Megachile (Argyropile) parallela Smith, 1853

Megachile parallela Smith, 1853: 191 . Pearce 2008: 51. Drons 2012: 58. Pearce et al. 2012: 101.

Megachile (Argyropile) parallela; Mitchell 1937b: 48. Mitchell 1943: 12; 1944: 132; 1962: 159. Butler 1965: 10. Hurd 1979: 2066. Ivanochko 1979: 303. Gonzalez and Griswold 2007: 3. Gonzalez 2008: 161. Scott et al. 2011: 54. Sheffield et al. 2011: 23. Kuhlman and Burrows 2017: 12. Reese et al. 2018: 21. Delphia et al. 2019a: 24. Sheffield and Heron 2019: 69. Engel 2020: 10.

Megachile (Argyropile) asterae Mitchell, 1943: 13 .

Diagnosis. The female of M. parallela can be identified by the upcurve at the apical end of S6, which extends past T6 (Fig. 7L) and the appressed white to yellow setae on T6. The male of M. parallela can be identified by the two pairs of prominent teeth on the apical margin of T6, (Fig. 9C) and large, semi-circular emargination of the pre-apical carina of T6.

Notes. This species is recorded from localities across Montana (Fig. 1Z). Photographs, a full morphological description, and notes on the biology of this soil-nesting species can be found in Sheffield et al. (2011).