Creature Feature: Black Swallowtail Butterfly

April 1, 2020

Female Black Swallowtail

Black Swallowtail Butterfly
Papilio polyxenes

Habitat: The black swallowtail butterfly is native to eastern North America. The butterflies can be found in meadows and fields and are attracted to butterfly bush, phlox, zinnias, purple coneflowers, and milkweeds.

Food: The butterfly feeds on nectar. The caterpillar eats plants in the carrot family: dill, parsley, carrots, and fennel. The caterpillar also likes Queen Anne’s lace.

Behavior: A full-grown caterpillar has an orange horn-like gland on its head called an osmeterium. If the caterpillar senses danger, it releases a foul smell from this gland. The black swallowtail flies faster than other swallowtails.

Male Black Swallowtail

Life Cycle: The female butterfly lays one yellow egg per host plant. After 4-9 days, a caterpillar (larva) hatches from the egg. Over 10-30 days, the caterpillar grows through 5 different stages (called instars) to a length of 2 inches. A young caterpillar is black; an older one is green. The caterpillar then creates a chrysalis (pupa) and metamorphosizes into an adult butterfly after 9-18 days.

Interesting Facts: The black swallowtail butterfly is the official state butterfly of New Jersey. Governor Chris Christie signed the bill in January 2016. The genus name “papilio” is Latin for butterfly. “Polyxenes” is from King of Troy’s daughter, Polyxena, from Homer’s book The Iliad. The female butterflies are typically larger than the males.