The Mottled Duskywing is a medium-sized butterfly in the Hesperiidae family (1). This species is reported from New England to Ontario, the Great Lake states to Colorado and southward to Texas (1, 2), but tend to be more common in the western parts of their range (2). This species was last recorded in Maryland in 1990 (personal comm. Jennifer Selfridge), and currently has a state rank of “X” (Not seen in many years) (3).
The Mottled Duskywing are called spread-winged skippers due to their tendency to rest with wings open and flat (1). This butterfly is mottled brown with darker brown spots on its upperside (1), and a wingspan of 1 to 1 ¼ inches (2). When adults first emerge they have a purple iridescence on their upperwing, especially their forewing (1, 2).
Larvae are pale green with white speckles and are covered in short hairs. Larval heads are black with red, orange, and yellow patches (2). The chrysalis has been known to vary from dark green to brown (3).
For more pictures of the adults and larvae, click here.
The Mottled Duskywing has two broods from May to early August. Females lay their eggs singly on larval host plants, including New Jersey tea (Ceanothus americanus) (3, 5). Larvae will form a shelter by sewing New Jersey Tea leaves together with silk and living inside. They feed at night while storing food for later consumption (1). When larvae are close to maturity they form their chrysalis from leaf litter (1, 3).
As an adult, they visit New Jersey tea (Ceanothus americanus) and dogbane (Apocynum androsaemifolium) (3). Males have been observed on the ground, on the tips of twigs, and perched or patrolling ridges and hills while awaiting females (5).
In Maryland, the Mottled Duskywing was historically recorded in grassy fields, and open woods (3). This species state rank will likely be changed to extirpated, due to the rarity of it's hots plant.
Historical data from Maryland Biodiversity Project and may overrepresent the current range of the species.
© 2020 Price Lab for Entomology, Courtney Rogall