One of our readers found a brown caterpillar in her driveway. At first, she thought it was a twig, but when she picked it up, she realized that it was soft and fluffy. It was about 2.5 inches long and it appears to have big eyes. These eyes that our reader sees are eyespots and once we viewed the pictures that she sent us, we determined that it is the Eastern Tiger Swallowtail caterpillar.

Some time ago, a reader asked us to identify a brown “worm” he found. The creature was brown with a big head, on which there appeared to be two eyes. We placed the word “worm” in quotation marks because the reader did not in fact find a worm, but rather a caterpillar. Of this much we were fairly certain when we first attempted to answer our reader’s question. However, we were unsure exactly what the brown caterpillar was, as in, what precise species of caterpillar our reader came across. Thanks to reader comments, we are now confident that our reader found an Eastern Tiger Swallowtail Caterpillar (Papilio glaucus).

A couple wrote to us about a “worm” they found that might be of interest to their grandchildren. (Actually, they said their “G-Kids,” which we presume to be grandchildren, although GKIDS is also an acronym for a few different things, muddying the situation.) The readers were right to put the word “worm” in quotation marks, as the creature they found is not a worm, but rather a caterpillar. Indeed, we are fairly certain it is a Tiger Swallowtail caterpillar. Below is some basic information about the Tiger Swallowtail caterpillar, along with a nice picture of the caterpillar submitted by the readers.