Cyrtopogon infuscatus Cole, 1919: 233.
Recognition characters: Black to blue-black species; length 8–12 mm; antennae black; mystax largely white in male, entirely black in female; thorax black, thickly gray pollinose, some black pile in front of wings; wings mostly infuscated; scutellum black, posterior margin and the central part of or the entire disc pollinose; abdomen blue-black with white pile, much longer on sides of segments 1–3, sides of first segment and posterior lateral margins of 2–5 white pollinose, 6–7 pollinose except at dorsal triangle; genitalia black, gray pollinose and short black pilose; legs entirely black, femora and tibiae with long white pile and black bristles, short golden pile beneath tarsi, on tips of hind tibiae and on all but base of front tibiae.
Distribution: Recorded from Wyoming by: Cannings (1994); Fisher & Wilcox (1997); Geller-Grimm (2018).
Habitat: Douglas fir forest and pine-douglas fir forest vegetation types.
Ethology: Nothing known.
Prey: None known.