“I am finding a ton of these tiny worms in my bathroom”, writes this reader in her submission regarding the tiny, dark brown critter pictured below. “I vacuumed and sprayed some pest spray, but within two days they’re back in full force (close to 100 worms will cluster up within a week). I’ve done this at least four times. I RARELY see them move. It’s like they show up and 90% are immediately dead? At first I thought it was drain fly larvae, but we’ve never seen a single drain fly. After seeing your articles on CARPET beetles, I’m noticing it looks identical, but it’s weird that it’s only by our toilet! We struggled last fall with cigarette beetles, but now I’m wondering if they were carpet beetles. Again, the beetles were only in the bathroom (but in the shower, not by the toilet). Help! Here are photos of the worms!”

To begin with, we just want to acknowledge that we understand our reader’s frustration at the situation, and her desperation to get rid of this infestation. Infestations can be hard enough to get rid of as it is, but carpet beetle larvae infestations are notoriously difficult. And our reader is correct in saying that these really do look like carpet beetle larvae. She is equally correct in stating that the location of their discovery is odd. For context, carpet beetle larvae feed on the organic fibers in soft materials like clothing, bed sheets, upholstery, and, of course, carpets. For that reason, they are typically found in closets, living rooms, and bedrooms. And while they can also be found in the bathroom, munching on towels or hair, that is likely the least popular room in the home among carpet beetles. It is particularly odd that these are found around the toilet.

Our question to our reader is if she has a bathmat or toilet mat right by the toilet, as this could be what the carpet beetle larvae are munching on. With that said, carpet beetle larvae do look very similar to duff millipedes, and the two species are often confused for one another: we have even made that mistake before. There are key differences between the two species, physically speaking, that one would be able to see upon closer inspection, but unfortunately the photos our reader sent in do not have the best resolution, meaning that when we zoom in on the creature, the photo gets blurry. It would make some sense for these to be duff millipedes, as they feed on fungi, algae, and decaying organic matter, making the bathroom a hotspot for these critters. That said, they do not invade homes nearly as often as carpet beetles, as they can find all of that in a forest, which is where they prefer to live.

Now, our reader is also correct in how she tried to eliminate the infestation. Vacuuming and sanitising are essential in eliminating and preventing insect infestations. Given how many worms are showing up at a time after cleaning, we have to assume that several clusters of eggs are hatching at a time. Since our reader is finding all of them in the bathroom, we assume this is the source of the infestation, meaning the eggs are being laid there. It is possible that the eggs are somewhere our reader cannot easily reach and clean (like behind the toilet, or underneath a cupboard), or somewhere she would not think to clean (like the walls or ceiling). We suggest checking these spots and cleaning them. She might also want to clean her drains, just in case they are coming from there as well. Equally, if the larvae are being found near or on a bathmat or toilet mat, then our reader will want to launder that mat. Similarly, it might be a good idea to launder any towels in the bathroom as well.

To conclude, we are not entirely sure what these creatures are, though they bear a striking resemblance to carpet beetle larvae. They could very well be carpet beetle larvae, though it is possible they are duff millipedes instead. We hope this helps, and we wish our reader the very best!

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