Papilio polyxenes
Identification: Large—about 3.2” (smaller than Spicebush Swallowtail). Above: Male FW and HW mostly black and yellow, with a prominent line of large yellow spots across both wings as well as smaller submarginal yellow spots. Females have bright blue on HW near tail and the rows of yellow spots on the FW are smaller. On both sexes, note pale spot near front edge of FW just inward of yellow spots (Spicebush lacks this spot). Below: Black, yellow, orange, and blue. HW has two bands of orange spots, with the inner band normally complete (this band is interrupted on Spicebush). Flies faster than other swallowtails.
NJ Status and Distribution: Resident. Common and widespread throughout but generally less common at the higher elevations in the Highlands and Ridge and Valley provinces.
Habitat: Open, sunny upland fields, including disturbed areas. Easily attracted to gardens with flowers such as Butterfly Bush, Purple Coneflower, and milkweeds, and with its host plants.
Flight Period: Early April to mid-October with peaks in May and July. Extreme dates: North Jersey 4/7—10/19; South Jersey 3/17—11/30.
Caterpillar Food Plants: Plants in the Carrot Family such as the native Golden Zizia (Zizia aurea) and non-native Queen Anne’s Lace (Daucus carota) and garden herbs Parsley, Dill, Fennel, and Common Rue.
Overwintering Stage: Pupa.
Good Locations: Whittingham WMA, Schooley’s Mountain CP, Merrill Creek Reservoir, Willowwood Arboretum, Bamboo Brook Outdoor Education Center, Great Swamp NWR, Kay Environmental Center, Forsythe NWR (Brigantine Division), Cape May Point SP.
Comments: Gardeners who plant Parsley and similar species will reap the pleasure of seeing both these lovely butterflies and their cool caterpillars.
Male, Walpack Twp. (DWGNRA), Sussex Co., NJ, 7/11/08, on Common Milkweed.
Female, Kittatinny Valley SP, Sussex Co., NJ, 8/15/12 on Butterflybush.
Fredon Twp., Sussex Co., NJ, 8/18/08, on Purpletop Verbena.
First instar caterpillar.
Third instar caterpillar eating previous instar skin.
Mature caterpillar starting to pupate.
Green pupa, Sussex Co,, NJ, 4/14/17.
Brown pupa, Sussex Co., NJ, 4/14/17.
Golden Zizia, a native caterpillar food plant for Black Swallowtail.
Queen Anne's Lace—a non-native that is one of several caterpillar food plants for Black Swallowtail.