Northern Marble (Euchloe creusa [Doubleday])
Wing span: 1 3/8 - 1 5/8 inches (3.5 - 4.2 cm).
Identification: Pale markings at tip of upperside of front wing; cell bar narrow. Fore- and hindwing bases dark on the uppersides.
Underside of hindwing with considerable "fractured" dark marbling.
Life history: Females lay single eggs on host plant flower buds; caterpillars eat flowers and fruits. Chrysalids hibernate.
Flight: One flight from May-July.
Caterpillar hosts: Plants of the mustard (Brassicaceae) family.
Adult food: Flower nectar. Specific plants not reported.
Habitat: Mountains, rocky outcrops, trails, roadsides.
Range: Alaska south and east to British Columbia, Alberta, and Saskatchewan. Northern Montana in Glacier National Park.
Conservation: Widespread in Alaska, but very restricted in lower 48 states.
Management needs: Study habitat requirements and manage accordingly.
The Nature Conservancy Global Rank: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Opler, P. A. 1968. Studies on nearctic Euchloe. Part 5. Distribution. Journal of Research on the Lepidoptera 7(2): 65-86. Opler, P. A. 1969 (1970). Studies on nearctic Euchloe. Part 6. Systematic of adults. Journal of Research on the Lepidoptera 8(4): 153-168. Opler, P. A. 1974. Studies on nearctic Euchloe. Part 7. Comparative life histories, hosts, and the morphology of immature stages. Journal of Research on the Lepidoptera 13(1): 1-20. Scott, J. A. 1986. The butterflies of North America. Stanford University Press, Stanford, Calif. 583 pages, 64 color plates. Tilden, J. W. 1986. A field guide to western butterflies. Houghton-Mifflin Co., Boston, Mass. 370 pages, 23 color plates.
Author: Jane M. Struttmann