E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Callophrys mossii Scudder, 1872
Elfins; Moss' Elfin
Family: Lycaenidae (Gossamer Wings)
Species account authors: Crispin Guppy and Jon Shepard.
Extracted from Butterflies of British Columbia
The Families of Lepidoptera of BC
Introduction to the Butterflies of BC

Photo of species

© Jeremy Gatten  Email the photographer   (Photo ID #6091)

E-Fauna BC Static Map
Distribution of Callophrys mossii in British Columbia
Details about map content are available here.

Species Information


For Moss' Elfin the ventral hindwing has a dark brown basal half and a grey postmedian area. The grey area is more contrasting for interior populations and obscure for Vancouver Island populations.

Immature Stages

Hardy (1957) described the entire life history. The egg is a pale pastel green, and is 0.75 mm x 0.33 mm in size. The raised edges of the sculptured surface are covered with hyaline margins, giving the egg a hoary appearance. Mature fourth instar larvae are 16-17 mm long. The body is greenish yellow. Some individuals have white-edged dorsal stripes and/or a white spiracular fold. The pupa is 11 mm x 17 mm in size. It is pale yellow at first but soon changes to dark chocolate brown with a pale dorsal line flanked by a double row of small fuscous dots on each side. Spiracles are white.


Vancouver Island populations are the nominate subspecies, I. m. mossii (Hy. Edwards, 1881) (TL: Esquimalt, BC). Interior populations are the Rocky Mountain subspecies, I. m. schryveri Cross, 1937 (TL: Chimney Gulch, CO).

Genus Description

The name Incisalia is of unknown derivation. The common name "elfins" refers to their small size and flight habits that make them seem to magically appear and disappear. It was first used for the genus by Scudder (1875).

Species of the genus Incisalia lack tails on the hindwing and green colouring on the ventral hindwings. The tips of the valves are "capped," meaning that they have a terminal thickening not found in the genera Callophrys, Mitoura, or Loranthomitoura. The cornuti are neither slender nor spatulate. This is a Nearctic genus, with nine species. Six species occur in BC.


Moss' Elfin flies from mid-April to late May. Early emergence depends on a warm, early spring. Eggs are usually laid at the base of the flower of the larval foodplant, Sedum spathulifolium (Hardy 1957). S. lanceolatum is probably used in the interior. Eggs hatch within days and the first instar larvae begin feeding on the flower bud. At the end of the second instar, the larva has consumed or left the flower head. The entire developmental period from egg to pupa takes no more than six weeks. The larvae crawl off the foodplant and pupate on the ground among plant debris. The pupae stay dormant until the following spring, when the next generation of adults emerge.

The number of Vancouver Island populations has been greatly reduced by the development of the Victoria region. In addition, the greatly increased deer population grazes the larval foodplant heavily (CSG). There are still viable populations on some bare rock faces where the larval foodplant, S. spathulifolium, grows abundantly, but this habitat could be seriously damaged by climbers and hikers, such as along the trails on Mt. Finlayson.


Moss' Elfin is found on southeastern Vancouver Island and in the Southern Interior and West Kootenay. It is always found on dry, rocky or scree slopes where the larval foodplant, Sedum sp., grows.



Moss' Elfin is found from southern BC south to southern CA and CO.

Status Information

Scientific NameOrigin StatusProvincial StatusBC List
(Red Blue List)
Callophrys mossiiNativeS4YellowNot Listed
Callophrys mossii mossiiNativeS2S3RedNot Listed
Callophrys mossii schryveriNativeS4YellowNot Listed
BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Additional Photo Sources

General References

Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2021. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2021-10-22 12:23:00 AM]
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