Megachile (Sayapis) pugnata Say, 1837

Megachile pugnatus Say, 1837: 408 .

Megachile (Sayapis) pugnata; Mitchell 1937c: 201; 1962: 179. Butler 1965: 14. Hurd 1979: 2072. Ivanochko 1979: 316. Fultz 2005: 134. Gonzalez 2008: 36. Scott et al. 2011: 56. Sheffield et al. 2011: 67. Kuhlman and Burrows 2017: 13. Reese et al. 2018: 22. Delphia et al. 2019a: 25. Sheffield and Heron 2019: 70. Engel 2020: 11.

Eumegachile (Sayapis) pugnata (Say); Mitchell 1980: 51.

Megachile pugnata; Drons 2012: 58.

Megachile inimica, not Cresson, 1872 (misidentification); Pearce 2008: 51. Pearce et al. 2012: 101.

Diagnosis. The female of M. pugnata can be identified by its parallel-sided tergites (Fig. 6C), pronounced tooth on the posterior genal margin (Fig. 7P), and clypeal margin with three tubercles. The genal tooth of the female cannot be mistaken for any other Montana Megachile species. The male of M. pugnata can be identified by its thin and narrowly pointed procoxal spine (Fig. 8H) and the scoop-shaped dilation of its probasitarsus, which has dark setae along the basal ⅓ of the posterior edge. The males are most similar to M. fidelis (see M. fidelis above).

Notes. This large, distinctive species is widespread in Montana, although most records are from the west (Fig. 1 AC). The fact that records extend to the southeast border indicates it will be found more broadly with more collecting in the under-sampled eastern part of the state. Photographs, a full morphological description, and notes on the biology of this cavity-nesting species can be found in Sheffield et al. (2011), who report that it is a Helianthus specialist. The voucher for the misidentified specimen (Pearce et al. 2012) is in the MTEC identified as a male M. pugnata (MTEC 57005) (Table 2; Supp. Material 2: Erroneous Records).