Black Swallowtail

Papilio polyxenes are found from southern Canada through to South America. In North America they are more common east of the Rocky Mountains. They are usually found in open areas like fields, parks, marshes or deserts, and they prefer tropical or temperate habitats.

Females lay single eggs on host plants, usually on the new foliage and occasionally on flowers. The eggs stage lasts 4–9 days, the larval stage 10–30 days, and the pupal stage 18 days. The duration of these stages may vary depending on temperature and the species of the host plants. Feeny et al., 1985 finds that survival of eggs and larvae of P. polyxenes varies depending on the location (near Ithaca, New York) where the eggs were laid. Eggs laid on wild carrot or parsnip plants were more likely to survive to the fifth instar than were eggs laid on poison hemlock. Eggs laid on plants at elevations of 300 to 435 metres (984 to 1,427 ft) above sea-level were more likely to survive than eggs laid at 120 meters above sea-level. There were also significant differences in survival rates between early and late broods in a year, and between years. In all cases, the primary cause of mortality was predation.

Emergence. Winter is spent in the chrysalis stage, and adults will emerge in the spring to seek out host plants. Adults will emerge in the mornings on a daily basis. First brood adults will fly from mid-May until late June, second brood adults will fly from early July until late August, and occasionally a partial third brood will occur that will emerge later in the season.

Life expectancy. …

Papilio polyxenes use a variety of herbs in the carrot family (Apiaceae), but will choose the food plants for their larvae based on visual and chemical variations. Host plant odor is one of the cues involved in the selection of landing sites for oviposition. The responses to these cues are innate, and feeding on a host plant as a larva does not increase the preference for that plant as an adult. Species of host plants include:

American angelica, Angelica atropurpurea Hairy angelica, Angelica venenosa Dill, Anethum graveolens Cutleaf waterparsnip, Berula erecta Spotted water hemlock, Cicuta maculata Canadian honewort, Cryptotaenia canadensis Queen Anne's lace, Daucus carota Wedgeleaf eryngo, Eryngium cuneifolium Fennel, Foeniculum vulgare Cow parsnip, Heracleum maximum Lovage, Levisticum officinale Cucumber magnolia, Magnolia acuminata Sweetbay magnolia, Magnolia virginiana Sweet cicely, Osmorhiza claytonii Long-styled sweet cicely, Osmorhiza longistylis Canby's dropwort, Oxypolis canbyi Water cowbane, Oxypolis filiformis Parsnip, Pastinaca sativa Parsley, Petroselinum crispum Mock bishopweed, Ptilimnium capillaceum Rue, Ruta graveolens Water parsnip, Sium suave Roughfruit scaleseed, Spermolepis divaricata Yellow pimpernel, Taenidia integerrima Northern prickly ash, Zanthoxylum americanum Golden alexanders, Zizia

The Papilio polyxenes was named the official state butterfly of New Jersey on January 11, 2016.