Euphyes dukesi-Cedar Herald Index

Euphyes dukesi, or Dukes' skipper, is a butterfly of the family Hesperiidae. It lives in the eastern United States and in a small portion of southern Ontario, Canada, in three distinct populations. Preferred habitats are shaded wetlands (woodland or coastal swamps, marshes, and ditches), with various species of sedge plants it uses as host plants for its larvae.

Description

They have short, rounded wings with a wingspan of . The wings of both sexes are deep brown on top, and the underside of the hindwings are light brown with pale yellow rays. They are similar in appearance to other Euphyes, but "the single yellowish streak on the hindwing beneath is unmistakable." Females are slightly larger than males and have a hindwing band with two to three pale yellow spots, while males have a black stigma on the forewing. Caterpillars have a light green body with a black head.

Euphyes dukesi

For male genitalia have "five toothed processes at the terminus of the aedoeagus."

Euphyes dukesi

Naming

The species was named for W. C. Dukes of Mobile, Alabama, in Arthur Ward Lindsey's original 1923 description of the species, "in acknowledgment of his unselfish efforts to advance our knowledge of the Lepidoptera of Alabama." The first specimen was collected by Dukes on August 6, 1922, in Mobile County, Alabama.

Euphyes dukesi

Distribution

Dukes' skipper is found in scattered locations around the eastern United States and a small portion of southeastern Canada. There are three distinct regionally clustered populations: Along the Atlantic Coast from southeastern Virginia to northern peninsular Florida. The lower Mississippi Valley from central Missouri and southern Illinois south to the Gulf Coast. Extreme southwestern Ontario, southeastern Michigan, northeastern Indiana, and northern Ohio.

Its full distribution consists of the Canadian province of Ontario and the following US states: Alaska, Arkansas, Florida, Georgia, Illinois, Indiana, Kentucky, Louisiana, Michigan, Missouri, Mississippi, North Carolina, Ohio, South Carolina, Texas, and Virginia.

The split distribution between coastal plains and the Great Lakes area is unusual for North American butterflies, and it is hypothesized that it may be due to population displacements during the Pleistocene glacial intervals, followed by dispersal through the vegetational corridors of the Mississippi and Mohawk valleys when the ice sheets retreated.

Life cycle

Eggs are laid singly under the leaves of the host plants on which the larvae feed. Larvae molt several times, diapause to overwinter in their fourth instar, feed again and molt once more in the spring, then pupate for about two weeks before emerging as adults. Its adult lifespan is estimated at three weeks, and its total lifespan from hatching is about a year or less.

Broods

The species ranges from univoltine in the north to trivoltine in the south, with flight periods lasting approximately one month. In northern populations, the species typically has a single brood around July. From western Kentucky and Virginia southward, it has one brood around June and a second brood around August to September. In Florida, the subspecies E. dukesi calhouni may have more than two broods, from mid-May through October.

Food

Host plants used by larvae are restricted to various sedges of the genera Carex and Rhynchospora. These include hairy sedge Carex lacustris in the north (particularly in shaded wetlands, including coastal swamps and ditches), shoreline sedge Carex hyalinolepis in the south (Mississippi River basin), false hop sedge Carex lupuliformis, Carex walteriana, Walter's sedge (Carex striata) in the southeast, narrowfruit horned beaksedge (Ryncospora inundata), and millet beaksedge (Rynchospora miliacea) in Florida.

Adults feed on flower nectar of various plants including buttonbush (Cephalanthus occidentalis), common milkweed (Asclepias syriaca), swamp milkweed (Asclepias incarnata), Joe-Pye weed (Eupatorium maculatum), blue mistflower (Eupatorium coelestinum), pickerelweed (Pontederia cordata), hibiscus species (Hibiscus), sneezeweed (Helenium autumnale), alfalfa (Medicago sativa), and red clover (Trifolium pratense).