A “little critter” was found on this reader’s driveway last summer in her small North Texas town. The critter appears to be a bright green color and has a brown face, split down the middle by what we assume to be access to its mouth.
Our reader elaborated by saying that she posted photos on her town’s website but had no luck in getting the creature identified. She has also done internet searches but still found nothing and hopes that we can tell her what it is. From the bright green color, to the segmentation one can just make out from the photo, this critter is quite clearly a Polyphemus moth caterpillar.
The Polyphemus moth is a silk moth, and one of the largest ones at that. It is also considered one of the most beautiful, the adult form sporting brown wings of various shades, with red lines and yellow spots that look like eyes making a symmetrical pattern that is admittedly pleasing to the eye. Speaking of eyes, it is the ‘eye spots’ on its wings that gives this moth its name, Polyphemus being a one-eyed cyclops in the mythologies of ancient Greece. When young, the larvae of the Polyphemus moth are black and white-striped, with orange bulbs that sprout bristles and a red head. They only grown up to 6mm in length. Yet, once the caterpillar is fully grown and ready for pupation, it is a solid green color, with a brown head and grows up to 75mm. In the in-between stages, the caterpillar will be somewhere between 14-45mm and a yellow-green color. Given the color of the caterpillar in the photograph our reader sent in, we would assume it is somewhere in the its middle stages.
Polyphemus moth caterpillars, like most caterpillars, feed on the leaves of various plants. At times, they will even chew off the stems of leaves to drop them to the ground before eating them. Additionally, they also eat the egg that they hatch from. These caterpillars are not venomous, nor are they known to carry parasites, so our reader has nothing to worry about in terms of her health. Of course, just like with any creature, we still advise caution if handling the caterpillar. One can still potentially experience an allergic reaction when making skin-to-skin contact with a caterpillar, so we advise wearing gardening gloves or some other form of protective measure if the caterpillar needs to be moved. Otherwise, we recommend simply leaving it alone. Then again, these caterpillars can be considered pests, especially in California, where they are considered pests of commercial plums. So, if one wishes to rid their garden of these caterpillars, simply moving them to a forest or park where they can feed on other plants should help control the problem to a certain extent.
To conclude, the little critter our reader found on her driveway last summer is a Polyphemus moth caterpillar. Our reader should count herself lucky to have found such a beautiful specimen, and we hope that our article was able to enlighten her and provide some useful information.