Thorybes bathyllus, the southern cloudywing (sometimes spelled southern cloudy wing), is a North American butterfly in the family Hesperiidae. Southern cloudywings can be difficult to identify because of individual variation and confusing seasonal forms. In the south, where it has two broods per year, two seasonal forms occur. Spring forms are usually lightly marked and resemble confused cloudywings (Thorybes confusis). Summer forms tend to be more boldly marked, by comparison, making identification easier. However, summer confused cloudywings are also strongly patterned, which makes identifying them more difficult. Their rapid flight is very erratic, though it is closer to the ground than in some of its close relatives.