This is a "complex" of several biological entities which may be "good species;" we have much to learn. All the populations along our transect are in the Sierra Nevada and are associated with Sulphur Flower, Eriogonum umbellatum - which itself may be more than one species! The butterflies are always single-brooded and emerge when their hosts (which are their principal, if not sole nectar sources) are in bloom, generally in late spring-early summer. Males are avid puddlers.

Like the Square-Spotted Blue, this is a "complex" of entities in evolutionary ferment. However, along our transect there is no such complexity. All of our populations, from the Sierra foothills over the crest, feed on the Eriogonum nudum group of Wild Buckwheats and have very similar life histories - one brood in late spring-early summer, matching the blooming time of the host. Adults rarely stray more than a few feet from the host, although males do puddle. They mate on the host and roost on it for the night.