Papilio polyxenes
Plate — illustration to come
ButterflyNative · New Jersey

Black Swallowtail

Papilio polyxenes

Papilionidae

The reason your dill and fennel disappear every August. Larvae are the striking green-and-black striped caterpillars with orange spots that any gardener will eventually meet. The adults are velvet-black with two rows of yellow spots and iridescent blue near the hind wings.

Identify by

How to spot one.

  • 3-inch wingspan

  • Black wings with two bands of yellow spots (males) or blue iridescence (females)

  • Long tails — swallowtail signature

  • Red spot with black pupil on hind wing

Life & behavior

How it lives.

Two to three broods per year. Females lay individual eggs on umbelliferous plants — carrot family. Caterpillars go through a striking transformation from black-with-white-saddle (young) to green-black-orange (mature).

At a glance

The spec sheet.

Type
Butterfly
Active
April – October
Native to NJ
Yes
Conservation status
stable
Family
Papilionidae
Plants it uses

What it needs.

Plants this species visits, feeds on, or depends on. Names in hydrangea link to the plant’s Field Guide entry.

Sources

Xerces Society · NJ Butterflies · Rutgers NJAES