It is found in western North America from California south to Baja California Norte and then west to southern Colorado and New Mexico.

[2] This species may also occur in Oregon and Washington, but more study is needed to verify this.

Adults are on wing from mid April to August in one generation per year.

They feed on the flower nectar of various plants, but mostly Eriogonum species.

The El Segundo blue (Euphilotes allyni) was originally thought to be a subspecies, but recent authorities consider it its own species.