Caterpillar: Black Swallowtail

Black Swallowtail caterpillar

Some bugs can be pretty scary, but not caterpillars they are amazing! These small insects can transform themselves into beautiful butterflies or moths. Each year, somewhere around my house, I find a caterpillar I have never seen. Before it wanders off I run and grab my Peterson’s First Guide to Caterpillars of North America, to see if I can identify which caterpillar it is. Luckily most of the ones I see are pretty obvious, like the one I saw last week (see above). This caterpillar was hanging out in my garden on my rue and after a few turn of the pages I identified it as a Black Swallowtail (Papilio polyxenes asterius).

Black Swallowtail Butterfly

The Black Swallowtail caterpillar sometimes called the Parsley caterpillar, is identified as black with a white saddle as a young larva and green, smooth with black bands and yellow spots as an adult larva.

The most interesting thing about the Black Swallowtail caterpillar is that it absorbs the toxins of the plant it eats to make itself bad tasting to predators, no I didn’t try it. These bad tasting plants are from the carrot family, such as Queen Ann’s lace, carrot, parsley and dill.

Many chrysalis overwinter and emerge as butterflies in the early spring. While other butterflies lay eggs, which hatch into the larva (caterpillar). After molting several times, it then transforms into a pale green chrysalis that hatches into a beautiful butterfly. The butterfly is identified as being black with white spots along its wing-span, which can reach up to 4 1/2 inches.

After you have identified your caterpillar, write it in down on the page in your caterpillar book. It will be fun to look back and see, “June 30, 2011 saw in my garden on my rue plant, took pictures”.

Male Black Swallowtail Butterfly

Have you seen any caterpillars or butterflies this year? Share your photographs and stories with us, we would love to see them!

One Response to “Caterpillar: Black Swallowtail”
  1. That is a gorgeous larva, even prettier than its adult! I have a patch of parsley that’s bolted .. I’ll wait and watch to see if any black swallowtail larvae appear. Love the idea of a caterpillar book!

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: