Montana Field Guide

[From Ferris and Brown 1981; Scott 1986; Opler and Wright 1999; Glassberg 2001; Pyle 2002] Forewing 1.4-1.5 cm. Face and top of thorax golden-orange to gold-green, undersurface of head, front legs, thorax often white, wing fringes brownish, wings pointed. Uppersurface violet brown or dark brown all over, male with black stigma, female forewing with up to two tiny diffuse white spots near center, the inner spot half moon-shaped.

One flight, mostly July in the north and west, June in southern California; two flights in the southeast, late may to early September; many flights in Florida, March to December (Scott 1986). One brood areas, mid-May to early September; two brood areas, May through September (Glassberg 2001). Late June to mid-August in Canada (Layberry et al. 1998). Mid-June through July in the Rocky Mountain states (Ferris and Brown 1981). Early June to late August in Colorado (Scott and Scott 1978; Scott and Epstein 1987), late June to early August in western Nebraska (Johnson and Nixon 1967), late June to late August in North Dakota (McCabe and Post 1976), late May to early September in Oregon and Washington (Pyle 2002; Warren 2005), late June to mid-August in British Columbia (Guppy and Shepard 2001).

Best determined by a combination of pointed wings, overall dark brown, face and top of thorax golden-orange to gold-green, uppersurface of male with black stigma, female forewing with up to two tiny diffuse white spots near center, the inner spot half moon-shaped.

Non-migratory.

Moist areas along streams, roadsides, marshes, prairie, swales, seeps, open woodlands, woodland edges (Scott 1986; Opler and Wright 1999; Glassberg 2001; Pyle 2002); most commonly associated with undisturbed and lesser disturbed sites (Reed 1997; Hogsden and Hutchinson 2004), also occupies marshes dominated by introduced sedge (Catling and Kostiuk 2014). Habitat in Montana not described but probably similar.

Larval food plants are members of the Cyperaceae (sedges) in the genus Carex (several species), also reported using Cyperus in captivity (Heitzman 1964; Scott 1986, 1992, 2006; James and Nunnallee 2011). Adults feed on flower nectar (including Agastache, Anemone, Apocynum, Asclepias, Astragalus, Calylophus, Camerion, Carduus, Ceanothus, Cirsium, Dianthus, Erigeron, Eriogonum, Euphorbia, Galium, Gaura, Geranium, Grindelia, Hedysarum, Heterotheca, Jamesia, Lathyrus, Lupinus, Marrubium, Medicago, Melilotus, Mentha, Monarda, Penstemon, Phacelia, Prunella, Rudbeckia, Solidago, Symphoricarpos, Trifolium, Verbena, Veronica). dung, and mud (Heitzman 1964; Pyle 2002; James and Nunnallee 2011; Scott 2014).

Females lay eggs singly or in loose groups of 2-3 on host plant leaves, on either surface about midway up near the edge (Heitzman 1964; Scott 1986, 1992, 2006; James and Nunnallee 2011). Eggs hatch in about 9-10 days (depending on temperature), develop to L5 instar and pupae in about 42 days post egg-hatch, adults eclose (emerge from pupae) in about 15-16 days (Heitzman 1964; James and Nunnallee 2011). Larvae feed on host plant leaves, live in tubular nests of rolled or silk-tied leaves, feed nocturnally, overwinter (diapause) as L3 instar, pupate in silk-lined tube the following spring near the base of host plant (Heitzman 1964; Scott 1979, 1986, 1992; James and Nunnallee 2011). Males perch throughout the day 0.5-1.0 m above ground on grasses and other vegetation in gullies and swales, awaiting passing females (Scott 1975b, 1986; James and Nunnallee 2011).