Specimen of the Month: Small and Mighty Beauties

An excursion to discover the secrets of a pond led a small group through a trail at the edge of Hayward woodlands. Wild roses, brambles, and common milkweed lined the edges before the woods broke to immerse us in the blazing sunlight. As the group turned a corner, a young girl full of spirit pointed to a butterfly and yelled out, “A monarch! There’s a monarch!” Like many, she noticed the beautiful orange wings patterned with black. However, this butterfly was a fritillary, the monarch’s distant cousin. 

While it was impossible to recognize the particular species of fritillary in that fleeting instant, I like to imagine it was one I had just recently become more acquainted with. For the month of July, I asked our bright interns to prepare the Specimen of the Month display. Equally resilient, beautiful, and deserving of our recognition, The Great Spangled Fritillary is one of many butterflies that call the Northwoods home. 

Above, a Great Spangled Fritillary. Below, a Meadow
Fritillary displays similar markings. 

When Museum interns Sarah and Kristina slipped me the piece of paper on which their chosen specimen was written, I admittedly knew little of the species. Speyeria cebele is an important pollinator, but I became fascinated by this butterfly as I discovered just how unique it is. For example, while most butterfly species remain in their adult stage for up to a month, sometimes less, great spangled fritillaries live well over two. Approaching early September, the fritillary braves the dusk of its life with wings often tattered by flight. This species is rather common in the meadows of Wisconsin, and its lengthy life allows for some great sightings.

Now is the perfect time to begin looking for this fritillary. They emerge as butterflies starting in late June to early July, sticking near fields or the edges of woodlands where nectar sources like common milkweed, butterfly weed, mints, and thistles grow. To the untrained eye, great spangled fritillaries appear similar to other orange butterflies. Further distinguishing them between other fritillary species even requires that one can peak at the underside of its wings. That being said, fritillaries are very quick. There are three representative specimens currently at the Museum and I can confirm that it is much easier to notice the slight differences with stationary butterflies.

Silvery spots and a light band along the hind wing help to
distinguish the great spangled fritillary from other similar species.

Often found by nectar sources as adults, great spangled fritillary caterpillars are incredibly particular about their food source. They only feed on the leaves of violets! The mother knowingly lays eggs among debris near patches of violet plants. It is even suspected that she searches out the scent of its dormant roots. Once violet plants emerge in spring, the fritillary caterpillar emerges from the shelter of nearby leaf litter and begins feasting on the delicious leaves. Conspicuous enough in all black with spikey hairs, the fritillary caterpillars evade sighting quite well. They tend to feed on the violet leaves at night, and only from the underside.

Flowers in the Viola genus range in color, with some being bicolored.
Blue and yellow tend to be two shades found on bicolored species. 

Violets are prolific growers, and while that may lead some to consider them weeds, they provide the only food source for the young great spangled fritillary. There are at least 87 violet species in North America, and each have different combinations of brilliant colors. Availability of this plant directly affects the population of fritillaries, and timing between the two species is important too. As our climate evolves, studies seek to determine whether such changes have already affected Speyeria cebele. The synchronization between violets and fritillaries is a beautiful example of small connections in our Northwoods home, and hopefully one that can continue into the future.