The viceroy butterfly is from the family Nymphalidae. It is a brown and orange non-poisonous butterfly that is very similar to the monarch; it is a batesian mimic of the poisonous monarch. It can be distinguished from the monarch by the black line that crosses its wings. Also, the undersides of its wings are quite similar to the topside (unlike the monarch, whose underside is much lighter). It has a wingspan of 2.75 to 3 inches (7 to 7.5 cm). The viceroy is found from Canada to Mexico. The caterpillar is olive green and brown with bristly tufts behind the head; it eats mostly willow and cottonwood.