Fringes are brown. Upperside of male forewing is dark brown with little contrast and no white overscaling. Upperside of female forewing is light brown with a contrasting pattern and large transparent spots. Underside of hindwing is usually without 2 spots below the apex.
Caterpillars feed on young leaves and rest in leaf nests.
Caterpillars of the last brood hibernate. Horace's Duskywing visits flower up to about 4.5 feet tall including dogbane, buttonbush, sneezeweed, goldenrod, peppermint, boneset, and winter cress. G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery. Opler, P. A. and G. O. Krizek. Butterflies east of the Great Plains.