Designation of Critical Habitat for Mount Charleston Blue Butterfly (Icaricia (Plebejus) shasta charlestonensis)

We, the U.S. Fish and Wildlife Service (Service), designate critical habitat for the Mount Charleston blue butterfly (Icaricia (Plebejus) shasta charlestonensis) under the Endangered Species Act of 1973, as amended (Act). In total, approximately 5,214 acres (2,110 hectares) in the Spring Mountains of Clark County, Nevada, fall within the boundaries of the critical habitat designation. The effect of this rule is to extend the Act's protections to the butterfly's critical habitat.