Persius Duskywing

Erynnis persius

The Persius Duskywing is listed as a species of special concern in Wisconsin. Its larval host plant in Wisconsin is Lupine, so it is found in many of the same habitats as the Karner Blue . However, I live in Waushara County and although we have many Karner Blue sites, I had not seen this species until I saw them in Jackson County in 2004.

In 2005, I saw two groups of Persius Duskywings searching for minerals along roadside edges, where Lupine grew. One such group was along a very well-travelled ATV trail, where I was a little concerned for my safety, but the Persius Duskywings appeared to be oblivious to the string of all terrain vehicles zooming by. Several Juvenal’s Duskywing and Sleepy Duskywing joined them at these locations.

Weekly sightings for Persius Duskywing

Identifying characteristics

The Persius Duskywing is a small, dark-brown or black skipper that has four small white hyaline (translucent) spots on the leading edge of the upper forewing that are arranged in a straight row — that is, not offset like other Wisconsin Duskywings. In addition there is usually a single small white spot near the middle of the wing. The male has many white hairs throughout the upper forewing as shown in the close-up image of the forewing. Females lack these hairs and appear much browner with a nearly continuous band through the middle of the wing. The hindwings are very similar to the other Duskywings, with two rows of light spots.

Similar species

This species is most like the Wild Indigo Duskywing and the Columbine Duskywing. It differs from both by having the white spots on the forewing arranged in a straight row. The males of the Columbine and Wild Indigo Duskywings do not have white hairs on the upper forewing like Persius Duskywing males.

The Wisconsin DNR says this about this species, “Sending a specimen to a lepidopterist for microscopic examination is the only way to reliably separate the Persius, Wild Indigo, and Columbine Duskywings.” I do think that is true for the Wild Indigo and Columbine Duskywings because, after studying the literature for some time, I can still not say with certainty that photographs I have classified as Wild Indigo Duskywings are not actually Columbine Duskywings. But after watching and seeing Persius Duskywings for two seasons, I find them the easiest resident Duskywing to identify in central Wisconsin.

Habitat

Pine/oak barrens where the larval host plant Lupine grows.

Flight

A single brood flies from May to early June.

Abundance

I found this species to be more abundant than the other Duskywings in central Wisconsin. At the height of their flight season, I easily see more than 20 in a day.