Family Hesperiidae Rank Species | ||
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Similar Erynnis afranius, Polites sabuleti, Pyrgus scriptura, Thorybes mexicana, Hesperia uncas | ||
Hesperopsis libya, the Mojave sootywing, Mohave sootywing, Great Basin sootywing or Lena sooty wing, is a butterfly of the Hesperiidae family. It is found in North America from eastern Oregon east to Montana and south to southern California, Arizona, and north-western Mexico including Baja California.
The wingspan is 22–32 mm. The upperside is dark brown with two rows of small white spots on the forewings. The underside of the hindwings is light to dark brown with a pale grey overlay and some white spots. Adults are on wing from July to August in one generation per year in North Dakota and Montana. In Colorado, there are two generations with adults on wing from June to August while adult are on wing from March to October in multiple generations in California. Adults feed on flower nectar.
The larvae feed on the leaves of Atriplex canescens. They live in nests of leaves tied together with silk.