Lustrous copper butterflies (Lycaena cupreus) fly in the mountains of Washington, central and southeastern Oregon, the Sierra Nevada of California and across the Rocky Mountains. They can be found in mountain meadows, sagebrush flats, glacial cirques, rocky treeless areas and along roadsides.
There are three subspecies of lustrous coppers. Their upper sides are coppery red with small black spots, a black border and a white fringe. In females the spots are larger. On the underside, the forewing has an overall copper tinge and a black submarginal line. The rear wing is more greyish with a red submarginal line. Lustrous copper caterpillars are light green with a red lateral stripe and light red bands.
Lustrous copper females lay white (turning greyish with age) eggs singly on or near the leaves of the host plant. The half-grown caterpillar hibernates over the winter and pupates in the early spring. The larvae (caterpillars) eat members of the knotweed family, particularly sorrels. Adult lustrous coppers drink flower nectar, particularly the nectar of composites such as asters, pussy paws and dandelions.
This lustrous copper was photographed in May in the meadow upstream from the Lower Campground at Ash Creek (Modoc County CA).