
Horace’s Duskywing butterfly.
Photo by Brian Magurn
Loudoun Wildlife had a great turnout for the butterfly walk at Claude Moore Park on July 26. While we were getting started in the parking lot, Brian Magurn pointed out an oak tree in the parking lot with a few skeletonized leaves. Looking closer, we were able to spot a large number of caterpillars and eggs. The iNaturalist app tentatively identified them as Orange-tipped Oakworm Moth caterpillars, Anisota senatoria. The eggs are laid in large clusters, and although they defoliate the leaves, they do little damage to the tree. This is a great reminder of the importance of oak trees, which support some 500 species of Lepidoptera. Returning to butterflies, one of our highlights of the day was seeing three Horace’s Duskywings, which also use oak trees as a host plant.
In all, we saw 43 individual butterflies and 17 species:

Pearl Crescent butterfly.
Photo by Brain Magurn
1 Eastern Black Swallowtail
4 Eastern Tiger Swallowtails
1 Pipevine Swallowtail
1 Spicebush Swallowtail
3 Cabbage Whites
1 Eastern Tailed-Blue
1 Great Spangled Fritillary
1 Mourning Cloak
2 Pearl Crescents
2 Red-Spotted Purple
3 Horace’s Duskywing
8 Silver-spotted skippers
7 Least skippers
3 Little Glassywing
3 Peck’s Skippers
1 Sachem Skipper
1 Zabulon Skipper

