Although this species has been divided into several subspecies, some with very small ranges, all our populations are considered subspecies windi. One of our earliest-flying species - generally only 2-3 weeks after snowmelt - and therefore very easy to miss. Although it does occur in the Coast Range near Lake Berryessa, it is unrecorded at Gates Canyon. In the Sierra it occurs at Washington, Lang Crossing, and Donner. At lower elevations (5000' and below) usually found on cool, damp north-facing cliffs with mats of Sedum, the host plant.