This large beautiful butterfly is the Great-Spangled Fritillary (Speyeria cybele). They are found throughout most of North America in open fields, prairies, backyard gardens, and large open areas. Males are tan to orange in color with black scales on the forewing veins. Females are tawny colored and darker than males.
The adults nectar at a wide variety of flowers including verbena, vetch, red clover, milkweed and thistle. The caterpillars are like other fritillary's and feed on violets. This species is the largest fritillary in Missouri as well as all of Eastern North America. In their western most range they are less common and some specialist even refer to them as a separate species called Leto Fritillary. They have a wingspan of 2 to 4 inches. They're flight is somewhat rapid, as they fly from flower to flower, pausing briefly to nectar.They are quick to fly which can make them difficult to approach.
Males will patrol for females. Once a receptive female has been found, mating will occur. This usually takes place in June or July. Sometime in August or September the females will lay eggs on or near the host plant, violets.. When the eggs hatch the young caterpillars will overwinter under leaf litter and vegetation. In the spring they will become active and seek out the violets to feed on. They somehow manage to find the violets, by some pre-programed instinct. They feed at night, and hide out during the day. This preference for feeding times probably gives them a certain amount of protection from predation. Birds and other insects that might find a fritillary caterpillar tasty to dine on, are all tucked away sleeping while these little munchers are pigging out on their late night meals.
These are impressive, beautiful flying flowers, and I love to see them return each year.