One of our readers found this adorable worm-like organism and sent us a picture:

 

 

So what is this creature? Our reader guessed it could be a tomato hornworm. While this caterpillar does have similar coloring and markings as a tomato hornworm, we think it is actually a spicebush swallowtail caterpillar! We recognize this creature by its light green color, black eyespots, and tan and yellow markings.

Spicebush swallowtails, or Papilo troilus, are common Swallowtail caterpillars and butterflies that belong to the Papilionidae family. There are two subspecies: Papilio troilus troilus and Papilio troilus ilioneus. Spicebush swallowtails are primarily found in the eastern United States and southern Ontario. However, occasionally they show up in the Midwest and even Colorado! The subspecies Papilo troilus  is found almost exclusively in Florida. Like many caterpillars, the name of a spicebush swallowtail is a hint to what it eats. These caterpillars feed on spicebushes, which are deciduous shrubs. They also eat the foliage of prickly ash trees and sassafras trees. While the caterpillars tend to stay put on the leaves they are eating, the butterflies aren’t as stationary. Their flight habits are dependent on nectar and water availability, and possible mates within their region. These butterflies are typically found in deciduous woods or woody swamps with plenty of shade.

Comparing the size caterpillar to our reader’s hand, we believe that this spicebush swallowtail caterpillar is probably almost ready to pupate and mature into a butterfly!

To wrap up, one of our readers sent us a picture of a green worm-like specimen with interesting markings. We are confident that this creature is a spicebush swallowtail caterpillar. Our reader didn’t ask any other additional questions besides the identity, but we have provided some information about the species, its habitat, and feeding tendencies.