Pacuvius Duskywing (Erynnis pacuvius) (Lintner, 1878)

Diagnosis: This medium-sized duskywing (wingspan: 29 to 33 mm) has very tiny white forewing markings on a slightly mottled dark brown upperside, and white fringes on the hindwings.

Subspecies: There are four named subspecies, but only subspecies lilius is found in Canada; it was described from Kaslo, British Columbia.

Range: Erynnis pacuvius flies in the southern and western U.S., reaching into Canada only in the southern interior of British Columbia, north to Mt. McLean.


Specimen collection data


Similar Species: The Propertius Duskywing (E. propertius). [compare images]

Early Stages: The larvae are apparently undescribed. The foodplants are all shrubby Rhamnaceae (Ceanothus spp.). In Canada it is reported feeding on Mountain Whitethorn (Ceanothus cordulatus) (Tilden and Smith, 1986).

Abundance: This is an uncommon species in its limited Canadian range.

Flight Season: There is one generation in British Columbia, in June and July, two farther south.

Habits: The Pacuvius Duskywing flies in open woodland and cleared areas, wherever the foodplants are found. It is often seen on flowers and mud, and males regularly perch on hilltops 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.