The comma butterﬂy is also known as the hop merchant. Its wingspan is about two to two and one-half inches wide. Short, thick projections can be seen along the edge of the hind wings. The upper side of the forewing has a large, dark spot near the bottom edge, and there are several other dark spots on this wing. The light spots along the hindwing edge are enclosed by a dark border. The hindwing is mostly black. The lower side of the hindwing has a small silver or white comma shape that is enlarged at both ends. The larva may be black, green-brown or white. It has black or white spines.
The comma butterfly may be found statewide in Illinois. It lives in woodlands, where it feeds on nettle, false nettle, hops and elms. The life cycle includes egg, larva, pupa and adult stages. Several broods are produced per year. The adult overwinters. This butterfly is active from May through August.