“My son found a few of these on his front porch,” states this reader in Severna Park, Maryland. She is referring to the organisms pictured below, which she thinks are black beetle larvae.”
This identification was based on some browsing our reader had done on our website, where she compared images from past articles to the ones she had taken. What makes our reader uncertain about this identification is “the way the body is covered with debris and just a portion of the rear end”, along with pincers, “is exposed.” As such, she asks that we help her identify the creature.
Given the color of the organism, as well as the “debris” covering its body, we also doubt that this is a black beetle larva. We also doubt that what we are looking at is merely debris. We think it is a case of sorts, and with that in mind, there are indeed species of beetles that make cases, such as the case bearing leaf beetle. However, this creature in particular does not resemble a case bearing leaf beetle larva. To us, this looks more like a Saunders’ case moth caterpillar, minus the typical orange splotches that they tend to have on their otherwise black bodies. We suppose this might be an immature Saunders’ case moth caterpillar.
Alas, we also doubt that it is a Saunders’ case moth caterpillar, but not because its coloration does not match up, but because there are no records of this moth being found in the United States: it is native to Australia. That said, the debris-like cases, which look like they could be made from pieces of moss and/or wood chips, look eerily similar to the ones that Saunders’ case moth caterpillars make. It is not entirely impossible that they have migrated to the United States, accidentally or not, but we will not go so far as to make that presumption.
We also considered that they might be caddisfly larvae, as their cases also look like a patchwork of organic debris. Unfortunately, the organism itself does not look like the one’s our reader’s son found, so we quickly ruled them out.
To conclude, we do not know what these organisms are, though there is a slight chance that they really are Saunders’ case moth caterpillars, or some American variation of them. If any of our other readers have any clues as to what they might be, feel free to share any ideas in the comments section below! In any case, if our reader wants a second opinion, she could take the organisms to her local county extension office. We wish her and her son the best, and thank them for enlightening us with this new creature!