Pallicephala occidentalis (Cole)

FIGURES 14–19. Representative habitats of species documented in this paper. Fig. 14. The unglaciated British Mountains west of the Firth River, Yukon, showing steppe grasslands and arctic tundra at the northern limit of trees in Canada. Dialineura gorodkovi and Psilocephala vicina have been collected here. Photo by Sydney Cannings. Fig. 15. Sand dunes at Bennett Lake, Carcross, Yukon, habitat for a diverse therevid fauna, including Cliorismia bussi, Dialineura gorodkovi, Pallicephala occidentalis, Pandivirilia conspicua, Psilocephala vicina, Spiriverpa albiceps, Thereva foxi, and T. utahensis. Photo by Sydney Cannings. Fig. 16. Tabuda planiceps habitat at Vaseux Lake, British Columbia; Pinus ponderosa trees with Purshia tridentata (green-leaved shrub) and Artemisia tridentata (grey shrub) in foreground. Photo by Robert Cannings. Fig. 17. Mount Kobau, British Columbia; view south to Osoyoos Lake.The grassland and subalpine slopes of this locality are home to Tabuda planiceps and at least four species of Thereva: T. aurofasciata, T. cingulata, T. fucata, and T. utahensis. Photo by Robert Cannings. Fig. 18. Upper beach at Cape Cook Lagoon, Brooks Peninsula, northwestern Vancouver Island, British Columbia—the only known Canadian locality for Thereva elizabethae. Photo by Robert Cannings. Fig. 19. The lower, south-facing grassland slopes of Nares Mountain, overlooking Nares Lake, Carcross, Yukon. Home of Thereva foxi and T. webbi. Photo by Sydney Cannings.

FIGURES 14–19. Representative habitats of species documented in this paper. Fig. 14. The unglaciated British Mountains west of the Firth River, Yukon, showing steppe grasslands and arctic tundra at the northern limit of trees in Canada. Dialineura gorodkovi and Psilocephala vicina have been collected here. Photo by Sydney Cannings. Fig. 15. Sand dunes at Bennett Lake, Carcross, Yukon, habitat for a diverse therevid fauna, including Cliorismia bussi, Dialineura gorodkovi, Pallicephala occidentalis, Pandivirilia conspicua, Psilocephala vicina, Spiriverpa albiceps, Thereva foxi, and T. utahensis. Photo by Sydney Cannings. Fig. 16. Tabuda planiceps habitat at Vaseux Lake, British Columbia; Pinus ponderosa trees with Purshia tridentata (green-leaved shrub) and Artemisia tridentata (grey shrub) in foreground. Photo by Robert Cannings. Fig. 17. Mount Kobau, British Columbia; view south to Osoyoos Lake.The grassland and subalpine slopes of this locality are home to Tabuda planiceps and at least four species of Thereva: T. aurofasciata, T. cingulata, T. fucata, and T. utahensis. Photo by Robert Cannings. Fig. 18. Upper beach at Cape Cook Lagoon, Brooks Peninsula, northwestern Vancouver Island, British Columbia—the only known Canadian locality for Thereva elizabethae. Photo by Robert Cannings. Fig. 19. The lower, south-facing grassland slopes of Nares Mountain, overlooking Nares Lake, Carcross, Yukon. Home of Thereva foxi and T. webbi. Photo by Sydney Cannings.