Pogonioefferia dubius (Williston)
Erax, n. sp. ( dubius in key) Williston, 1885: 68.
Recognition characters: Grayish species; length 21 mm; mystax yellow; thorax gray pollinose, most of the dorsal setae and bristles black, laterally white; scutellum with white setae and black bristles on the margin; wings hyaline, very slightly darkened at the extreme apex; abdominal segments 1–4 with long white setae that are parted on the middle and directed outward on segments 2–4, segment 5 and remaining segments white and with very short white setae; male abdominal segments 1–2 conspicuously darker; femora black, tibiae and tarsi yellowish red to red except tips of the tibiae.
Distribution: Recorded from Wyoming by Cole (1969) (as Efferia dubia); Geller-Grimm (2018); Hine (1919) (as Erax dubius); Martin & Wilcox (1965) (as Efferia dubia).
Habitat: Pine-douglas fir forest (clearings within the forest where shrubs and grasses are dominant), sagebrush steppe shrub and grassland, and grama-needlegrass-wheatgrass and grama-buffalo grass grassland vegetation types.
Ethology: Nothing known.
Prey: None known.