Mylitta crescent (Phyciodes mylitta [W. H. Edwards])
Wing span: 1 1/8 - 1 1/2 inches (3 - 3.8 cm).
Identification: Upperside is bright reddish orange with narrow dark markings. Lacks the prominent black inner marginal spot of Phyciodes pallidus. Underside is yellow-orange with somewhat blurry rusty orange markings.
Life history: Males perch or patrol all day near host plants for females. Eggs are deposited on underside of host plant leaves; caterpillars eat leaves. Young caterpillars may live in a small silken nest; partially-grown caterpillars hibernate.
Flight: Two broods in the north from April-September, several in the south from February-November.
Caterpillar hosts: Native thistles (Cirsium), milk thistle (Silybum marianum), and European thistles (Carduus).
Adult food: Flower nectar.
Habitat: From sea level to 8000 feet in mountains, fields, meadows, roads, vacant lots, parks, and fencerows.
Range: Southern British Columbia southeast through the Rocky Mountain region to Mexico; south to Washington, Oregon, and California.
Conservation: Not usually required.
The Nature Conservancy Global Rank: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Management needs: None reported.
References:
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