Description: Wings delicate, 19 - 28 mm (0.75 - 1.10 in.) wingspan. Males blue in color with checkered wing fringes; females typically brown, may be spotted. Adults found in the vicinity of the host plant, sulphur flower buckwheat (Eriogonum umbellatum), which is also the larval host plant. Flight season from June to late July, males appearing one month before females; this variety appears to have two flights per year coinciding with flowering of its host plant.
Diet: Adult food consists of nectar of sulphur flower buckwheat; larvae (caterpillars) eat flowers and fruit of the same host plant. Male dark blue butterfly may be found near springs to obtain dissolved nutrients from mud.
Habitat: Stream banks, springs, and seeps, primarily in mixed conifer and pinyon-juniper communities; also uses sagebrush and wet areas near high elevation springs. Elevations: 1,500 - 2,500 m (4,920 - 8,200 ft).
Range: Endemic to the Spring Mountains, Clark County, Nevada. Known only from few areas, including Willow Creek and Cold Creek, Kyle Canyon, Carpenter Canyon, Mount Stirling, Coal Springs, and Lovell Canyon.
Comments: The MSHCP lists the old nomenclature, Euphilotes enoptes purpurea. Also, the common name more often used is Spring Mountains Dark Blue.