Pontia protodice
Checkered White
Family:Pieridae
Family Description:
Alternate Common Name: Common White.
Note: Some sources refer to this species with the older genus name Pieris.
Description:
Caterpillar: The caterpillar is bluish green to bluish gray, striped lengthwise with yellow on the back and sides, and dotted with black. The head is yellow; the body is covered with downy hair.
Adult: The butterfly is medium-sized, with a wingspan of 1 ¼ to 2 ½ inches. It varies considerably in the intensity of its markings, both between the sexes and seasonally. Generally, the upperside is white marked with black. The forewing has two large black patches, and a black border marked with white triangles. The hindwing is also bordered with black; the border is interrupted with white triangle- or diamond-shaped spots. The veins may be outlined in gray. The underside varies from nearly pure white with a few brownish spots, to white spotted with brown on the forewing and striped with brown or grayish green on the hindwing. Variations: Females may have brown instead of black, and the markings may appear more cloudy. Also, males may be entirely white except for a black spot on the forewing, if they developed during the summer months.

Range:
This widespread species ranges from south central Canada, through most of the U.S. to northern Mexico. It is absent from the state of Washington and northern New England. It is a yearlong resident in the southern part of its range. It occurs through much of Idaho.

Habitat:
 It occurs in a variety of common habitats, including fields, vacant lots, pastures, and weedy and disturbed areas.

Diet:

Caterpillar: Caterpillars feed on most parts of native and introduced members of the mustard family (Brassicaceae) and the caper family (Capparidaceae).
Adult: Butterflies drink flower nectar.

Ecology:
There are generally three generations of caterpillars each year through most of its range. There may be four in parts of the south, and in certain regions there may be continuous generations. Pupae can overwinter in a physiological state called diapause. Adults generally fly from February to November, but may fly all year long in the southernmost part of its range.

Reproduction:
 Males actively patrol in search of receptive females, although females have been reported to seek out males as well. Females lay yellow eggs singly on the leaves and flowers of host plants.

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

G4; population levels are secure, but may be of concern in the future.

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.