Papilio troilus
Plate — illustration to come
ButterflyNative · New Jersey

Spicebush Swallowtail

Papilio troilus

Papilionidae

The dark swallowtail with the blue-green sheen on its hind wings. Adults are unmistakable, but the caterpillars are the real show — they fold spicebush leaves into little tents and stare out with a pair of huge fake eyespots that are so realistic they'll make you flinch.

Identify by

How to spot one.

  • 3–4 inch wingspan

  • Black wings with pale marginal spots and iridescent blue-green on hind wings

  • Larger orange spot on hind wing than most other black swallowtails

  • Long tails — swallowtail signature

Life & behavior

How it lives.

Two broods per year in NJ. Females lay individual eggs on the undersides of spicebush and sassafras leaves. Young caterpillars mimic bird droppings; mature ones develop the famous fake-eye disguise and stay tucked in folded leaves during the day.

At a glance

The spec sheet.

Type
Butterfly
Active
April – September
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

NJ Butterflies · North American Butterfly Association