Glaucopsyche lygdamus
Glaucopsyche lygdamus, the silvery blue, is a small butterfly native to North America.
Description
Its upperside is a light blue in males and a dull grayish blue in females. The underside is gray with a single row of round spots of differing sizes depending upon the region.Distribution and habitat
G. lygdamus is found over much of the western United States and most of Canada extending north excepting most of Nunavut and the high Arctic islands. Wingspan is from 18 to 28 mm. It occurs in a variety of habitats including alpine meadows, shale barrens, dunes, and wooded areas. It feeds on Lupinus plants.Taxonomy
The extinct Xerces blue was once thought to be a subspecies of the silvery blue.Subspecies
Listed alphabetically:G. l. afra - Afra blueG. l. arizonensis McDunnough, 1934 - Arizona silvery blueG. l. australis - southern blueG. l. columbia - Columbia blue or Skinner's blueG. l. couperi Grote, 1873 - Couper's silvery blueG. l. deserticola - Mojave silvery blueG. l. incognitus Tilden, 1974 - Behr's silvery blueG. l. jacki Stallings & Turner, 1947 - Jack's blueG. l. lygdamus - silvery blueG. l. mildredae F. Chermock, 1944 - Mildred's silvery blueG. l. minipunctum - mini-spotted silvery blueG. l. nittanyensis - Appalachian silvery blueG. l. oro Scudder, 1876 - oro blueG. l. palosverdesensis - Palos Verdes blueG. l. pseudoxerces - false Xerces blueG. l. sabulosa - sand dune silvery blueVisually similar species
- Eastern tailed-blue has small 'tails' on hindwings
- Western tailed-blue has small 'tails' on hindwings
- Arrowhead blue
- Greenish blue has two rows of small black spots on the underside of both wings
- Boisduval's blue has two rows of small black spots on the underside of both wings