A reader wrote to us recently about worms he found in his shower. The worms are really thin and are of a reddish hue, and they are about two inches long, more or less. With these characteristics taken together, the reader reports that these worms look like particularly small and thin earthworms, just like the ones you see outside after it rains. What are these worms?

Unfortunately, these worms could be a number of different things, some of which aren’t even worms at all. Below we have listed a few possibilities:

To help describe the worms, the reader actually pointed to a previous article on All About Worms that describes small worms you might find in your bathroom, so let’s list these first, just in case these are in fact the creatures that our reader found. The first is the larvae of moth flies, which are often found around drains, including shower drains. Although often found in the area described by the reader, these larvae tend to be very small (less than a forth of an inch in length), and thus considerably smaller than the reader’s worms. Moth fly larvae also tend to be a dark grayish color, not red. The other “worms” covered in this article are carpet beetle larvae. These larvae can be found all over one’s house, including the shower. Again, though, carpet beetle larvae don’t precisely meet the description found in our reader’s question, as these larvae tend to be a brownish color with pale strips along their bodies.

While we’re on the topic of larvae, we should mention the midge fly larvae (often called “blood worms”), 2000 species of which can be found all over North America in aquatic settings. For the most part, people report seeing midge fly larvae in pools, but presumably they could be found in a shower, especially if there is stagnant water accumulated. Midge fly larvae are often red, but they don’t grow to over half an inch in length. So, alas, these larvae also don’t perfectly match the worms (or whatever the case may be) that our reader is confronting. However, given the prevalence of blood worms, they are definitely worth considering.

The reader should consider two additional possibilities: pinworms and horsehair worms. Pinworms afflict humans, causing irritation around the lower intestine and anus area, where they can be observed with the naked eye. During a shower, an infected person might be able to scrub a few of these pinworms off, which would explain why they are in the shower. Like all the other creatures described, though, pinworms are very small, usually under a half of an inch (they also tend to be white), but they are very thin. Horsehair worms, which infect certain types of insects and are found in water, are also extremely thin. However, these worms don’t match the reader’s description for the opposite reason that all the others don’t: they are often considerably longer than two inches; in fact, they can grow to be as long as a foot. Horsehair worms come in several different colors, ranging from an off-white to black.

Regrettably, all of the worms described above are imperfect matches to our reader’s question. On the other hand, all of the worms (and larvae) listed above seem to be the prime candidates, so we would encourage our reader to closely research each to see if one of them actually matches up with the worms that he is observing.