Black Swallowtail vs. Spicebush Swallowtail butterflies

One of our WAGC members’ friends recently took a photo a caterpillar that she found in her garden. Not knowing what it was, she contacted Rutgers University and they unfortunately mis-identified it as a Black Swallowtail caterpillar (photo 1). WAGC member (and butterfly breeder) Joan Rottkamp saw the photo and immediately knew what it was – a Spicebush Swallowtail caterpillar (photo 3). The two are not very similar in appearance as caterpillars, but are quite similar as butterflies (photos 2 and 4). The Black Swallowtail feeds on parsley and dill host plants and the Spicebush variety hang out on sassafras and what else – spicebush plants.

Thanks to Joan for correctly identifying the caterpillar!

Look for these striking caterpillars in your own gardens, especially if you grow their host plants!