Butterflies and Moths of North America

collecting and sharing data about Lepidoptera

Russet Skipperling
Piruna pirus (W.H. Edwards, 1878)


Family: Hesperiidae
Subfamily: Hesperiinae
Identification: Upperside is dark brown; underside is red-brown. Forewing above and below has tiny transparent white spots; hindwing has no markings above or below.
Wing Span: 1 - 1 1/8 inches (2.5 - 2.9 cm).
Life History: Adults rest with their wings closed, but bask with hindwings open wide and forewings open to about 45 degrees. To find receptive females, males patrol above low plants in river courses, streams, and moist ravines. Caterpillars live and feed within nests of webbed leaves. Fully-grown caterpillars hibernate.
Flight: One brood from June-July.
Caterpillar Hosts: Probably grasses such as bluegrass (Poa).
Adult Food: Flower nectar.
Habitat: Moist valley bottoms, forest openings, meadows.
Range: Southeastern Idaho, southern Wyoming, Utah, Colorado, Arizona, and New Mexico.
Conservation: Not usually required.
NCGR: G4 - Apparently secure globally, though it might be quite rare in parts of its range, especially at the periphery.
Management Needs: None reported.
Comments: NULL