Polydamas Swallowtails

The Polydamas Swallowtail is also known as the Gold-rim and the Tail-less Swallowtail. This species hosts on Pipevines (Aristolochias) and is found through Central and South America as well as peninsular Florida, southern Texas and the Bahamas.

By consuming Pipevine plant species, Polydamas Swallowtails take in the aristolochic acids in the leaves and become distasteful to predators. Just like Pipevine Swallowtails they are often avoided by predators and may be a Batesian model in the Swallowtail mimicry complex in some parts of their range.

Eggs and Larvae: Eggs are laid in clusters, usually on the newest growth of Pipevines. Egg clusters usually have 10-14 eggs each but can have fewer if the butterfly is interrupted or frightened off while ovipositing.

The young caterpillars are gregarious and feed together in small groups after hatching from their eggs. These groups will travel together from leaf to leaf but begin to split up as the caterpillars grow larger and need more food. Polydamas Swallowtails have voracious appetites and eat rather quickly. They can also be quite messy, chewing on leaves and detaching them from the vines where they will drop to the ground, uneaten.

Caterpillars with a tan: Larvae of the Polydamas Swallowtail found outside on Aristolochia have a striped brown on darker brown appearance with short orange-red tubercles. Larvae reared indoors are a deep uniform brown, almost black in color and have short tubercles that are more bright red in color.

As the only difference for these larvae is the presence of sunlight, I can only figure that the UV present in sunlight may help to bring forth this coloration in wild caterpillars. Larvae brought inside for rearing lose this coloration in a few days and will appear nearly black in color. Any further information on this color change would be greatly appreciated.

Pupa: Chrysalis of the Polydamas Swallowtail can be found in both green and brown forms. Green chrysalis are more prevalent when located among foliage. Brown chrysalis are often found on tree bark or close to the ground. These coloration differences help to better camouflage the developing butterfly inside. This species can enter into a state of hibernation called diapause and overwinter as a chrysalis.

Adults: Unlike most swallowtails, the adult Polydamas Swallowtails lack the hind wing protrusions for which the butterfly family is named. Mostly black in color, the butterfly has yellow markings that edge the bottom of its lower wings.

In years with a mild winter, you can find Polydamas Swallowtails nearly throughout the year. After this past harsh winter the population seem to have taken some damage as they have only returned to the gardens in the past month or so.

Photo Credit: Chrysalis Photo by T.J. Couch