The spicebush swallowtail butterfly is a large, dark swallowtail. It is one of our most beautiful and interesting swallowtails. All developmental stages are great examples of adaptive coloration. The wingspread range is 4.1 to 5.6 cm. The upper surface of the fore wings is black with a narrow marginal row and a broader submarginal row of light yellow row spots. The upper surfaces of the hind wings also have the rows of spots, but they are light green in color. The median areas of the hind wings are dusted with blue in females and blue-green to green in males.