The mourning cloak butterﬂy has a wingspan of two and one-half to three and three-fourths inches. It has a dark brown-to-black body. The upperside of the wings is dark brown edged with a yellow band that has a row of blue spots on its inner border. The caterpillar is black with tiny white ﬂecks, a row of dull red spots on the back and black spines.
The mourning cloak butterﬂy lives in woodlands, swamps and parks although it can be seen wandering in many other areas. This insect may be found statewide in Illinois. The adult probably lives longer than any other butterﬂy, being active for 10 to 11 months. The adult overwinters and may be seen on any day warm enough for ﬂying. The larva eats the leaves of willow, cottonwood, birch, elm and hackberry.