Montana Field Guide

[From Ferris and Brown 1981; Scott 1986; Layberry et al. 1998; Opler and Wright 1999; Glassberg 2001] Forewing 1.4-1.6 cm. Forewings rounded. Uppersurface of male yellow-orange with irregular black borders, lacks stigma; female in two forms:(1) similar to male but orange duller and less extensive (most common), (2) purple-black with a few clouded white spots on forewing (Pocahontas form). Undersurface of males and most females with extensive brown patch at hindwing base and broad brown borders enclosing yellow postmedian area; undersurface of Pocahontas hindwing purple-black, with pattern obscure.

One flight, mostly June to early July in the Rocky Mountain region and northward, late April through May in the southeastern US (Scott 1986). Mid-May to early July in the west (Glassberg 2001). Mid-May to late July in Canada (Layberry et al. 1998). Mid-May to early July in Colorado (Scott and Scott 1978; Ferris and Brown 1981), June in western Nebraska (Johnson and Nixon 1967), late May to early July in North Dakota (McCabe and Post 1976).

Best determined by a combination of uppersurface yellow-orange to orange with irregular dark-brown to black borders, male stigma absent, undersurface of hindwing with extensive brown patch at hindwing base and broad brown borders enclosing yellow postmedian area; undersurface of female Pocahontas hindwing purple-black, with pattern obscure.

Non-migratory.

Woodland openings and edges, dense oak-ponderosa pine-Poa woodland, bog edges, streamside and trail openings, city parks (Scott and Scott 1978; Ferris and Brown 1981; Scott 1986; Layberry et al. 1998; Opler and Wright 1999; Glassberg 2011). Habitat in Montana not described but probably similar, and includes riparian woodlands and riverine parks (FLMNH Lepidopterists' Society database).

Larval food plants are grasses, including Panicum and Poa, possibly Bromus (Scott 1986, 2006; Layberry et al. 1998). Adults feed on flower nectar (including Allium, Apocynum, Arabis, Asclepias, Centaurea, Chrysanthemum, Echium, Fragaria, Geranium, Glechoma, Hedysarum, Hesperis, Hieracium, Iris, Lamium, Lathyrus, Ledum, Ligustrum, Lonicera, Lythrum, Nepeta, Phlox, Rubus, Sonchus, Symphyotrichum, Syringa, Taraxacum, Tradescantia, Trifolium, Verbena, Vicea), bird dung, and mud (Tooker et al. 2002; Scott 2014).

Limited information. Females lay eggs singly on or near host plant. Larvae feed on host plant leaves, overwinter (diapause) as egg, larva, possibly pupa (Ferris and Brown 1981; Scott 1979; 1986). Males perch throughout day 1-2 m above ground on vegetation in gullies and valley bootoms in clearings, awaiting passing females (Ferris and Brown 1981; Scott 1975b, 1986; Layberry et al. 1998).