The Dreamy Duskywing or Aspen Dusky Wing (Erynnis icelus) is a butterfly of the Hesperiidae family. It is found in boreal North America, from the Northwest Territories east across southern Canada to Nova Scotia, south in the western mountains to southern Arizona and southern New Mexico, south in the east to Arkansas, north-eastern Alabama and northern Georgia.
The duskywing skippers (genus Erynnis) can be a challenge to identify, particularly in prairie habitat where all three species may occur together. The Dreamy Duskywing can be separated from the other two species by the white spot near the forewing tip: icelus has either only one spot or none at all, while the other two duskywings (E. afranius and E. persius) have at least two (more often three or four) spots. The Dreamy Duskywing is also slightly smaller on average, with a wingspan of 25 to 30 mm. the forewing apex is more blunt in shape, giving icelus a more squared-off appearance than the other two duskywings.
Most of temperate North America, from the Mackenzie River valley, NWT south to Arizona / New Mexico and Georgia, but absent from much of the Great Plains states (Layberry et al. 1998, Opler 1999).
Widespread in clearings and meadows and woodlands near aspen woods.
Non-Migrant: No. All populations of this species make significant seasonal migrations.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Erynnis icelus Scudder & Burgess: Hesperiidae, Lepidoptera
(observations are from Robertson; this skipper is the Dreamy Duskywing)
Boraginaceae: Lithospermum canescens sn fq (Rb); Fabaceae: Astragalus crassicarpus trichocalyx sn np (Rb), Cercis canadensis sn np (Rb); Polemoniaceae: Phlox divaricata laphamii sn (Rb); Portulacaceae: Claytonia virginica sn (Rb); Scrophulariaceae: Collinsia verna sn np (Rb); Violaceae: Viola pedata sn (Rb)
Insect activities:
fq = frequent flower visitor (about 6 or more visits reported)
np = non-pollinating
sn = sucks nectar
Scientific observers:
(Rb) = Charles Robertson
No conservation concerns.