North American Butterflies and Moths List

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Butterflies of North America

Sonoran Blue (Philotes sonorensis)
JPG -- species photo

Sonoran Blue (Philotes sonorensis [Felder & Felder])

Wing span: 7/8 - 1 inch (2.2 - 2.5 cm).

Identification: Our only blue with red spots on forewing. Upperside silvery blue; forewing of both sexes with red spots at outer margin; hindwing of female also with red spots.

Life history: Males patrol with a weak flight near the host plant for females. Eggs are laid singly on the leaves, and caterpillars bore into them to feed. Chrysalids hibernate under stones.

Flight: One flight from February-March.

Caterpillar hosts: Stonecrop (Dudleya species) in the Crassulaceae family.

Adult food: Not reported.

Habitat: Rocky washes, outcrops, and cliffs in desert.

Range: Very local. Placer County, California west to Santa Clara County; along coast through southern California to Baja California.

Conservation: Subspecies extinctis occurred in the upper San Gabriel river wash in southern California, but has been extinct since 1968 when its habitat was destroyed.

The Nature Conservancy Global Rank: G3 - Very rare or local throughout its range or found locally in a restricted range (21 to 100 occurrences). (Threatened throughout its range).

Management needs: Protect colonies from habitat modification.


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

Sonoran Blue (Philotes sonorensis)
distribution map
map legend

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