Erynnis lacustra

Sleepy Duskywing

For a long time, I thought of the sleepy duskywing as rare, since I had seen it so rarely at Cactus Spring Trail (and nowhere else), a place I've gone to regularly for years. But to the west at Keen Camp Summit near Idyllwild, I found several in late April across several visits in 2021, and I've since learned it can be locally common. Identification is easy: they have irregular dark striping across the forewings but lack the light hyaline patches of the other duskywings. They fly in April and May in a single brood, and mature caterpillars overwinter in a shelter made of oak leaves. In the spring, they pupate and again emerge in April.