Caterpillar food: originally native shrub legumes e.g. Wild Indigo (Baptisia spp.) and Canadian Milkvetch (Astragalus canadensis), but has now adapted to eating Crown Vetch (Coronilla varia) – an invasive exotic that is planted on roadsides

Wild Indigo Duskywings are impossible to visually tell apart from Columbine Duskywings (Erynnis lucilius).  Where both species are present, the only way to tell is by watching which plants they lay their eggs on.

This one was laying eggs on Astragalus canadensis – July 10, 2007

Top view of wings

I found several eggs, and raised them on Astragalus canadensis.

The caterpillars curled leaves to make a nest, and held them together with silk.

None of my larvae made it to adulthood.