Atrytonopsis hianna
Grey-brown grass skipper with a frosty, dusted appearance on the hindwing underside. Larvae feed on big bluestem and little bluestem in prairie remnants, barrens, and open woodlands. Widespread but local across eastern and central North America.
Seasonal Activity
Diet
Foliage of big bluestem and little bluestem (larva); adults nectar on a variety of prairie forbs
Lifecycle
One generation per year in the northern portion of its range, with adults on the wing from May to June. In the southern range (including Florida), two broods occur with adults flying from March through October. Eggs are laid on grass blades. Larvae feed on the foliage of native warm-season grasses, constructing silk shelters at the base of clumps. Larvae overwinter as partially grown caterpillars and resume feeding in spring. Pupation occurs in late spring.
Ecology
Native Habitats
Details
Description
The Dusted Skipper (Atrytonopsis hianna) is a medium-sized, subtly coloured grass skipper with a wingspan of 32-43 mm. The upperside is dark grey-brown with a faint pattern of lighter spots on the forewing. The underside of the hindwing is greyish-brown with a distinctive frosted or "dusted" appearance created by a scattering of pale scales — hence the common name. This muted colouration provides excellent camouflage against dry grass and bare soil, making the butterfly difficult to spot when at rest. The body is stout, and the antennae have the characteristic hooked tips of the grass skippers.
Lifecycle
In the northern portion of its range, including Canada, the Dusted Skipper produces a single generation per year with adults on the wing from May to June. In the southern United States, two broods occur with adults flying from March through October. Females lay eggs singly on grass blades of the host species. Larvae feed on the foliage of native warm-season grasses, primarily Big Bluestem (Andropogon gerardii) and Little Bluestem (Schizachyrium scoparium). They construct silk-tied shelters at the base of grass clumps and feed nocturnally. Larvae overwinter as partially grown caterpillars in their shelters and resume feeding in spring before pupating in late spring. The early flight period makes this one of the first grass skippers to appear each season.
Ecology
The Dusted Skipper is closely tied to native warm-season bunchgrasses, making it an indicator of prairie and barrens habitat quality. Adults nectar on a variety of prairie forbs, though specific nectar preferences are less well documented than for many other skippers. Males perch on low vegetation in open, grassy areas to await females. The species' dependence on Big Bluestem and Little Bluestem — both keystone prairie species — means its distribution closely tracks intact grassland and savanna remnants. Habitat loss, fire suppression, and conversion to cool-season pasture grasses are the primary threats, though the species remains relatively secure across its broad range.
Host Plants
Larvae are specialists on native warm-season bunchgrasses, with two primary hosts documented across most of the range.
- Big Bluestem (Andropogon gerardii)
- Little Bluestem (Schizachyrium scoparium)
Habitat
Ranges from eastern Wyoming and Colorado east to New Hampshire and Massachusetts, south to Florida and the Gulf Coast. In Canada, it occurs in southern Ontario in tallgrass prairie remnants, oak savannas, dry barrens, and open woodland edges where native bunchgrasses persist. The species prefers dry to mesic sites with sparse to moderate grass cover and some exposed soil. NatureServe ranks the species as G4 (Apparently Secure). While not listed under the Species at Risk Act, its dependence on declining native grassland habitat makes local populations vulnerable to extirpation.