Species Page: Milbert’s Tortoise Shell (Aglais milberti)

Milbert’s Tortoiseshell

Aglais milberti (Godart, 1819)

Family: Nymphalidae

Status: Occasional resident

NENHP Rank: S3, Tier 2

Range: This species is found throughout the southern half of Canada and Alaska and in the northern United States. In the western U. S. it extends southward at higher elevations into southern portions of California, Arizona and New Mexico. In Nebraska it has been found primarily in the panhandle although there are scattered records from eastern and southern counties as well.

Larval Hostplant(s): Stinging nettles (Urtica dioica).

Broods/Flight Times: Probably double brooded, with flights in early and late summer, the late summer adults overwintering and accounting for the early spring records. It is recorded in Nebraska from 13 April – 25 September.

Overwintering: As adults.

Habitat: Adults are most often found in the rugged country of western Nebraska where their hostplants can be found along streams and in moister portions of canyons. This butterfly has been observed in urban settings (Omaha, UN Campus-Lincoln) from time to time but not frequently enough to suspect they are residents there.

Avg. Wingspan: 1 5/8 – 2 1/2 inches

Found at: Gilbert-Baker SWMA, Wildcat Hills SRA, Agate Fossil Beds NM, Ash Hollow SHP

Similar Species: Hindwing might resemble some Anglewings (Polygonia sp.)