Silvery Blue
Glaucopsyche lygdamus (Doubleday, 1841)
Family: Lycaenidae
Subfamily: Polyommatinae
Identification: Upperside of male iridescent silvery blue with narrow dark borders; female darker blue with wide borders. Both sexes have white fringe. Underside gray-brown; both wings with row of white-ringed, round black spots. Subspecies xerces (Boisduval) and pseudoxerces Emmel and Emmel have large white spots with or without black centers.
Wing Span: 7/8 - 1 1/4 inches (2.2 - 3.2 cm).
Life History: Males patrol near the host plants for females. Eggs are laid singly on flower buds and young leaves of the host plants. Caterpillars feed on flowers, seedpods, and young leaves and are tended by ants. Chrysalids hibernate.
Flight: One flight from March-June at low elevations, June-August at high elevations.
Caterpillar Hosts: Astragalus, Lotus, Lupinus, Melilotus, Oxytropis, Lathyrus, Vicia, and other species in the pea family.
Adult Food: Nectar from flowers including Asteraceae.
Habitat: A variety of locations including open woods, coastal dunes, prairies, meadows, road edges, rocky moist woods, and brushy fields.
Range: Central Alaska south to southern California, Baja California, Arizona, New Mexico, and western Kansas. Along northern United States east to Nova Scotia and south to Georgia.
Conservation: Subspecies palosverdesensis is thought to be extinct. Its historic range and its hostplant Astragalus leucopsis in the Palos Verdes Hills in Los Angeles County, California is largely extirpated, but an additional population was discovered in nearby San Pedro. This subspecies has The Nature Conservancy rank of T1 - Critically imperiled globally because of extreme rarity (5 or fewer occurrences, or very few remaining individuals), or because of some factor of its biology making it especially vulnerable to extinction. (Critically endangered throughout its range). Subspecies xerces is TX - Presumed extinct. Subspecies pseudoxerces is rank T2.
NCGR:
Management Needs: Conserve all remaining habitat for the Palos Verdes Blue. Investigate status and conservation needs of subspecies pseudoxerces.
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Verified Sightings
Displaying 1 - 24 of 2823 verified sightings

Observation date: Jun 28, 2024
Submitted by: Ratty
Region: Saskatchewan, Canada
Verified by: jmgesell
Verified date: Jul 07, 2025

Observation date: Jul 02, 2025
Submitted by: regina rochefort
Region: Skagit County, Washington, United States
Verified by: davidwdroppers
Verified date: Jul 06, 2025

Observation date: Jul 05, 2025
Submitted by: JChris173
Region: Alberta, Canada
Verified by: James Steen
Verified date: Jul 06, 2025

Observation date: Jul 08, 2024
Submitted by: Geoff Urwin
Region: Saskatchewan, Canada
Verified by: jmgesell
Verified date: Jul 05, 2025

Observation date: Jul 03, 2025
Submitted by: Black Spruce Girl
Region: Alberta, Canada
Verified by: James Steen
Verified date: Jul 03, 2025

Observation date: Jul 01, 2025
Submitted by: John Gibbons
Region: Newfoundland and Labrador, Canada
Verified by: jwileyrains
Verified date: Jul 02, 2025

Observation date: Jun 25, 2025
Submitted by: John Terpstra
Region: Ontario, Canada
Verified by: jmgesell
Verified date: Jun 27, 2025

Observation date: Jun 25, 2025
Submitted by: John Terpstra
Region: Ontario, Canada
Verified by: jmgesell
Verified date: Jun 27, 2025

Observation date: Jun 13, 2025
Submitted by: barthsm
Region: Wheatland County, Montana, United States
Verified by: J_Martineau
Verified date: Jun 23, 2025

Observation date: Jun 16, 2025
Submitted by: Kate McKay
Region: Alberta, Canada
Verified by: James Steen
Verified date: Jun 20, 2025

Observation date: Jun 16, 2025
Submitted by: Sometimes
Region: Ontario, Canada
Verified by: jmgesell
Verified date: Jun 16, 2025

Observation date: Jun 23, 2006
Submitted by: Tom Dudones
Region: Franklin County, New York, United States
Verified by: jmgesell
Verified date: Jun 12, 2025

Observation date: Jun 11, 2025
Submitted by: Dogoszhi
Region: Sandoval County, New Mexico, United States
Verified by: stevecary
Verified date: Jun 12, 2025

Observation date: Jun 11, 2025
Submitted by: Tom Dudones
Region: Essex County, New York, United States
Verified by: jmgesell
Verified date: Jun 12, 2025

Observation date: Jun 11, 2025
Submitted by: Tom Dudones
Region: Essex County, New York, United States
Verified by: jmgesell
Verified date: Jun 12, 2025

Observation date: Jun 11, 2025
Submitted by: Tom Dudones
Region: Essex County, New York, United States
Verified by: jmgesell
Verified date: Jun 11, 2025

Observation date: Jun 09, 2025
Submitted by: John Terpstra
Region: Ontario, Canada
Verified by: jmgesell
Verified date: Jun 11, 2025

Observation date: Jun 01, 2025
Submitted by: ezeemonee
Region: Jefferson County, Colorado, United States
Verified by: mikefisher
Verified date: Jun 08, 2025

Observation date: Jun 01, 2025
Submitted by: Marta Reece
Region: Lincoln County, New Mexico, United States
Verified by: stevecary
Verified date: Jun 05, 2025

Observation date: May 21, 2025
Submitted by: Fladder
Region: Tuolumne County, California, United States
Verified by: Ken Davenport
Verified date: Jun 03, 2025

Observation date: May 25, 2025
Submitted by: ezeemonee
Region: Santa Barbara County, California, United States
Verified by: Ken Davenport
Verified date: May 29, 2025

Observation date: May 21, 2025
Submitted by: Dogoszhi
Region: Sandoval County, New Mexico, United States
Verified by: stevecary
Verified date: May 22, 2025

Observation date: Apr 28, 2025
Submitted by: mstanek
Region: Ventura County, California, United States
Verified by: Ken Davenport
Verified date: May 01, 2025

Observation date: Apr 22, 2025
Submitted by: MAKI
Region: Santa Barbara County, California, United States
Verified by: Ken Davenport
Verified date: Apr 27, 2025
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