Range:
This species ranges from southern Alberta and Saskatchewan and southwestern
Manitoba south through the Rockies and western Plains of the U.S. to central
New Mexico and Arizona, and west into Nevada and central California. In Idaho, it has been documented to occur in Owyhee, Lemhi,
and Custer counties.
Habitat:
It occurs in open, dry areas such as prairies, grasslands,
and sagebrush steppe.
Diet:
Caterpillar:
Caterpillars feed on the leaves of blue grama grass (Bouteloua gracilis).
Adult:
Butterflies feed rarely; the food of choice is flower nectar, primarily from
yellow flowers in the sunflower family (Asteraceae).
Ecology:
There is usually only one new generation of caterpillars each
year. Third and fourth instar
caterpillars may overwinter in a physiological state called diapause. In a small portion of its
range in California (Tuolumne County), the species is biennial. There, adults are only seen
in even-numbered years because the caterpillars overwinter twice, the first
winter as young caterpillars and the second after having molted several times. Pupation occurs in the spring. Adults
generally fly
from late May to early August. They hide in vegetation and exhibit an erratic
flight when flushed.
Reproduction:
Males perch to
wait for receptive females. Females lay white eggs singly on the host grass
and other plants.
Conservation:
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Global Rank: | G5
populations are widespread, abundant, and secure. |
Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm (Version 05Nov98).
Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies. Second Edition. Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.
Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.
Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.
Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.