“While sitting on the couch, I noticed there was something very tiny and dark moving on my arm”, writes Catherine in her submission, which unfortunately does not include a photo. “About the length of an eyelash and not much thicker. I could distinguish a small head and it was moving around like a caterpillar. The more prominent head and movement makes me think of a larva. After hours of internet searching, the closest comparison I found was that it looks like a dark, micro-sized moth larva. After finding the one, I noticed three more on my other arm. That’s when I ran for the shower. I shook my hair over the sink and nothing. I did find a dead one on the shower wall after rinsing myself.

“A bit about what I was exposed to a short time before: I was around a horse and some hay. This is a daily thing but just in case, I checked what a horse or hay could transmit. Found nothing. There are many plants in my home and there are tiny little flies that hang around them. I could not locate any obvious ‘nests’ and these plants have been in the home for many years. It was also very windy, maybe something from a tree flew on me. This is the first time I see these things after being exposed to all of the above on a daily basis. I’m at a complete loss and am hoping for leads about these things. I apologize for not including a picture as I was more concerned about killing these things crawling on me. If I do find another, I will be sure to be calm enough and take a picture to submit it to you. Anything you can think of, please let me know. Thank you so much!”

Seeing as Catherine did not include any photos, we will not be able to identify the organisms she refers to with complete certainty or accuracy. That said, we do think it is possible that she is finding larvae of some sort: her description of their physical appearance would corroborate that conclusion. Caterpillars can enter the home in a variety of ways, some of which Catherine has already pointed out. There’s no way for us to pinpoint exactly how it happened, but we can definitely suggest some ways of preventing such critters from entering the home. Installing window screens is vital, as is ensuring their upkeep; any torn window screens should be mended or replaced, otherwise they become futile. Similarly, putting screens in vents can also prevent critters from getting in that way, as can sealing cracks in walls and floors. On top of that, removing piles or organic debris from one’s yard is helpful in keeping worm-like creatures from approaching your house, as they tend to take shelter in piles of rocks, twigs, and leaves.

What Catherine can also do is scan her home for any more larvae, and try to locate the source: this will be where there is a high concentration of the larvae. If they are somewhere where there are a lot of textiles (like on the couch, or in her closet), then they are likely clothes-eating pests like carpet beetle larvae or webbing clothes moth caterpillars. She will want to launder any infested textiles (and textiles near the infested ones) and vacuum her home. If the larvae are on her plants, we recommend isolating infested plants and repotting them, all the while hand-picking larvae and moving them outside. Catherine mentions finding a dead one on the shower wall after she showered, but that one likely ended up there because it was on her arm as she mentioned. She also mentions flies, and these could very well be fly larvae. If they are, there will likely be a lot of them hanging around the kitchen or any compost bins. If this is the case, toss any infested foods, and make sure all kinds of foods are stored properly, and that the kitchen is kept clean of food debris.

To conclude, we cannot say for certain what Catherine found since she did not send in any pictures. If she wants to know exactly what species they are, we recommend she sends us pictures of them, or that she takes them to her local county extension office. In any case, it sounds like they are some kind of insect larvae. We wish Catherine the very best.