Species Page: Northwestern Fritillary (Argynnis hesperis)

Northwestern Fritillary

Argynnis hesperis (W. H. Edwards, 1864)

Family: Nymphalidae

Status: Rare resident, possibly extirpated

NENHP Rank: Not listed

Range: The Northwestern Fritillay is found through much of the northern United States and central and southern Canada from the Atlantic to the Pacific, and in montane areas in the western United States south into much of Arizona and New Mexico.

Larval Hostplant(s): Various violets (Viola species).

Broods/Flight Times: There is one flight. The few records from Nebraska are from July 10-16.

Overwintering: As unfed caterpillar.

Habitat: Pine Ridge canyons.

Avg. Wingspan: 2 – 2 3/4 inches

Found at:

Similar Species: Aphrodite Fritillary

Notes: Merritt Cary and his associates collected three or four “Atlantis” Fritillaries in Pine Ridge canyons in July of 1901 (these specimens are in the collections of the University of Nebraska at Lincoln). In 1998 it was determined that hesperis, formerly a subspecies of atlantis, was a separate species, and that Nebraska’s specimens were hesperis. Neither “species” has been found in Nebraska since that time.