Small Wood-Nymph (Cercyonis oetus) (Boisduval, 1869)

Diagnosis: Cercyonis oetus is another dark brown satyrid, whose forewings are more sharply angled at the apex than in the previous two species. There are two eye-spots with white pupils on the forewing in females, with the lower one smaller and closer to the wing margin. In males only the upper eye-spot is usually present. There are usually no hindwing eye-spots. Males have a more contrasting dark stigma on the forewing than in other species and the stigma is more extensive than in Common Wood-Nymph (C.pegala). Wingspan: 32 to 43 mm.

Subspecies: Three subspecies have been named, but only subspecies silvestris is found in Canada. However, the subspecific status of the paler grassland form and the dark montane form is still unclear.

Range: Cercyonis oetus flies in most of the western U.S., and in Canada from southern Saskatchewan to southern British Columbia, and in the Peace River District of BC. It is absent from the west coast, and there is an isolated northern record at Fort McMurray, Alberta.


Specimen collection data

Similar Species: The Common Wood-Nymph (C. pegala) and the Great Basin Wood-Nymph (C. sthenele). [compare images]

Early Stages: The larvae are yellowish or whitish green, with a yellow-edged dark green dorsal stripe and several pale lateral stripes. The head is green and there are two reddish tails. They feed on grasses.

Abundance: The Small Wood-Nymph is common to abundant in the southern part of its Canadian range.

Flight Season: This species flies from early June to mid-September.

Habits: Cercyonis oetus flies in dry open woodlands, scrub, sagebrush, and grasslands; in Saskatchewan and Alberta it prefers very dry short-grass prairie habitat. It is often seen nectaring on flowers.

© 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.