Megachile (Rhyssomegachile) simillima Smith
Creators: name: Gonzalez, Victor H.
name: Griswold, Terry
name: Engel, Michael S.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Megachilidae
Megachile
Megachile simillima

description: Megachile (Rhyssomegachile) simillima Smith
Figures 1, 4A, 14, 17–19
Megachile simillima Smith, 1853: 185 (holotype ♀, examined, BMNH 17A.2456: Pará, Brazil). Moure et al., 2007: 991 (placement in Rhyssomegachile Mitchell).
Megachile cara Mitchell, 1930: 263 (neotype ♂ [here designated], NCSU 0020754: Buenavista, Bolivia). Mitchell, 1943: 668 (placement in Ptilosarus Mitchell).
Megachile stabilis Mitchell, 1930: 298 (neotype ♀ [here designated], NCSU 0005853: Buenavista, Bolivia). Raw, 2002: 33 (placement in Rhyssomegachile Mitchell).
DIAGNOSIS: The female of this species can be easily recognized by the following combination of features: preoccipital carina behind gena only; mesoscutum with contiguous punctures on disc, surface among punctures angular (fig. 4A); ventral surface of mesepisternum and fore- and middle legs with coxae, trochanters, femora, and outer surfaces of tibiae and basitarsi covered by thick, minutely branched, and apically curved setae (fig. 17C); T2–T5 each with apical fasciae at least laterally (fig. 17E); T6 covered mostly by short, appressed yellowish setae from which scattered, longer, erect setae arise. The male can be recognized by following combination of features: mesoscutum imbricate, with contiguous or nearly so, coarse punctures on disc; procoxa without spine; metafemur without a keirotrichial patch on its posterosuperior surface; metabasitarsus elongate, about 3.7× longer than broad, with short setae along its anterior margin, at most as long as maximum basitarsal width. The female of this species resembles that of M. kartaboensis in the coarse, contiguous punctation of the mesoscutum. It can be distinguished from that species by its smaller body size, the ventral surface of the mesepisternum and fore- and middle legs covered by thick, apically curved setae (corkscrew-like setae covering these structures in M. kartaboensis), and the coarser punctation on the clypeus and supraclypeal area. Also, the interocellar area is greater in M. simillima (2.1× OD) than in M. kartaboensis (1.3× OD).
REDESCRIPTION: Female: total body length 9.3 mm; forewing length 6.9 mm; head width 3.3 mm. Head 1.3× wider than long; inner orbits of compound eyes parallel or nearly so; intertorular distance 1.6× torulorbital distance; interocellar distance 2.1× OD, slightly shorter than ocellocular distance; ocelloccipital distance 2.6× OD, 1.2× ocellocular distance; clypeus with distal margin sinuous, slightly incurved medially; scape 3.2× longer than broad, pedicel slightly longer than broad, F1 about as long as F2, slightly broader than long as in F2–F9, distalmost flagellomere longest, 1.5× longer than broad. Mesobasitarsus narrower, shorter than mesotibia; metatibia 2.4× longer than broad; metabasitarsus 2.9× longer than broad, shorter (0.7×) and narrower (0.9×) than metatibia.
Body color black, except dark reddish brown on outer surface of mandible apically, legs, tegula, and basal sterna. Wings slightly brownish, darker on radial cell apically, first submarginal, and marginal cells; veins and pterostigma dark brown.
Pubescence predominantly white except: vertex, discs of mesoscutum and mesoscutellum, inner surfaces of tarsi, and S6 with brownish setae; discs of T1–T4 with short, dense, appressed, dark brown to black setae, discs of T5 and T6 with short, dense, appressed yellowish setae and longer, scattered, erect to semierect setae; apical margins of T2–T5 laterally with yellowish fasciae. Ventral surface of mesepisternum and all legs distinctly covered by thick, minutely branched, and apically curved setae.
Face and vertex coarsely and contiguously punctate with surface among punctures angular, except clypeus, supraclypeal area, and vertex with sparser (≤0.5× PW) punctures, surface among them rounded, smooth and shiny; gena with shallower punctures than on vertex, punctures stronger, smaller, closer on lower gena and hypostomal area than on upper gena; outer surface of mandible apically, above outer ridge, with carinae smooth and shiny. Pronotum weakly imbricate with smaller, shallower, sparser (≤1.0× PW) punctures than on mesoscutum; mesoscutum as on frons; discs of mesoscutellum and axilla with sparser punctures than on mesoscutum, surface among them rounded; mesepisternum smooth and shiny with larger (1.5×), sparser (≤1.0× 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 metepister- num, about as large as those on mesoscutum; lateral surface of propodeum with smaller, closer, fainter punctures than on metepisternum, posterior surface of propodeum with widely separated (2.0–4.0× PW) punctures, propodeal triangle strongly imbricate to minutely rugulose; metanotum minutely rugulose with small, scattered (2.0– 3.0× PW) punctures; legs weakly imbricate to smooth and shiny among coarse, dense (≤1.0× PW) punctures, punctures sparser on femora. Terga weakly imbricate to smooth and shiny, with smaller (0.5×), sparser (1.0–2.0× PW) punctures than mesoscutum, punctures most sparse on disc of T1, denser on apical terga; sterna strongly imbricate, coarsely punctate, punctures smaller and closer on basal sterna.
Male: As described for the female except for the usual secondary sexual characters and the following: total body length 8.0 mm; forewing length 6.3 mm; head width 3.1 mm. Inner orbits of compound eyes converging below; intertorular distance 2.2× torulorbital distance; interocellar distance 1.8× OD, shorter (0.8×) than ocellocular distance; ocelloccipital distance 2.3× OD, about as long as ocellocular distance; scape 2.1× longer than broad, pedicel about as long as F1, each about as long as broad, F2 1.5× longer than F1, longer than broad as remaining flagellomeres, distalmost flagellomere longest, apically flattened, not expanded. Procoxa unmodified, without spine; metafemur without a keirotrichial patch on its posterosuperior surface; metabasitarsus elongate, about 3.7× longer than broad. T6 with preapical carina sometimes weakly crenulated. Genital capsule and associated terga and sterna as in figure 19.
Pubescence longer and denser than the female; clypeus sparsely covered by setae (integument largely visible among setae) on basal two thirds, densely covered by setae (integument not visible among setae) on apical one third. Meso- and metabasitarsus with short setae along anterior margin, at most as long as maximum basitarsus width.
Punctation coarser than in female; T4 and T5 with depressed, smooth, shiny, brown apical margins.
HOLOTYPE (M. simillima): ♀, Type/5/4/? [illegible]/ B.M. Type Hym. 17a.2456/ simillima Type Sm/ Megachile simillima Type. Sm. (BMNH). The holotype of M. simillima is in relatively good condition, except for some hyphae sparsely covering the head and mesosoma, left F1–F6 missing, and T6 and S6 slightly pushed inside the metasoma.
NEOTYPE (M. cara, here designated): ♂, Buenavista, Dep. Sta. Cruz, Bolivia, 450 m. h./ QR barcode NCSU 0020754/ ♂ Megachile cara Mitchell, Paratype (greenish label)/ ♂ Neotype Megachile cara Mitchell, Des. V.H. Gonzalez, M.S. Engel, & T. Griswold 2016 (NCSU). Megachile cara Mitchell was described from three male specimens whereas M. stabilis Mitchell from six female specimens, all from the same locality. The holotypes of both species were lost during World War II (see Material and Methods, above), and to stabilize these names, we herein designate as neotypes one of the paratypes of each species.
NEOTYPE (M. stabilis, here designated): ♀, Buenavista, Dep. Sta. Cruz, Bolivia, 450 m. h. / (Rhyssomegachile) simillima Sm. as det. 1982 in T.B. Mitchell collection/QR barcode NCSU 0005853/ Megachile stabilis Mitchell, Paratype / ♀ Neotype Megachile stabilis Mitchell, Des. V.H. Gonzalez, M.S. Engel, & T. Griswold 2016 (NCSU). See above (neotype for M. cara) for discussion of type series for M. stabilis.
ADDITIONAL MATERIAL EXAMINED (n = 26♂♂, 78♀♀): Argentina: 1♀, Arg. [Argentina], Misiones, Puerto Esperanza, Fritz, XII.76 [December, 1976] (AMNH). Bolivia: 1♀, Bolivia, Guanay, Uyapi-X-95, Gerlach /AMNH_ BEE 000210951 (AMNH); 1♀, Bolivia: La Paz Prov. Uyapi / Guanay, Nov. 1998, A. Ugarte Peña (AMNH); 1♀, La Paz: Guanay, 10-XI-1992, Luis Peña /AMNH_BEE 00021096 (AMNH); 1♀, Buenavista, Dep. Sta. Cruz, Bolivia, 450 m. h./ NCSU 0005852 / Megachile stabilis Mitchell, Paratype (NCSU); 1♀, Bolivia-Pto. Fon Beni, Beni, 12 Nov. 1956 (L. Pena)/ SEMC 1204252 (SEMC). Brazil: 2♀♀, Acre, Iquiri, 24 August 1951 / SEMC 1205351, -57 (SEMC); 9♀♀, 3♂♂, Tefé, Amazonas, Brasil, IX-1959, R. Carvalho / Coleção Campos Seabra / NCSU 0004708–16, 0020755, -57, -58, (NCSU); 1♂, ut supra, VIII- 1959 / NCSU 0020756 (NCSU); 19♂♂, Brasil, Rio Jaravi, Estirao do Equador [Amazonas], Alvarenga, X. 79 [1979] (AMNH); 5♀♀, Jacareacanga, Pará, Brasil, X-1959, M. Alvarenga leg./ NCSU 0004723–27; 1♀, ut supra, July 1969, F. Barbosa (AMNH); 1♀, Brasil: Paraná, Bituruna, 25–30 Jan 1956, V. Stawiarski / SEMC 1205299 (SEMC); 2♀♀, Porto Cabral, Rio Paraná, Travassos Filho o. [Brazil]/ NCSU 0004721, -22/(NCSU); 1♀, ut supra (AMNH); 24♀♀, Brasil: Guapore, Abunã, Nov. 62 (W. Bokermann)/ SEMC 1184304–05, 1204881–83, 1204886, 1204887, 1204889, 1204890, 1204900, 1204901, 1204907, 1204908, 1204910–14, 1204916–19, 1204921, 1204923 (SEMC); 4♀♀, 1♂, Porto Velho, Guaporé, Brasil, XI-1954, M. Alvarenga, Dente, F. Pereira e Werner /Coleção Campos Seabra / SEMC 1178755–58 (SEMC); 9♀♀, 1♂, ut supra, NCSU 0004399, 0004400, 0004701–07, 0020759 (NCSU); 3♀♀, Sao Carlos, Matto Grosso, Porte Velhos, Brazil, Sep. 9 1943, Mark Taylor / NCSU 0004718–20 (NCSU); 1♀, Mato Grosso: Sinop, October 1976, M. Alvarenga /AMNH_BEE 00021097 (AMNH); 1♀, St. Paulo / NCSU 0004728 (NCSU); 1♀, 56 43/ NCSU 0004398 (NCSU). Colombia: 1♀, Colombia, Amazonas, Parque Nacional Natural Amacayacu, at junction of Matamata stream with Rio Amazonas, F. Fernandez / AM 7-13/ CM 177/ SEMC 1184310 (SEMC); 3♀♀, ut supra, 2 km above mouth Rio Amazonas, 4 October 1998, Fernando Fernandez / SEMC 1184307–09 (SEMC). Ecuador: 1♀, Ecuador, Napo Prov., Yasuni National Park, Est. La Catolica; Nov. 7–15, 1998, DRoubik No. 83 (BBSL). Peru: 3♀♀, 1♂, Peru, Madre de Dios, Pakitza Bio. Sin., Reserved Zone, Manu National Park, 317 m, 11°56′41″S, 71°17′0″W, 16 Oct 2000; R. Brooks, PERU 1B00 008, ex: wet area near stream/SM0255992, 0256004, 0256014, 0255775 (SEMC); 1♀, Madre de Dios: Loromayo, on Inambari R., in low forest area, IX-10-1962 / L.E. Pena collector (AMNH); 3♀♀, Middle Rio Ucayali, Peru, X-27-23 [October 27, 1923], F6116/ H. Bassler Collection, Acc. 33591 (AMNH); 2♀♀, ut supra, XII-8-24 [December 8, 1924], F6174 (AMNH). Venezuela: 2♀♀, Venezuela, Terr. Federal Amazonas, Rio Cantaniapo at Las Paras / 23 January 1989, J.T. Polhemus, #CL2377/ex. wet sand seeps/ SEMC 1184311–12 (SEMC).
DISTRIBUTION: Argentina (Misiones), Bolivia (La Paz, Santa Cruz), Brazil (Pará, Rio Grande do Sul), Colombia (Amazonas), Ecuador (Napo), Peru (Madre de Dios), Venezuela (Amazonas) (fig. 14). This species appears to occur primarily in tropical rainforests and thus records from Mendoza, Argentina (Moure et al., 2007) need to be confirmed.
description: Published as part of 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), pp. 1-73 in Bulletin of the American Museum of Natural History 2018 (425) on pages 1-73, DOI: 10.1206/00030090-425.1.1, http://zenodo.org/record/4613364