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

Satyrium sylvinus Scudder, 1876
Hairstreaks; Sylvan Hairstreak
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

© Norbert Kondla  Email the photographer   (Photo ID #8663)

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Distribution of Satyrium sylvinus in British Columbia.
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Species Information

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Illustration Source: Butterflies of British Columbia by Crispin Guppy and Jon Shepard © Royal BC Museum


The Sylvan and California hairstreaks are very similar in general appearance and cannot be told apart in the field unless closely observed while nectaring. In both, the ground colour of the uppersides of the wings is dark khaki and that of the undersides is khaki. The only consistent difference is the amount of orange spotting in the submarginal area on the undersides of both wings. The Sylvan Hairstreak lacks orange in the submarginal area of the ventral forewing. Orange spotting in the submargin of the ventral hindwing is limited to one conspicuous spot just lateral to the blue spot and a few orange scales elsewhere.

Immature Stages

In California the mature larva is pale apple green with a thin dorsal white line and two diagonal white dashes laterally on each body segment (Comstock and Dammers 1934). Hardy (1962c), however, describes the mature larva as pale green with a dark green dorsal line flanked by yellow on the thorax and white on the abdomen, and with a second yellow line at the spiracles. The pupa is dark mahogany brown.


S.s. nootka Fisher, 1998 (TL: Wellington [Nanaimo], BC) is the BC subspecies.

Genus Description

The name Satyrium is from the Latin saturos (Satyr), a goatlike woodland deity associated with Bacchus. The Satyrs were voluptuous dancers and this generic name draws attention to the sprightly flight of these hairstreaks (Emmet 1991). The common name is derived from the characteristic white "hairline" across the ventral hindwing.

There are usually tails on the hindwings of species in this genus of hairstreaks. The aedeagus of the male is flared at the tip, with a serrated keel. The aedeagus has one or two cornuti, one of which is toothed. The pair of valves are close together at the base but very divergent at the ends. Clench (1961) provided the modern definition of the genus. He did not include in the genus the species S. titus, which has only one cornutus but is otherwise identical to the other species in the genus. Clench indicated that the genus was Holarctic, but authorities in the Palearctic recognize other genera for their fauna, such as Strymonidia, Nordmannia, etc. There are 15 species in this Nearctic genus, seven occuring in BC. The larvae feed on a wide variety of shrubs and perennials, including oaks (Quercus), willow (Salix), buckbrush (Ceanothus), chokecherry (Prunus), saskatoon (Amelanchier alnifolia), and, in one case, legumes.


The Sylvan Hairstreak flies mainly from late June to mid-August. Comstock and Dammers (1934) first noted the foodplant as Salix sp. Hardy (1962c) reared the Vancouver Island populations on Salix prolixa. The butterfly overwinters as an egg and completes development the following spring Hardy (1962c).


The Sylvan Hairstreak is the most widely distributed Satyrium species in BC. Itis known from near Bella Coola and Vanderhoof south throughout the province in riparian situations where the larval foodplant, Salix sp., occurs.



The Sylvan Hairstreak ranges from central BC south to southern CA and NM.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
NativeS5YellowNot 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) 2019. 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: 2020-06-01 2:04:20 AM]
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