A reader recently sent us a short message, a photograph, and the classic question, “What is this?” In his message he explained that he found a dead worm-like organism on the new wood floor in his living room. He also told us that he occasionally finds these specimens in his finished basement by his laundry room. This is the photograph he shared:

This is a great photo! The placement of the penny is a fantastic way to display the small size of this creature. In addition, it is in focus and close up, so we can see plenty of detail despite its small size! The creature is dark brown, segmented, and has tiny legs. This is a millipede!

Millipedes are often mistaken for worms, but they are actually arthropods belonging to the class Diplopoda, along with centipedes. Some people find it hard to distinguish between centipedes and millipedes since both have segmented bodies lined with legs. However, millipedes have two pairs of jointed legs per body segment and centipedes just have one pair! Millipedes also curl up into a C-shape and remain motionless as a defense mechanism, like the one in the photo is doing. So this millipede might not be dead at all, but just playing possum, so to speak.

Millipedes typically prefer a dark and damp outdoor environment. They are abundant in leaf litter on forest floors, and under piles of debris in yards. Since our reader has only found a few of these arthropods inside his home, we think they probably wandered in through a vent, open window or door, or small crack. He can place the ones he discovers outside, and focus on closing off potential entry points. If he continues to find millipedes in his basement or living room, he can also consider installing a dehumidifier, which will eliminate some of the moisture and make the area less hospitable to these arthropods.

To summarize, a reader discovered a small, brown worm-like organism in his living room. We are confident that the organism is a millipede.

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