Juvenal's Duskywing (Erynnis juvenalis) (Fabricius, 1793)

Diagnosis: This large dark brown skipper (wingspan: 30 to 37 mm) has white flecks on the costa and two to four white spots on the median part of the forewing. In females the ground colour sometimes takes on a very mottled appearance especially in worn specimens. On the underside, the two round pale spots near the apex of the hindwing are diagnostic for this species.

Subspecies: Only the nominate subspecies juvenalis occurs in Canada.

Range: Erynnis juvenalis occurs throughout the eastern U.S., and in Canada in southern Nova Scotia, and from the Eastern Townships of Quebec through Ontario and southern Manitoba to southeastern Saskatchewan.

Similar Species: Horace's Duskywing (E. horatius) and the Zarucco Duskywing (E. zarucco); both lack the round pale spots on the underside near the apex of the hindwing. [compare images]

Description of this image follows
Juvenal's Duskywing
(Erynnis juvenalis juvenalis), larva.
W. Lukey

Early Stages: The larvae may be various shades of green, with yellowish lateral stripes on the sides and a light brown head. They live in leaf-nests on the foodplants, oaks (Quercus spp.).

Abundance: This is a common and widespread species, and can sometimes be found in large numbers along damp roadsides.

Flight Season: Juvenal's Duskywing flies from early May to late June, with only one generation per year.

Habits: Erynnis juvenalis is more wary and difficult to approach than most dusky wings. It can be seen on the ground basking in the sun, and nectaring, but males are often found perching on oak branches waiting for females.

© 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.