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Horace’s Duskywing

Erynnis horatius
Family: 
Hesperiidae (skippers)
Description: 

Males and females have white spots on the forewing, including a white spot in the forewing cell (the oval space between veins that is toward the leading edge of the forewing, near the body); white spots are larger on females. Overall color is brown without a hint of gray. Males have a bold white line over the eye.

As a spread-winged skipper, this species most often rests with all four of the wings held out flat to the side.

Similar species: The ventral (lower) side is the easiest way to separate this species from Juvenal’s duskywing (Erynnis juvenalis): Juvenal’s has two pale spots toward the tip of the ventral hindwing. Also, by late May, the Juvenal’s duskywing has disappeared; after that, Horace’s is the only duskywing in Missouri with a white spot in the forewing cell.

Larvae are bluish-green with tiny, light-colored spots; head is brown with orange blotches around the margin; body tapers at the end.

Size: 
Wingspan: 1¼–1½ inches.
Habitat and conservation: 
Flies in forest clearings and edges, brushy fields, roadsides and yards. The adults are very often seen on flowers and at mud puddles.
Foods: 
Larvae feed on the leaves of oaks. The adults frequent flowers that are about 4 feet tall, including buttonbush, dogbane, goldenrod and others in the sunflower family, plus mints and mustards.
Distribution in Missouri: 
Statewide.
Status: 
Resident with multiple broods.
Life cycle: 
Flies from late March until mid-October. The life history is similar to other duskywings. Males visit puddles shortly after emerging, then perch on twigs to intercept passing females. Females lay eggs singly; caterpillars feed on young leaves, taking shelter in leaf nests when not actively feeding. Fully grown caterpillars overwinter in their nests in the leaf litter below the tree and pupate in their nests in spring.
Human connections: 
Skippers are technically neither butterflies nor moths, although they are more closely related to butterflies than to moths. Taxonomists are biologists who study the names of organisms and the relationships among them. Today taxonomists use the tool of DNA evidence to refine our knowledge.
Ecosystem connections: 
The caterpillars are herbivores that graze on vegetation. The adults serve a role in pollination. All stages provide food for predators.
Shortened URL
http://mdc.mo.gov/node/18263