The adult Spicebush Swallowtail (Papilio troilus) is a relatively long-lived butterfly. It is very common in the Philadelphia area. It is so large that it hard to miss. Let’s study the life cycle of this big beautiful butterfly.
The eggs are plain and spherical and can be found on the species’ host plants. Host plants are the plants that the larva is able to digest. Each species of butterfly has specific plants that it can eat. These are almost exclusively native plants. Why should we plant native plants in our gardens?
The Spicebush Caterpillar
The young larvae resembles a bird dropping. It feeds at night and lives in a folded-over leaf shelter.
The mature caterpillar continues to feed at night and rest during the day.
The mature caterpillar has “snake head” eyespots. It lives in a silk-covered leaf tube. It will turn yellow before pupating. Two most common host plants are Spicebush and Sassafras.
Video of a Spicebush Swallowtail Caterpillar
After the caterpillar reaches maturity it spins a chrysalis and metamorphosizes into an adult butterfly.
Spicebush, the Preferred Hostplant
The Spicebush (Lindera benzoin) blooms in early spring. The leaves which appear later feed Spicebush caterpillars. The caterpillars will also eat Sassafras (Sassafras albidum) leaves. The caterpillars fare better eating Spicebush leaves than Sassafras leaves. The Sassafras Tree blooms in spring with yellow-green little flowers.
Spicebush Butterfly Adult
The Spicebush adult is a large dark pigmented butterfly. It used to be called the “Green-clouded Swallowtail” because of the the greenish area on the hind wings. It is often confused with the Black Swallowtail. I confuse it all the time.
The hind wings have two rows of light colored spots along the wing edges. At the back center of the hind wings, where the left and right wings meet, there are two orange spots.
The forewings are dark along the front edges and have white spots along the sides.
Males Spicebush roam woodland and woodland edges looking for receptive females. They mate in flight with the male hovering over the female. This species courts and mates in the afternoon.
The male butterfly will congregate in “puddling” groups.
The Spicebush or a Pipevine Butterfly or Red-spotted Purple?
I always get these butterflies confused. I include them so you won’t be. First up is our focus the Spicebush Swallowtail. Next is the Pipevine Swallowtail and then the Red-spotted Purple.
Spicebush Swallowtail Butterfly Facts
- Family: Papilionidae (Parnassians and Swallowtails) – Spicebush is one of the 12 Swallowtail species on the East Coast.
- Range: Eastern United States. The species is declining in the far South. It is gone from the Florida Keys.Wingspan: 3 1/2 – 4 1/2 inches across (89 – 114 mm)
- Hostplant: Primarily Spicebush (lindera benzoin) but also Sassafras (Sassafras albidum) and bays. The larvae fare better on Spicebush than on Sassafras.
- Habitat: Generalist – woods, woodland edges, roadsides, fields, swamps and parks.
- Flight: low-flying, 3 – 9 feet above the ground with fairly rapid wing beats. The adults are strong fliers which can fly across sizable bodies of water.
- Nectar: Adults have long proboscises which enable the butterfly to sip nectar from deep blossoms.
- Eggs: Generally plain and spherical