mesoscutum weakly imbricate, somewhat dull, punctures separated by 1.0–2.0× a puncture width on disc, contiguous or nearly so along margins; mesoscutellum and axilla dorsally as on disc of mesoscutum; mesepisternum smooth and shiny with larger (1.5×), sparser (1.0–1.5× PW) punctures than on mesoscutum, punctures becoming smaller and closer dorsally; metepisternum and propodeum imbricate, with oval, faint, and spaced (≤1.0× PW) punctures on metepisternum, about as large as those on mesoscutum; lateral surface of propodeum with smaller, fainter, closer punctures than on metepisternum, posterior surface of propodeum with widely separated (2.0–4.0× PW) punctures; metanotum finely and minutely (≤1.0× PW) punctate; legs weakly imbricate to smooth and shiny, coarsely and densely (≤1.0× PW) punctate, punctures larger and sparser on hind legs. Terga minutely and densely punctate, punctures contiguous or nearly so, at most separated by a puncture width; sterna strongly imbricate, coarsely punctate, punctures smaller and closer on basal sterna.

Figures

FIGURE 14. Collection localities for species of Megachile (Rhyssomegachile).

FIGURE 20. Female holotype of Megachile (Rhyssomegachile) urbana Smith. A. Facial view. B. Lateral habitus. C. Dorsal habitus. D. Detail of mesoscutum and mesoscutellum. E. Dorsal view of metasoma.