The southern dogface butterfly, Colias cesonia, is a yellow butterfly that is also known as the dog's head butterfly. The wings are mostly yellow; there is a small dark eyespot in the center of the forewing and two white spots on the hind wing. The upper side of the pointed fore wings have a dogface pattern. Males have brighter coloration than females. The wingspan is 2 1/4 - 2 1/2 inches (58-65 cm). The caterpillar is green with black and yellow stripes. This butterfly lives in open woods in the southern half of the USA. The larval host plant is the false indigo bush, Amorpha fruticosa (a legume). the southern dogface butterfly belongs to the family Pieridae, genus Colias (Zerene), species C. cesonia.