Pupae overwinter just beneath the soil surface. Adults emerge in late spring and lay eggs on spurge leaves. Adults are gray to tan with a metallic sheen. Wings are fringed and span 18–23 mm. Hatching larvae feed on the undersides of leaves. Larvae are grayish-pink with variable black markings, brown heads, pink warts, and an orange or yellow stripe along each side. They can be up to 13 mm long and develop through four instars before dropping to the soil in fall to pupate. There can be two generations per year in suitable climates. Adults of the second generation emerge in late summer.