Pieris virginiensis

West Virginia white
On wild mustard
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Lepidoptera
Family:	Pieridae
Tribe:	Pierini
Genus:	Pieris
Species:	P. virginiensis
Binomial name
Pieris virginiensis Edwards, 1870

Pieris virginiensis, the West Virginia white, is a butterfly found in North America in the Great Lakes states, along the Appalachians from New England to Alabama, and in southern Ontario. They are typically found in moist deciduous forests. Forestry, development, and a highly-invasive species that it confuses with its host plant are causing this species to decline.

Along with the butterfly Pieris oleracea, it is threatened by the invasive weed garlic mustard, Alliaria petiolata. The butterflies, having not evolved to be familiar with the plant, confuse it with their host plants. The offspring laid on garlic mustard do not survive.

It has translucent whitish wings of length 4.5–5.5 cm; the hindwing underside has brownish or pale gray scaling along the veins.

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Wikipedia