Belle Isle Conservancy
The Baltimore Checkerspot (scientific name Euphydryas phaeton) is a small butterfly with a wingspan of 11⁄2 to 21⁄2 inches. It looks like a “miniature Monarch” with black, orange and white spotted wings in a specked or checkered pattern. Their caterpillars have similar coloring, banded with black and orange with black spikes. They lay yellow eggs in clusters of 100 – 700 on the undersides of host plant leaves. The Slender False Foxglove is a host plant for these butterflies. Young caterpillars hatch after about 20 days and congregate in a web they construct of silk on the host plant where they live and feed. Unlike most butterfly larvae, Baltimore Checkerspot larvae over winter grouped in leaf litter at the base of the host plant. When they emerge in late April or early May, they continue feeding until they form a striking chrysalis that is white with orange and black markings. Adults hatch from the chrysalis after about 10 days. You may see them flying close to the ground in areas where there are summer flowering plants that the adults like to eat. Some of these plants, such as Dogwood, various kinds of Milkweed, Blackeyed Susan, and Queen Anne‘s Lace are also found on Belle Isle.
The Baltimore Checkerspot is seen most commonly in the Northeastern United States and Canada. It is increasingly rare in more southerly areas, most notably Maryland, where it is the official state insect. Like the Slender False Foxglove these little butterflies prefer both wet and dry meadows, and bogs, which are areas threatened by man-made changes to the environment.