Orange and Yellow Worms in the House

Some time ago, a reader wrote to us about orange and yellow worms she has been finding in her house. The yellow and orange worms (the worm is actually “yellowish,” in the reader’s words, and we suppose this means it is not fully orange, but rather orangish) are coming from a corner of the house, and she is finding them on her ceiling. The reader is wondering not only what the worms are, but also if they are dangerous. Perhaps in part because of the latter concern, she is also curious how she can get rid of them. So, in short, what are these yellow and orange worms, are they harmful, and how can our reader get rid of them? Can her orange-and-yellow-worm problem be solved?

Unfortunately, the information contained in the paragraph above is all we were given. We have no idea where the reader lives, so we don’t know the habitat of the creature in question. We also have no idea how big it is, or if it has any distinguishing characteristics. Finally, we weren’t sent a picture. (Obviously, we can’t spontaneously identify a creature in every photo we see, but it’s helpful to have one to check against our research or initial hypotheses.) All of this leads us to state the obvious: we don’t have anywhere close to enough information to precisely identify what our reader found; consequently, we also can’t say if what she found is harmful, nor can we recommend any specific methods for eliminating the worm intrusion. We can, however, speak in more general terms, and in so doing we hope to aid our reader in some way.

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First, we have been using the word “worm” so far (because this is what our reader asked about), but given the creature’s vibrant appearance (or so we imagine based on its coloring), we think there is a fairly good chance our reader is actually dealing with some type of caterpillar – not a worm. She might have found larvae, but we don’t know of any orange larvae that you might find inside. (There is a larva called the “navel orangeworm” that is a reddish, orangish color early in the larval stage of its life cycle, but this is a pest of almonds, so we don’t know why or how it could be at our reader’s home, unless she is growing almonds.) She also might have found an orange/yellow millipede or centipede (there are examples of both), but this would be strange in that she didn’t mention that the creature has tons of legs. It’s also technically possible she found the amphibian known by the scientific name Schistometopum thomense, but this is only possible if our reader lives on one of a few small islands in the Gulf of Guinea. So, again, we think there is a good chance she found a caterpillar.

As far as what type of caterpillar she might have found goes, we are profoundly unsure, as is to be expected. There are tens of thousands of different species of caterpillars in the world, and many of them are orange and yellow. Some caterpillars are more common than others, so we suppose she probably found a common species, but that’s obviously not very helpful.

Is the caterpillar our reader found (if she even found one) dangerous? Naturally, we can’t answer this question with any measure of certainty either, but we can say that generally caterpillars are not dangerous to humans or pets. (They can be very damaging to plants, however.) When touched they can sometimes cause skin irritation, and some caterpillars emit a foul-smelling liquid, but that’s about all (again, generally speaking). Even if they aren’t harmful, our reader probably still wants to keep them out of her house, and the best advice we can give her is extremely straightforward: she should try to better seal up her house. Often, this is very hard to do because it’s not clear where cracks or gaps in a house might be, but the reader mentioned that the creatures she keeps finding are coming from a particular corner, so she should definitely address that corner first. If caterpillars or other creatures can’t get into her house, our reader won’t find them there.

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We wish we were in a position to provide more information to our reader, but there is simply too much uncertainty surrounding her question. However, we think our reader probably found a caterpillar, and in general caterpillars aren’t dangerous. One thing she can do to keep them out of her house is to merely seal up any space through which they might be squeezing. If any reader has encountered a similar problem and can impart any advice, please do so below in the comments section.

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