Megachile (Litomegachile) coquilletti Cockerell, 1915

Bzdyk, Emily L., 2012, A revision of the Megachile subgenus Litomegachile Mitchell with an illustrated key and description of a new species (Hymenoptera, Megachilidae, Megachilini), ZooKeys 221, pp. 31-61 : 40-42

Megachile (Litomegachile) coquilletti Cockerell, 1915

Megachile mendica coquilletti Cockerell 1915: 535. Holotype male, USA: Texas (USNM).

Diagnosis.

Female Megachile coquilletti can be distinguished by the combination of a mandible with an even concavity in between teeth 3 and 4, and a slightly concave T6. It resembles Megachile gentilis , which has an angulation between teeth 3 and 4 of the mandible, and Megachile brevis , which has a much more concave T6 and much less black scopal setae on S6. Male Megachile coquilletti are easily distinguished from other Litomegachile by the foreleg with bicolored tarsomeres; the first 4 apical tarsomeres are yellow, contrasting with the darker basitarsus (Figure 4F). The males of all other species in the subgenus have uniformly brown foretarsi (Figure 4E).

Female. Body length11-12 mm. Mandible 4-toothed, with no angulation between teeth 3 and 4 (Figure 4A). T2-3 with deep transverse basal grooves, T4 with shallow groove. T1-5 with apical fringes of white hair that covers marginal zone; T1-2 with thin fringes of white hair, with white discal pubescence, T3-5 with black discal pubescence. T6 slightly concave in profile and laterally in dorsal view; with black appressed pubescence and black erect setae basally. S1-5 with ivory setae; S6 with some ivory setae basally, mostly black setae (Figure 5B).

Male. Body length9-12 mm. Mandible 3-toothed.Ocellocular distance less than ocelloccipital distance (Figure 4C). Foretarsus pale yellow, contrasting with darker basitarsus (Figure 4F). Head and mesosoma with white pubescence. T5 with apical fringe of white hair that covers marginal zone, interrupted medially. T6 with tomentum (Figure 6F); with transverse carina variable in shape, but usually with distinct medial notch and projections; true apical margin with submedial teeth closer to lateral teeth than each other (Figure 6B). Genitalia and hidden sterna shown in Figures 7B1-B4.

Variability.

Male tergal discal pubescence is variable in color. Some female specimens in fresh condition show a slight angulation between mandibular teeth 3 and 4. These may still be differentiated from Megachile gentilis by the lack of black setae on S5.

Distribution of material examined.

USA: California: El Dorado and Yolo Counties (Jun.-Aug.); Nevada: Clark, Humboldt and Lincoln Counties (May-Jul.); Texas: Fayetteville County (Sep.); Utah: Cache, Garfield and Washington Counties (May-Aug.); 42 females, 105 males.

Ecology.

Megachile coquilletti was collected in trap nests along the Cosumnes River south of Sacramento, California ( Thorp et al. 1992).

Flower records.

Asclepias speciosa ( Asclepiadaceae ), Cirsium vulgare ( Asteraceae ), Medicago sativa ( Fabaceae ), Polygonum aubertii ( Polygonaceae ), Salix sp. ( Salicaceae ), Salvia sp. ( Lamiaceae ), Solidago sp. ( Asteraceae ), Tamarix sp. ( Tamaricaceae ).

Comments.

M. coquilletti is a western North American species (Figure 9).