Aridefferia snowi (Hine)

Lavigne, Robert J. & Dennis, Steve, 2019, Robber flies (Insecta: Diptera: Asilidae) of Wyoming, USA with keys to genera and species, Zootaxa 4662 (1), pp. 1-126 : 35-36

Aridefferia snowi (Hine)

Erax snowi Hine 1919: 116 .

Recognition characters: Blackish species; length 13–18 mm; mystax white with few black bristles on oral margin; bristles and setae of mesonotum mostly black, postpronotal setae partly white, in males notopleural (presutural of authors) and supraalar setae partly white, in female postpronotal setae white and notopleural bristles reddish brown; merals black on male and white on female; scutellar setae and bristles of male black, of female mixed white and black; wings faintly yellowish hyaline; in males abdominal segments 5–7 silvery white pollinose with patch of black setae dorsally on tergites 2–4; in males lower arm of basistyle subequal in length to upper arm; legs with femora and tibiae black except basal 4th in males and basal 3rd in females brown.

Distribution: PLATTE: Guernsey State Park, 3 km W of Guernsey, 19 May 1963 ( RJL); 11 km N of Hartville on Manville Road, 19 June 1963 ( RJL). Recorded from Wyoming by: Lavigne & Dennis (1994); Lavigne et al. (1993) (both as Efferia snowi )

Habitat: Grama-needlegrass-wheatgrass and wheatgrass-needlegrass grassland vegetation types.

Ethology: Nothing known.

Prey: COLEOPTERA (see Lavigne & Dennis 1994, as Efferia snowi ).