A reader recently reached out to us because she needs help identifying a worm-like organism she found on her top bed sheet. She doesn’t know how it ended up on her bed. She does have a dog, so the worm could have come from him. She explained that the dog does not go on the bed, but does occasionally sleep in the bedroom. Here is the photo she shared with us:
She mentioned that the creature in question is about 1/2 inch long, and she only found one. From the photo we can see that the specimen is brown and resembles a stick or twig due to its rough texture. What is this mysterious worm-like organism?
We believe this is a stick caterpillar! Stick caterpillars are the larvae of Geometridae moths. There are over 300 species of Geometridae moth caterpillars. These caterpillars have legs on their anterior and posterior ends, but none in the middle. They move by clasping with their front legs and moving their back legs forward, creating a loop with their bodies. Next, they clasp with their back legs, and reach their front legs forward to clasp on to something new, flattening out their bodies. The unique way the larvae move forward is how they get many of their nicknames, such as inchworms and loopers. Stick caterpillars are usually thin, long, and black or brown. Their bodies also have warts, knots, and bumps which add to their stick-like appearance.
We don’t know how or why this caterpillar ended up in our reader’s bed. The dog might have accidentally transported it into the bed, or it could have crawled in through an open door or window. Since she only found one of these larvae and isn’t dealing with an infestation, we encourage her to simply place it outside.
In conclusion, one of our readers discovered a brown worm in her bed. We believe this organism is a stick caterpillar, but we aren’t sure how it ended up in her bed!