Erynnis persius

The 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.

The Persius Skipper occurs in western North America in a broad band from Alaska and northeastern Quebec south to California, Arizona and New Mexico. There are a series of populations disjunct from the western populations, occurring from the western Great Lakes region east to the Atlantic seaboard (Layberry et al. 1998, Opler 1999). The disjunct western and eastern populations, and the apparent differences in foodplants, suggest the taxonomy of these populations warrants further research.

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Forest edges and clearings, meadows and woodlands. Restricted to river valleys in the prairies.

Comments: A diverse group of ecologically different populations most of which would now be referred to subspecies BOREALIS. Habitats vary westward but eastward (subspecies PERSIUS) mostly in barrens or savannas, but a few eastern collections in boggy places. Habitat also made unclear by the abundant erroneous records in older literature and uncertainty about foodplants in some areas.

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.

Vetch (Astragalus sp.) is the presumed larval food plant in southwestern Alberta, based on female egg-laying observations (Bird et al. 1995). Lupines (Lupinus spp.) are suspected hostplants in Ontario (Layberry et al. 1998) and BC (Guppy & Shepard 2001). Adults take nectar at locoweed (Oxytropis spp.) and golden bean (Thermopsis rhombifolia) in Saskatchewan (Hooper 1973).

Comments: East of the prairies the usual food is LUPINUS PERENNIS but BAPTISIA TINCTORIA is used in Pennsylvania and probably Massachusetts. Farther west several genera of legumes are used. Reports of willows and poplars from several parts of range may refer mostly to misidentified ICELUS in the late 1800s. However, use of these plants cannot be ruled out. Note though Layberry et al. (1998) cold not verify such reports even for Canada where willow would seem most plausible.

The flight of the single annual brood peaks in late May to early July, depending on habitat.

Comments: Except in some parts of California one brood only, mostly in May-early June southward including Great Lakes region and New England. As late as July-early August in some boreal regions of Canada.

The egg is pale yellow at first, turning orange as it matures (Bird et al. 1995). Larvae are pale green with a dark dorsal line and a dark brown head, and the pupa is pale-spotted and dark green (Bird et al. 1995). Males perch to await females (Bird et al. 1995). The use of willows and poplars as larval hosts is unusual given the preference for legumes elsewhere, and these host records appear to be restricted to New England populations (Guppy & Shepard 2001). There is no evidence that western populations feed on plants in the willow family (Salicaceae) (Hooper 1973, Guppy & Shepard 2001).

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 46
Species With Barcodes: 1

No obvious concerns.

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure