Montana Field Guide

[From Ferris and Brown 1981; Scott 1986; Layberry 1998; Opler and Wright 1999; Glassberg 2001; Pyle 2002] Forewing 1.2-1.3 cm. Small, forewing slightly rounded. Uppersurface of forewing drab olive with tawny-orange along costal margin invading end of cell, male stigma sinuous in 3 segments with interior tan felt, male scale patch outside stigma connects with dark wing margin, hindwing unmarked drab olive; undersurface of hindwing brassy orange-brown or gray, sometimes with postmedian band of pale spots.

One flight, mid-June through July northward and in the Rocky Mountains, several flights, June to August at lower elevation and in the East, all year in Florida (Scott 1986). Mainly June and July in one brood areas, May to September in two brood areas (Glassberg 2001). Early June to late July across Canada (Layberry et al. 1998). Late May to August in the Rocky Mountain states (Ferris and Brown 1981). Mid-June to late August in Colorado (Scott and Scott 1978), mid-May to early August in Nebraska (Johnson and Nixon 1967; Dankert and Nagel 1988), mid-June to late July in North Dakota (McCabe and Post 1976), late May to early August in Washington (Pyle 2002), early June to late July in British Columbia (Threatful 1988; Guppy and Shepard 2001).

Best determined by a combination of small size, upersurface of forewing drab-olive with contrasting orange along costal margin, the male forewing stigma in 3 segments, hindwing unmarked; undersurface of hindwing orange-brown to gray and usually unmarked (sometimes with postmedian band of pale spots).

Non-migratory.

Montane meadows, lawns, pastures, vacant lots, roadsides, dry and wet native prairie, marsh and pond margins (Clench 1967; Ferris and Brown 1981; Scott 1986; Dankert and Nagel 1988; Threatful 1988; Layberry et al. 1998; Opler and Wright 1999; Glassberg 2001; Guppy and Shepard 2001; Pyle 2002). More abundant in midwestern native prairie than old fields and barrens (Swengel and Swengel 2015). Habitat in Montana not described but probably similar.

Larval food plants are grasses, including Dichanthelium, Digitaria, Glyceria, Koeleria, Panicum, and Poa, and sedges, including Carex; also Cynodon in captivity (Ferris and Brown 1981; Scott 1986, 1992, 2006; Layberry et al. 1998; Guppy and Shepard 2001; Pyle 2002; Warren 2005; James and Nunnallee 2011). Adults feed on flower nectar (including Apocynum, Asclepias, Astragalus, Bidens, Boltonia, Buddleja, Carduus, Centaurea, Centranthus, Cephalanthus, Chrysanthemum, Cirsium, Convolvulus, Coreopsis, Cornus, Dalea, Delphinium, Echinacea, Erigeron, Eryngium, Eupatorium, Gomphrena, Hedysarum, Helenium, Helianthus, Heliopsis, Iris, Jamesia, Lespedeza, Liatris, Linaria, Lobelia, Lupinus, Lychnis, Lycopus, Lythrum, Medicago, Melilotus, Monarda, Oenothera, Oxypolis, Oxytropis, Pastinaca, Phacelia, Phlox, Phyla, Polygonum, Prunella, Pycnanthemum, Rubus, Rudbeckia, Sagittaria, Salvia, Sedum, Silphium, Stachys, Symphoricarpos, Tagetes, Taraxacum, Trifolium, Verbena, Veronica, Vicea, Zinnia) and mud (Bray 1994; Reed 1997; Tooker et al. 2002; Scott 2014).

Females lay eggs singly on or near host plant on the undersides of leaves (Scott 1986, 1992). Eggs hatch in 9 days (depending on temperature), develop to L3 instar in about 35 days (depending on temperature) while most develop to L5 instar and pupae in about 40 days post egg-hatch, diapause (overwinter) as pupae although half-grown (L3 instar) larvae may overwinter in some situations, adults eclose (emerge from pupae) in about 10 days (James and Nunnallee 2011). Larvae eat host plant leaves, build nests of dead and live grass tied with silk, pupate in a stronger nest on ground or a base of grass, overwinter as pupae or half-grown larvae (Scott 1979, 1986, 1992; James and Nunnallee 2011). Males perch throughout the day in grassy swales, depressions in lawns, valley bottoms, awaiting passing females (Scott 1975b, 1986).