Appearance: Short projections on both wings, borders irregular. Above, an intense rusty brown with broad yellow borders on outer margins, and a row of iridescent blue spots at the inner edge of the border; below, a blackish brown color with a paler border. The lower surface provides excellent camouflage when pressed against the trunk of a tree.
Size: Large; 2 1/4 to 4 inches
Habitat: A wide variety of habitats including woods, fields, meadows, parks, gardens, riparian areas, suburbs and cities
Season: Normally March to mid-September, but any month of the year is possible. (An early December sighting reported in Boulder, 2010 and possible during a warm snap in January and/or February)
Larval Foodplant: Depending on altitude, could include aspen, birch, willow, or at lower elevations cottonwood, elm, or hackberry
Did You Know…
Maybe our longest living butterfly (10-12 months) (Opler, 1999) as they overwinter as adults, emerge in the spring and possibly aestivate during the heat of summer to appear one last time in the fall. It is sometimes possible to see fresh, newly emerged, adults flying in the fall with last year’s tattered and soon to expire adults that overwintered the previous year.
Species Gallery (click to enlarge)