Juniper Hairstreak (Callophrys grynea) (Hübner, 1819)

Diagnosis: A small (wingspan: 20 to 25 mm) hairstreak with an apple-green underside unique in eastern Canada. The slightly smaller western subspecies is more yellow green. The bright white underside postmedian line, regular on the forewing and irregular on the hindwing, is edged with purple inwardly. There are two white spots close to the base in the eastern population and one white spot in the west. The upperside of the tailed wings is dark brown with variable amounts of orange.

Subspecies: The eastern population is subspecies grynea, while in the west subspecies siva is found. Until recently the eastern population was known as the Olive Hairstreak and only the western one was called the Juniper Hairstreak.

Range: Although widespread in the U.S., the Juniper Hairstreak is restricted in Canada to a few scattered locations. Subspecies grynea is locally common in eastern Ontario near Kingston. It used tobe common at Point Pelee and Pelee Island, but has not been seen on Pelee Island since 1918 and virtually disappeared from Point Pelee about 1976. Interestingly, the species made a dramatic recovery at Point Pelee in 1995, when it was common once again. An isolated colony was found near Luskville, Quebec, in 1990, the only known colony for that province. In the west, subspecies siva has been recorded in Saskatchewan in the Frenchman River Badlands.

Similar Species: None in Canada.

Early Stages: The larva is green and bumpy, with oblique white or yellow markings along each side. In the east it feeds on Eastern Red Cedar (Juniperus virginiana). The western subspecies siva eats a variety of junipers, most likely Creeping Juniper (Juniperus horizontalis) in Saskatchewan (Hooper,1973).

Abundance: A very localized and usually rare species in its limited Canadian range.

Flight Season: Throughout most of its North American range, this species is double brooded. In Canada, however, only a single brood has been recorded, from late May through June, except at Point Pelee where it has been recorded in July and August (Wormington, 1983).

Habits: This unique little butterfly does not stray far from its juniper foodplants. It is usually seen on dry hillsides perched on mid-sized foodplant trees. If the trees get too large or the habitat gets overgrown, the butterflies may disappear from that site.

Remarks: It is easiest to discover the presence of this butterfly by shaking the junipers on which it sits. They fly off and most often alight back on the same spot. They frequently perch high on the trees.

© 2002. This material is reproduced with permission from The Butterflies of Canada by Ross A. Layberry, Peter W. Hall, and J. Donald Lafontaine. University of Toronto Press; 1998. Specimen photos courtesy of John T. Fowler.