Regal Fritillary

Speyeria idalia

The Regal Fritillary is considered one of the elite butterflies of the eastern United States. This is partially because the Regal Fritillary has disappeared from many of its former populations in the east and is found in abundance in few locations east of Illinois, and also because fresh butterflies are distinctive, beautiful butterflies. I still get excited whenever I am lucky enough to see a Regal Fritillary.

I have had butterfly enthusiasts from Massachusetts and Ontario, Canada email me about observing this species in Wisconsin. It is endangered in all states east of the Mississippi where it occurs, including Wisconsin and Illinois.

Identifying characteristics

On average, the Regal Fritillary is the largest fritillary in the state with wingspans to nearly four inches on some individuals. The upper forewings are mainly orange with a few black markings and black borders with a row of white spots in the females. The back wing above is very dark with two rows of light spots. In the male, the outer row of spots is yellowish, not white as in the female. Underneath the wing is very dark, chocolate brown with an abundance of white, such that more than half of the wing is actually white.

Similar species

The Regal Fritillary is very different from the other fritillaries when you get a good look at the butterfly, but the Aphrodite Fritillary can be extremely dark below, especially in poor lighting. More than once I have been excited to see a Regal Fritillary that turned out to be a dark Aphrodite hunkered down in the grass. The Regal Fritillary below has much bolder and larger white markings than the Aphrodite.

Habitat

Larger open grasslands and prairie habitat.

Flight

The Regal Fritillary, like the other large fritillaries, has only one generation in Wisconsin, and also has a long flight period, being found from late June to early September.

Abundance

Regal Fritillaries are not common in Wisconsin, being found at a limited number of sites. They are most obvious when actively nectaring on nectar sources such as various milkweeds, thistles, blazing stars, and fall composites. In Great Lakes Entomologist, Vol. 34, No. 1, Ann and Scott Swengel summarized all records of this species from 1970-1999 in Wisconsin.

Locations