Vanessa cardui
Painted Lady

Family:Nymphalidae
Family Description:
Alternate Common Names: Thistle Butterfly, Cosmopolite, Cosmopolitan.
Note: This and the other Painted Lady butterflies are sometimes grouped in their own genus or subgenus, Cynthia.

Description:
Caterpillar: The caterpillar varies in its appearance. It can be grayish brown ringed with yellow, greenish yellow, or black. It is always striped lengthwise with yellow along each side and covered with branching spines. It reaches a maximum, full-grown length of 1 1/4 inches.
Adult: This is a medium-sized butterfly, with a wingspan of 2 to 2 7/8 inches. The tip of the forewing is slightly elongated and rounded. The upperside is largely pinkish orange to brownish orange, and may be darker at the bases of the wings. The forewing is marked with uneven patches of black, and is solid black, spotted with white, at the tip. The hindwing is marked with a curved row of blue spots, followed by a row of black triangles, and is edged with an orange and black border. Underneath, the forewing is reddish pink towards the base and mottled brown and white towards the tip. The underside of the hindwing is entirely mottled with brown and white, and is marked with four to five blue or black eyespots.

Range:
This butterfly occurs on all of the continents except Australia and Antarctica, and is considered by some to be the world’s most widely distributed butterfly. In North America, it ranges from northern Mexico to the subarctic of Canada for part of the year. It can be found throughout most of Idaho.

Habitat:
It utilizes almost every habitat, particularly open or disturbed areas.

Diet:

Caterpillar: Caterpillars feed on the leaves of a wide variety of plants from over ten families including the sunflower family (Asteraceae), the goosefoot family (Chenopodiaceae), the mallow family (Malvaceae), and the pea family (Fabaceae); thistles (Cirsium spp.) seem to be preferred.
Adult: Butterflies drink flower nectar, most commonly from tall flowers in the sunflower family (Asteraceae). They may also use aphid honeydew for food.

Ecology:
Each caterpillar forms a nest of silk on the topside of host plant leaves. The number of generations of caterpillars each year varies regionally, with most areas having one to three, and with many occurring all year long in the south. Adults overwinter in a physiological state called diapause in the south and where winters are mild; pupae may overwinter, as well. Annually, butterflies migrate north in the spring, sometimes in large numbers; they do not usually exhibit a similar return trip en masse south in the fall. They generally fly from early spring to November.

Reproduction:
 Males both perch to wait for and actively patrol in search of receptive females. Perching in the west typically occurs in shrubs located on hilltops, while in the east it occurs on open, bare ground. Females lay green eggs singly on the uppersides of the leaves of host plants.

Conservation:
Idaho Status: Unprotected nongame species.
Global Rank:

G5; populations are widespread, abundant, and secure.

References:
 Ferris, C. D. and F. M. Brown. (eds.) 1981. Butterflies of the Rocky Mountain States. Univ. of Oklahoma Press, Norman, Oklahoma, USA, 442 pp.

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.