Stelis occidentalis Parker and Griswold, 2013

Stelis occidentalis Parker and Griswold, 2013: 531 [♀, ♂].

     Holotype ♀. USA, Idaho, Owyhee County, Bruneau Sand Dunes, reared by F.D. Parker [rearing no. 27929B], from nest of Ashmeadiella aridula Cockerell [BBSL].

Taxonomic notes: Parker and Griswold (2013: 531) place this species in the coarctatus group (with Stelis coarctatus Crawford, 1916 and S. lamelliterga Parker and Griswold, 2013) which share a number of morphological features.

DNA Barcode Index Number (BIN): BOLD:AAP1974 [?]

This BIN is shared with the closely related Stelis coarctatus, which is typically more eastern in distirbution; the recent record of S. coarctatus from British Columbia by Sheffield and Heron (2019) may actually be S. occidentalis.

Biology: FD Parker (Parker and Griswold 2013) has reared specimens from vertically placed trap stems and block traps at 29 localities, including California, Arizona, Utah, Nevada, Idaho, and New Mexico. The most common hosts are member of the genus Ashmeadiella (82%). Specific hosts include: A. gillettei Titus (11); A. aridula (9); A. bigeloviae (Cockerell) (4); A. breviceps Michener (2), A. rufipes Titus (1); A. meliloti (Cockerell) (1) and Ashmeadiella spp. (3). In addition, S. occidentalis specimens were reared from cells of a related megachilid genus, Hoplitis, including H. bullifacies Michener (2), H. shoshone (Parker) (1), H. pygmaea (Timberlake) (1) and H. (Alcidamea) spp.

Distribution in Canada: Parker and Griswold 2013 [BC]; Sheffield and Heron 2019 [BC?].

Parker and Griswold (2013) indicated this species occurred in British Columbia, but did not provide a specific locality.