Megachile gemula vancouveriensis Provancher, 1888

Megachile carbonaria Cresson, 1879: 208 [♀]. Preoccupied, not Megachile carbonaria Smith, 1853.

     Lectotype ♀, designated by Cresson (1916: 114). USA, Nevada [ANSP no. 2420].

*Megachile vancouveriensis Provancher, 1888: 424 [♂]. Synonymy by Mitchell (1935: 181).

     Lectotype ♂, desginated by Sheffield and Perron (2014: 143). CANADA, British Columbia, Vancouver [ULQC no. 1476].

Megachile cressonii Dalla Torre, 1896: 427. Replacement name for Megachile carbonaria Cresson, 1879. Synonymy by Mitchell (1935: 185), as a variety of Megachile gemula Cresson, 1878. New synonymy.

Megachile (Delomegachile) gemula var. fulvogemula Mitchell, 1935: 185 [♀]. New synonymy.

     Holotype ♀. USA, New Mexico, Cloudcroft, 18 June 1902 [ANSP no. 4166].

Megachile vandykei Cockerell, 1925: 205 [♀]. Synonymy of Megachile gemula cressonii Dalla Torre, 1896 by Mitchell (1937: 420). New synonymy.

     Holotype ♀. USA, California, Plumas Co., Meadow Valley, 5000-6000 ft., 21 June 1924, by E.C. Van Dyke [CAS no. 1665].

Taxonomic notes: Megachile vancouveriensis Provancher, 1888 is here recognized as a distinct subspecies of M. gemula Cresson, 1878 based on a distinct western geography and subtle morphological differences apparent in the female, both supported by DNA barcodes.

Cockerell (1913: 531) was the first to record M. vancouveriensis in the northwest United States (Olympia, Washington), and affiliated it with M. gemula Cresson, 1878 and M. albula Lovell and Cockerell, 1907. However, he thought that it was distinct from the eastern forms based on the pale hair present on tergum 3, with black hairs on present at the sides, and the hind tarsi ventrally with the hair fringe being pale orange, but black in M. gemula, and orange-fulvous in M. albula (Cockerell 1913: 531). He also indicated that M. albula likley represented an intermediate form between M. gemula and M. vancouveriensis.

Mitchell (1935: 185) indicated that M. cressonii Dalla Torre, 1896 (described from Nevada as Megachile carbonaria Cresson, 1879, but also found in Arizona and Washington) likely represented a western, melanistic form of M. gemula Cresson, 1878.

Titus (1906: 151) examined a specimen of Megachile vancouverensis Provancher (no. 1417) and redescribed it, though indicated that it was not even a specimen of Megachile Latreille, 1802; a different specimen, or at least a differently numbered specimen (ULQC no. 1476) was selected as the lectotype by Sheffield and Perron (2014: 143) to fix the name to this specimen and support the synonymy of Mitchell (1935: 181).

Mitchell (1935: 1985) also described the variety fulvogemula Mitchell, 1935 from New Mexico, though the paratype series included material from Washington and BC. In the discussion of this taxon, Mitchell (1935: 186) mentioned additional material from BC that also had the reddish (or partially reddish) scopal hairs, but the hairs of the clypeus dark, not pale as in the type materials. Recently collected materials on hand from BC support this. Mitchell (1935: 186) indicated that M. gemula of the west tend to have pale hair on the clypeus, while material from the east tend to have intermixtures of dark hair. While Ascher and Pickering (2023) list Megachile gemula var. fulvogemula as a possible synonym of M. melanophaea Smith, 1853, the specimens examined from BC support its placement with M. gemula (though the type material has not yet been examined).

Mitchell (1935) did not include Megachile vandykei Cockerell, 1925 in his revision of Delomegachile Viereck, 1916, though the description of the female, which indicated the entirely black pubescence is consistent with the description of M. carbonaria Cresson, 1879, supporting the synonymy of Mitchell (1937: 420).

DNA Barcode Index Number (BIN): BOLD:ACE9776

Distribution in Canada: Provancher 1888 [BC, as M. vancouveriensis Provancher]; Gibson 1917 [BC, as M. gemula Cresson, 1878]; Mitchell 1935b [BC, and as M. gemula fulvogemula Mitchell]; Buckell 1950 [BC, and as M. gemula fulvogemula Mitchell]; Sheffield et al. 2011 [BC, as M. gemula Cresson, 1878]; Sheffield and Heron 2019 [BC, as M. gemula Cresson, 1878].