Comprehensive DescriptionRead full entry
General DescriptionThe duskywing skippers (genus Erynnis) can be a challenge to identify, particularly in prairie habitat where all three species may occur together. The white spots in the forewing tip are useful characters for separating these species: Persius and E. afranius both have at least two (usually three or four) spots, while the Dreamy Duskywing (Erynnis icelus) has only one spot or none at all. Persius and Afranius are more difficult to separate; Persius is more grey in colour, not brown, and the fore- and hindwing have contrasting grey (forewing) and grey-brown (hindwing) colours; Afranius is more evenly-coloured. Individuals from short-grass prairie habitat in August are almost certainly Afranius, since Persius does not have a second brood. Uncertain specimens must be dissected for diagnostic characteristics of the male genitalia; see Scott (1986) and Guppy & Shepard (2001) for illustrations. Layberry et al. (1998) attribute only subspecies borealis to the Alberta fauna, while Bird et al. (1995) assign northern and southern populations to subspecies borealis and fredericki, respectively.