Icaricia shasta (W. H. Edwards, 1862)
Status: Uncommon resident
NENHP Rank: S2 Tier 2
Range: This butterfly is found from southern Alberta south through Colorado and west into central California and Oregon. In Nebraska it has been found in the panhandle as far east as the bluffs south of the Platte River along Highway 27 In Garden County.
Larval Hostplant(s): Astragalus kentrophyta , and possibly Tufted Milkvetch (A. spatulatus).
Broods/Flight Times: There is one early summer flight. In Nebraska it has been found from May 24 – June 22.
Overwintering: This species has been reported to be biennial (requiring two years to complete its life cycle) in some higher elevation portions of its range, overwintering the first year as an egg and the second as a nearly fully-grown caterpillar. The overwintering status for this species has not been confirmed in Nebraska where its lowest altitude populations occur.
Habitat: Rocky outcroppings in the Pine Ridge and “badlands” type hilltops. Their typical habitat is ledges and hilltops of rocky or poor soil nearly devoid of all vegetation with the exception of a few hardy plants of which their host plants are included. Adults fly within inches of the ground in the vicinity of its host plants.
Avg. Wingspan: 7/8 – 1 1/8 inches
Similar Species: Reakirt’s and Marine Blues