Horace's Duskywing (Erynnis horatius) (Scudder & Burgess, 1870)

Diagnosis: This is another large (wingspan: 28 to 39 mm) dark brown skipper, with small white forewing flecks, larger in females; the females have a slightly mottled appearance.

Range: The range covers almost all of the eastern U.S., but reaches Canada only in extreme southwestern Ontario.

Similar Species: Juvenal's Duskywing (E. juvenalis) and the Zarucco Duskywing (E.zarucco), which has narrower, more pointed forewings. [compare images]

Early Stages: Larvae are not described in detail, but are reported to live in leaf-nests, eating only young leaves. Foodplants are oaks (Fagaceae: Quercus spp.).

Abundance: This is a rare migrant in Canada.

Flight Season: Two generations are reported in the northern part of the range, and three in the south. In Canada records are from the second generation between 14 July and 1 September at Point Pelee and are all worn individuals.

Habits: Horace's Duskywing flies in open woodlands, trails, and clearings, usually near the foodplant, but migrating individuals are most likely to be encountered in Canada along the north shore of Lake Erie.

Remarks: A worn female of horatius was observed at West Beach, Point Pelee National Park, ovipositing on Frost Grape (Vitis riparia) on 13 August 1988. One egg was retained, and the larva fed on Red Oak, but it died after about a week (Hess, 1989). There is no evidence that Horace's Duskywing survives the winter in Canada, or breeds in Canada. Seven of the nine authenticated records for horatius from Canada are from Point Pelee National Park, with single records from Colchester and Rondeau Provincial Park (Alan Wormington, pers. comm.). There are no confirmed records of the first generation in Canada.

© 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.