Bog Fritillary

Boloria eunomia

The Bog Fritillary is a species of Wisconsin’s northern bogs. I first found this species at Glocke Lake, a Wisconsin State Natural Area, in Oconto County. This area has an open water bog lake with a fairly wide sphagnum mat. In addition to the Bog Fritillary, the area is also home to fellow northern species Bog Coppers and the Jutta Arctic.

Identifying characteristics

The Bog Fritillary is one of the six lesser fritillaries in Wisconsin. The upper wings on all these smaller species are black and orange, but the Bog Fritillary is very dark, having thicker, black lines and darker scaling throughout, but somewhat lighter spots on the back wing. Underneath, the row of white, submarginal spots is distinctive.

Similar species

Above, the Bog Fritillary is darker than the other lesser fritillaries except for the Freija Fritillary and the Frigga Fritillary. The Freija and Frigga both are dark near the body on the hindwing, while the Bog Fritillary has some obvious lighter spots that are basically the same as the large white spots below.

Below, this species is most like the Silver-bordered Fritillary, but the Silver-bordered Fritillary has a row of black submarginal spots, while in the Bog Fritillary these spots are white and are easily seen on the orange background color.

Habitat

Open bogs in northern Wisconsin.

Flight

One brood. In Michigan they have been found from May 27 to July 2. The Wisconsin DNR web site reports that this species is usually found in mid-June.

Abundance

In Wisconsin this is not a common species, being very local and confined to northern bogs.

Early Bog Fritillary Sightings

Date	County	Reported by
May 26, 2010	Rusk	Kyle Johnson
May 26, 2010	Chippewa	Kyle Johnson
May 28, 2017	Oconto	Douglas Buege
May 31, 2010	Douglas	Ryan Brady
May 31, 2015	Oconto	Scott and Ann Swengel

Locations