At first glance, skippers look halfway between butterflies and moths. Like other butterflies, many members of this group of small- to medium-sized butterflies are fairly colorful (especially ones that are orange or have elaborate markings), and like most other butterflies, they visit flowers and fly during the day. Also like butterflies, they have club-tipped antennae — but in nearly all skippers, each antenna tip is bent like a hook (this is a key ID character). Meanwhile, like moths, skippers have short, chunky bodies; several species are drab brown, gray, or tan; and many hold their wings flat out to the sides.
Missouri skippers can be easily divided into two general groups: spread-wing and grass skippers.
- Grass skippers, or branded skippers, hold their wings in a characteristic shape that is diagnostic for identifying to their subfamily (Hesperiinae). The forewings are held open in a V shape while the hindwings are held out horizontally (flat) to the side. One author described this as a “jet-plane” shape. Grass skippers may also fold all four wings together so that only the ventral (lower) surfaces are visible. The males of many species have a dark, usually angular patch (called a stigma or a “brand”) on the forewings — the stigma has modified scales that produce pheromones (scents) for attracting females. There are about 130–140 species of grass skippers in North America north of Mexico.
- Examples of Missouri grass skippers include the least, fiery, Leonard’s, cobweb, Peck’s, tawny-edged, crossline, Delaware, Hobomok, and dun skippers, the sachem, and the common roadside-skipper.
- Spread-wing skippers (or open-winged skippers, subfamilies Pyrginae and Eudaminae) generally land with their wings held out flat to the sides. Although sometimes they have all four wings in a slight V, they never hold their wings in the position used by grass skippers, and only rarely hold all four folded together so that only the lower surface is visible. There are about 100 species in these two subfamilies in North America north of Mexico (the spread-winged and dicot skippers used to be grouped in a single subfamily, and some references still treat them as one group).
- Examples of Missouri spread-winged skippers include Hayhurst’s scallopwing, common checkered skipper, common sootywing, and sleepy, Juvenal’s, and Horace’s duskywings
- Examples of Missouri dicot skippers (formerly grouped with the spread-winged skippers) include the silver-spotted skipper, hoary edge, and southern and northern cloudywings.
Larvae: Skipper caterpillars have a remarkably large head, compared to the width of their bodies. Often the head is darker colored than the rest of the body. Just behind the head, their bodies are extra narrowed, which accentuates the head even more. Mostly, they are green, tan, gray, or beige, with no or few hairs.
Similar species: Brush-footed butterflies only walk on 4 legs as adults, while skippers walk on all 6. Geometrid moths typically hold their wings flat and out to the sides, much like the spread-wing skippers, but geometrids usually have rather narrow, not chunky bodies, and they lack the skippers’ distinctive hook-clubbed antennae.