Background and Description of Silver-spotted skipper 

The silver-spotted skipper, Epargyreus clarus (Lepidoptera: Hesperiidae), is a widely distributed species throughout the United States. This species sometimes reaches high population levels in Louisiana or other states around the Gulf of Mexico, which requires the application of insecticides. In Kentucky, silver-spotted skipper caterpillars can be observed in soybean fields. We observed higher populations and leaf injuries of this species in soybean fields in central Kentucky during the 2024 season than in previous years. 

Early instar Silver-spotted skipper caterpillars cut and fold sections of leaves around their bodies, forming a shelter to protect them from predators (Figure 1), and later instar caterpillars build their shelters by silking several leaves together. Thus, the easier way to detect them in the field is looking for leaves with borders cut and folded (Figure 1) and for groups of leaves silked together.

The caterpillar has a reddish-brown head with two eyelike yellow or orange spots. The head is wider than the prothorax; this latter characteristic makes it look like it has a “neck” (Figure 2).

The body is light green with darker transverse stripes with reddish legs and yellowish-orange abdominal “prolegs,” and late instar larvae can reach up to 2 inches in length (Figure 3).

Adult silver-spotted skippers are relatively larger compared with other skipper species, with a wingspan ranging from 1.75 to 2.5 inches. The wings are brownish with a row of orange spots that are visible from both the under and the upper sides of the forewing (Figure 4a). The hind wing has a distinct silver-whitish spot on the underside, which is visible in a resting position and gives it the common name of silver-spotted skipper (Figure 4b).

Management The larvae of the silver-spotted skipper feed on several plant species of the family Fabaceae, including soybeans; however, there are no records of significant losses caused by this species in soybean fields in Kentucky. Despite the shelter, biological control by parasitoids, predators, and entomopathogens such as baculovirus are known to have an impact on the caterpillars; thus, it is unlikely that an intervention would be necessary to avoid losses by the silver-spotted skipper in soybean crops in central Kentucky. 

Optional Citation: Batista , F.. Villanueva R. 2025. Abundance of the Silver-Spotted Skipper in Soybeans in Kentucky in 2024. Kentucky Field Crops News, Vol 1, Issue 1. University of Kentucky, January 17, 2025.