The lifecycle of the Regal Fritillary is a yearlong process. As with all butterflies, it starts with a small egg. Eggs are ovular and yellow. Females lay up to several thousand of them haphazardly near various species of violets in mid-September. The female needs all these eggs as only a fraction of the caterpillars makes it through the winter.

The young larvae hatch from the egg a quarter the size of one's pinky nail 7-14 days later. This young caterpillar eats its eggshell and travels to nearby violets to enter a stage of extended diapause based on amounts of daylight. The caterpillar is highly temperature and snow resident in order to survive the midwestern winters. Around mid-April, the caterpillar awakes and promptly begins feeding. This next stage will last around 4 weeks, but it is heavily dependent on the weather. The small caterpillar that emerged in the fall has grown 2000% and the size of an adult person's thumb by late May. The larvae is now heavily armored with rows of barbed spines on the backside.

Around the beginning of June caterpillars build little nests around their Violet hosts and shed into a large, dark brown pupae. The chrysalis stage will last 2 weeks for males and around 3-4 for females. Around the 3rd of June to mid-July adults will emerge in full swing.

Males always emerge earlier than females. After spending a day laying low, they take to the air and begin their aerial battle and patrol with other males. Males are often seen flying briskly in a relatively straight line, weaving through grass and landing on nectar sources. Adults seem to prefer various Milkweeds and Coneflowers. The large and beautiful females finally emerge at the end of June and into July. Females have a much different temperament. Typical of greater Fritillaries, they are shy and reclusive. They spend much of the day hiding in tall grass and forest edges, only leaving for feeding. Lucky males will pair with females in July. Mating is usually done in hidden, shaded places where other males will not try to separate them. Males may try to pair multiple times, but they usually die out by mid-August. After mating, females fall into a reproductive diapause which prolongs their lifespan. They can live up to 3-4 months in the wild if weather permits. Females lay eggs again in mid-September and start the lifecycle all over again. Most adults will perish during the first frost. 

Quick Facts

- Wingspan: 3.5-4.25 inches (female is larger)

- Lifespan of adults: 1-4 months

- Host plants: Various species in the Viola genus. Can also feed on Pansies. 

- Habitat: Large, open mixed-grass and tall-grass prairies where host plants are present.

- Status: Varies by state. Extirpated in various eastern states but still secure in the Great Plains. 

Gallery

Regal Fritillaries exhibit subtle sexual dimorphism. Females (on the left) are larger and have 2 rows of white spots on the dorsal hindwing. Males are slightly smaller with a bottom row of orange spots on the dorsal hindwing and have lighter wingtips. The image of the female is credited to the Pennsylvania National Guard and the image of the male is from Andy Reago and Chrissy McClaren. 

Image of Confederate Violets taken by Ronald Douglas Frazier. The image of the 5th instar caterpillar was taken by Thomas J. Allen. 

These Fritillaries are rare aberrant forms. This usually occurs with a severe temperature change during the pupal stage. The left image is credited to Spectrum News 1 and the right image was taken by Mike Reese.