Shasta Blue
Plebejus shasta (W.H. Edwards, 1862)
Family: Lycaenidae
Subfamily: Polyommatinae
Identification: Upperside of male lilac blue with a wide dark border; female darker, may have orange band at outer margin of hindwing. Both sexes with dark cell bars on fore- and hindwings. Underside of both sexes gray with black postmedian spots; other spots are dark gray. Hindwing outer margin with iridescent green spots capped by a light band.
Wing Span: 7/8 - 1 1/8 inches (2.2 - 3 cm).
Life History: Males fly just above the ground to search for females. Eggs are laid singly on leaves of host plants; caterpillars feed on leaves and flowers. Where found above timberline, these butterflies require 2 years to mature, spending their first winter as eggs and the second winter as mature caterpillars.
Flight: One brood from June-August.
Caterpillar Hosts: Various Astragalus, Lupinus, and Trifolium species of the pea family (Fabaceae).
Adult Food: Flower nectar.
Habitat: Cushion-plant communities in forest openings, sagebrush hills, high plains, prairies, and alpine fell-fields.
Range: High elevations from Washington east to North Dakota and Nebraska; south to central California and Colorado.
Conservation: Not usually of conservation concern.
NCGR: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Management Needs: Not reported.
Comments: NULL
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Verified Sightings
Displaying 1 - 24 of 328 verified sightings
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/blue_shasta_plebejus_shasta_07-31-2024_10200_ft_saddlebags_south_side_trail_tuolumne_co_ca_-01.jpg?itok=dPooi7dH)
Observation date: Jul 31, 2024
Submitted by: ASchmierer
Region: Mono County, California, United States
Verified by: Ken Davenport
Verified date: Aug 02, 2024
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/p1390797.jpg?itok=nffrqaF2)
Observation date: Aug 29, 2023
Submitted by: Robert Gorman
Region: Mono County, California, United States
Verified by: Ken Davenport
Verified date: Sep 24, 2023
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/shasta_blue_img_7558.jpg?itok=bqr4kvEb)
Observation date: Jul 13, 2023
Submitted by: ncrosbyrd
Region: Summit County, Colorado, United States
Verified by: mikefisher
Verified date: Sep 10, 2023
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/127_15.jpg?itok=jFtA1jUt)
Observation date: Jul 10, 2018
Submitted by: Cheri Phillips
Region: Larimer County, Colorado, United States
Verified by: mikefisher
Verified date: May 29, 2023
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/large_512.jpg?itok=0RlMnijA)
Observation date: Jul 04, 2018
Submitted by: Robb Hannawacker
Region: Cache County, Utah, United States
Verified by: RaisingButterfl...
Verified date: Dec 15, 2022
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/shasta_blue_maki_diamond_peak.jpg?itok=pG9cfeUd)
Observation date: Aug 21, 2022
Submitted by: MAKI
Region: Eureka County, Nevada, United States
Verified by: Ken Davenport
Verified date: Oct 13, 2022
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/shasta_blue_2.jpg?itok=oycB5sQv)
Observation date: Sep 09, 2022
Submitted by: dchartier
Region: Summit County, Colorado, United States
Verified by: mikefisher
Verified date: Oct 02, 2022
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/plebejus_shasta_lycaenidae_bigmarshcr_6020_xing_11jul2021_2526_rdc.jpg?itok=KwowBeSC)
Observation date: Jul 11, 2021
Submitted by: smasta
Region: Klamath County, Oregon, United States
Verified by: Ken Davenport
Verified date: Dec 31, 2021
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/shasta_blue_1.jpg?itok=C-MzIv44)
Observation date: Jul 31, 2021
Submitted by: bjones7777
Region: Park County, Wyoming, United States
Verified by: J_Martineau
Verified date: Sep 07, 2021
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/p7200212.jpg?itok=qlm9PdUR)
Observation date: Jul 20, 2021
Submitted by: mstanek
Region: Mariposa County, California, United States
Verified by: Ken Davenport
Verified date: Jul 21, 2021
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/20140711_114043_3.jpg?itok=xx-fY6l1)
Observation date: Jul 11, 2014
Submitted by: chherrmann
Region: Clark County, Nevada, United States
Verified by: Ken Davenport
Verified date: Jun 14, 2021
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/shasta_blue.jpeg?itok=1NlQNQ1Q)
Observation date: Jul 25, 2020
Submitted by: papilio1
Region: Washoe County, Nevada, United States
Verified by: Ken Davenport
Verified date: Jul 29, 2020
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/dscn7806.jpg?itok=-dj3hpes)
Observation date: Jun 25, 2019
Submitted by: J_Martineau
Region: Natrona County, Wyoming, United States
Verified by: J_Martineau
Verified date: Dec 04, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/img_6903_4.jpg?itok=-bgsy0jM)
Observation date: Jul 28, 2019
Submitted by: A_baldini
Region: Larimer County, Colorado, United States
Verified by: mikefisher
Verified date: Oct 13, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/img_0806-bl8.jpg?itok=lGkK5RW_)
Observation date: Sep 08, 2019
Submitted by: sfbaywildlife
Region: California, United States
Verified by: Ken Davenport
Verified date: Sep 21, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/fullsizeoutput_8ea.jpeg?itok=WgrF6QDU)
Observation date: Aug 25, 2019
Submitted by: tirvine2020
Region: Teton County, Wyoming, United States
Verified by: J_Martineau
Verified date: Sep 04, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/shasta_blue_3250.jpg?itok=W7TZqcrM)
Observation date: Jul 14, 2019
Submitted by: tomoclark
Region: Modoc County, California, United States
Verified by: Ken Davenport
Verified date: Jul 20, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/blue_shasta_img_1270.jpg?itok=GhshnE0w)
Observation date: Jun 26, 2019
Submitted by: ncrosbyrd
Region: Deschutes County, Oregon, United States
Verified by: Ken Davenport
Verified date: Jul 14, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/sb_3.png?itok=7QnDa-1I)
Observation date: Aug 23, 2008
Submitted by: hydapse
Region: Park County, Wyoming, United States
Verified by: J_Martineau
Verified date: Feb 07, 2019
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/filefield_paths/p1270301.jpg?itok=eFJot5xT)
Observation date: Aug 08, 2018
Submitted by: Robert Gorman
Region: Mono County, California, United States
Verified by: Ken Davenport
Verified date: Aug 20, 2018
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/filefield_paths/shastablue071518greatbasinnationalpark.jpg?itok=EfPsIojN)
Observation date: Jul 15, 2018
Submitted by: Lisahug
Region: White Pine County, Nevada, United States
Verified by: Ken Davenport
Verified date: Aug 03, 2018
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/p1690959.jpg?itok=X4poJ6YZ)
Observation date: Jul 12, 2018
Submitted by: Robert Gorman
Region: Sierra County, California, United States
Verified by: Ken Davenport
Verified date: Jul 19, 2018
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/p1230566.jpg?itok=SEiub-l5)
Observation date: Jul 14, 2018
Submitted by: Robert Gorman
Region: Mono County, California, United States
Verified by: Ken Davenport
Verified date: Jul 18, 2018
![](https://www.butterfliesandmoths.org/sites/default/files/styles/bamona_scale_and_crop_640px_by_640px/public/bamona_images/20160806_120256_-_copy.jpg?itok=ECih3VhF)
Observation date: Aug 06, 2016
Submitted by: coreyk
Region: Mono County, California, United States
Verified by: Ken Davenport
Verified date: Aug 12, 2016
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