Butterfly: Wingspan: 1 3/4 - 2 3/4 inches (4.5 - 7 cm). Upperside is black with red-orange crescents on outer margins of both wings and rows of creamy white spots inward.
ID Tip: Black with red orange patches along both wing margins
Egg: Yellow, soon turning reddish. The tiny, round eggs are laid in large clusters that may number several hundred. Clusters are placed on the underside of host leaves.
Caterpillar: Dusky orange with black stripe and several rows of branched black spines. Front and rear segments are black. The overwintering stage.
Chrysalis: Creamy white with orange and black markings.
Baltimore Checkerspots have only one flight each year, typically beginning in late spring/early summer. For many years, throughout their range, turtleheads (Chelone spp.) were the only known host plants; then Baltimore Checkerspots were discovered in dry, upland areas using false foxgloves as their caterpillar hosts. Among taxonomists, there is debate about whether there are different subspecies(and if so, how many?) or whether these differences may constitute two different species. Until 2016, only a few extremely localized colonies of false-foxglove eaters had been documented in Alabama. Then Mary Jane and Steve Krotzer discovered a population of Baltimore Checkerspots near Cullman using White Turtlehead as their caterpillar host and already flying in April--practically unheard of for this species. In 2017, the butterflies were once again on the wing in mid-April. Alabama's Baltimore Checkerspots should be carefully observed and monitored to better understand their genetic makeup as well as their conservation needs.
The brilliant colors that we find so beautiful in Baltimore Checkerspots are alarming to many predators. These butterflies are unpalatable to birds, and the distinctly colored checkers serves a a warning signal. The source of Baltimore Checkerspots' toxicity originates with their host plants--members of the Figwort family that are known for their iridoid compunds. Like many protected butterflies, Baltimore Checkerspots are slow, deliberate fliers. Both sexes perch on low vegetation with open wings, and males congregate in puddle clubs.
Checkerspot females deposit clusters of several hundred tiny yellow eggs on the undersides of host leaves. The eggs turn red as they age. Newly hatched larvae migrate to the tops of plants where they spin webs and feed communally. They gradually increase the size of the web to include more and more plant material, wandering away from the nest at times, but always returning to its safety. In late summer, they stop feeding and reinforce the web. The longtime assumption was that this became the winter nest, but the structure actually functions as a pre-hibernation site. Most caterpillars move out of it in fall and descend into the leaf litter at the base of the plants where they overwinter. Warmer temperatures and longer day lengths trigger a return to eating and activity, but neither host plant may have sufficient spring foliage to support the voracious appetites of the growing caterpillars. In an unusual adaptation, many larvae finish their development on other herbaceous plants, which may also contain iridoid compounds.
A dot on the county map indicates that there is at least one documented record of the species within that county. In some cases, a species may be common throughout the county, in others it may be found in only a specific habitat.
The sightings bar graphs depict the timing of flight(s) within each of three geographic regions. Place your cursor on a bar within the graph to see the number of individuals recorded during that period.
The abundance calendar displays the total number of individuals recorded within each week of the month. Both the graphs and the calendar are on based data collection that began in 2000.
The records analyzed here are only a beginning. As more data is collected, these maps and graphs will paint a more accurate picture of distribution and abundance in Alabama. Submit your sightings to email@example.com.
Sightings in the following counties: Blount, Cullman, Jackson, Jefferson
Wet meadows, bogs, stream banks, marshes OR upland dry areas in or near oak woodlands.
These host plants have been verified in Alabama:Smooth Yellow False Foxglove (Aurea flava var. flava) and White Turtlehead (Chelone glabra).
For more information about the documented host plants and/or nectar plants, please visit the Alabama Plant Atlas using the following links: