This one led me a merry chase through “first instar caterpillar”, “bagworm” and even “beetle larva” until finally an article about dermestid beetle larvae turned up a photo of a duff millipede. This is a millipede! Would you believe it?
This extremely tiny (3mm) creature looks, at first glance, like a piece of lint. Getting a little closer, you can see a caterpillar-like beastie, but the distinctive tuft on the end of its abdomen gives it away, as do the starburst-like bristles on its flanks. Because of these “hairs”, these little guys are also called pincushion millipedes. The Latin name is Polyxenus…and y’all will just have to forgive me about the actual species, because literally 3mm long, guys. I need to buy a microscope….
These insects are extremely unique — especially for millipedes — in their soft, unarmored body and the setae, or hairs. They lack the chemical defenses and armored exterior of more traditional millipedes; instead, the individual setae have little barbs or hooks on them, are easily detached, and can become entangled around predatory insects (such as ants), rendering the millipede difficult to eat.
Males deposit a spermatophore on the ground which is subsequently picked up by a female. Alternatively, some species reproduce asexually!
These little guys are pretty hard to find out in nature, but sometimes they do enter human homes looking for humidity. (The ones pictured were on my garage door.) They are mostly blind — some species don’t even have eyes. They eat fungus and decaying matter, and are harmless to humans.