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BC Conservation Data Centre: Species Summary


Icaricia icarioides blackmorei
Boisduval's Blue, blackmorei subspecies

 
Scientific Name: Icaricia icarioides blackmorei (Barnes and McDunnough, 1919)
Scientific Name Synonyms: Icaricia icarioides blackmorei
Plebejus icarioides blackmorei
English Name: Boisduval's Blue, blackmorei subspecies
 
Classification / Taxonomy
Scientific Name - Concept Reference: Pelham, J. P. 2008. A catalogue of the butterflies of the United States and Canada with a complete bibliography of the descriptive and systematic literature. The Journal of Research on the Lepidoptera. Volume 40. 658 pp. Revised 14 February, 2012.
Classification Level: Subspecies
Species Group: Invertebrate Animal
Species Code: LE-PLEICA-BL
Kingdom Phylum Class Order Family
Animalia Arthropoda Insecta Lepidoptera Lycaenidae
   
Conservation Status / Legal Designation
Global Status: G5T3 (Jun 2006)
Provincial Status: S3 (Mar 2021)
BC List: Blue
Provincial FRPA list:   
Provincial Wildlife Act:
COSEWIC Status:
SARA Schedule:
General Status Canada:
   
Ecology & Life History
General Description:
Subspecies Comments: Over one dozen subspecies have been described for Plebejus icarioides, although only three subspecies are known to occur in British Columbia and Canada: P.i.blackmorei; P.i.montis and P.i. pembina.
Identification Comments: The taxonomy of this species is poor and should likely be revised.
Provincial Reproduction Comments: Eggs are laid singly (Layberry et al. 1998) throughout the adult flight period.
Provincial Ecology Comments: The nominate species is known to have associations with ants (Downey 1962), although no specific studies have been completed for this subspecies.
Migration Characteristics:
(Global / Provincial)		 
    Nonmigrant:
    Local Migrant:
    Distant Migrant:
    Within Borders Migrant: 		N / Y
N / N
N / N
na / N
Provincial Mobility & Migration Comments: Blue butterflies are not known to be good flyers, and tend to remain close to the ground. Boisduval's Blue is not known to have extensive flight capabilities, although specific studies have not been completed (Guppy and Shepard 2001).
Habitats:
(Type / Subtype / Dependence) 		Grassland/Shrub / Grassland / Facultative - frequent use
Grassland/Shrub / Meadow / Obligate
Provincial Habitat Comments: Historic records for Boisduval's Blue, blackmorei subspecies occur in low elevation Garry oak and associated grassland environments (CDC 2006; Guppy 2006). Current records for the species show it rarely occurs in these environments, perhaps due to invasive species encroachment that has competed with the food plants, native lupines (Lupinis spp.). The species has also been recorded in higher elevation areas, including sub-alpine and alpine meadows where native lupines occur (Guppy 2003).
Food Habits:
Global Food Habits Comments:
Provincial Food Habits Comments: Boisduval's Blue, blackmorei subspecies is known to use native lupines (Lupinis spp.) as the larval food plant (Layberry et al. 1998).
Global Phenology:
Provincial Phenology:
(1st half of month/
2nd half of month)		 May: / Active
June: / Active
July: / Active
Aug: / Active
Provincial Phenology Comments: Adult flight period is from mid May to early September (Guppy and Shepard 2001; Layberry et al. 1998). Populations in higher elevations have a shorter flight period. The nominate subspecies is known to overwinter as a larvae, and pupate sometime in the early spring with pupation taking three weeks before adult emergence. The specific life cycle of subspecies blackmorei is unknown, but likely similar to that of the nominate subspecies.
Colonial Breeder: N
Length(cm)/width(cm)/Weight(g): / /
Elevation (m) (min / max): Global: 
Provincial: 
   
 
Distribution
Endemic: N
Global Range Comment: Known from the east coast of Vancouver Island, in subalpine and alpine habitat, south into the Olympic Mountains, and on low elevation grasslands around southern Puget Sound.
 
Authors / Contributors
Global Information Author:
Last Updated: May 15, 2001
Provincial Information Author: Heron, J.
Last Updated: Feb 11, 2008
   
References and Related Literature
Baron, N., and F. Backhouse. 1999. Rare Butterflies of Southeastern Vancouver Island and the Gulf Islands. B.C. Minist. Environ., Lands and Parks, Wildl. Branch. 6pp.
Conservation Data Centre. 2006. CDC butterfly records database containing records from multiple observers.
Downey, J.C. 1962. Variation in Plebejus icarioides (Lepidoptera, Lycaenidae) II. Parasites of the immature stages. Ann. Ewnt. Soc. Amer. 55(4): 367-73
Guppy, C. 2006. Guppy's Lepidoptera observation database.
Guppy, C.S. 2003. Island Blue (Plebejus saepiolus insulanus), inventory of the mountains of southern Vancouver Island 2003. Report prepared for the Minist. Water, Land and Air Protection, Surrey, BC. 14pp + app.
Guppy, C.S., and J.H. Shepard. 2001. Butterflies of British Columbia. UBC Press in collaboration with Royal B.C. Mus. 414pp.
Layberry, R. A., P. W. Hall, and J. D. LaFontaine. 1998. The butterflies of Canada. University of Toronto Press. 280pp. + color plates.
 

Please visit the website Conservation Status Ranks for definitions of the data fields used in this summary report.

Suggested Citation:

B.C. Conservation Data Centre. 2001. Species Summary: Icaricia icarioides blackmorei. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Jun 10, 2026).