We have these in the inside and outside of our house. I always wondered what they were. I would sometimes watch the wormy guy doing his thing, crawling up the wall dragging his pod-house behind him. He would sometimes pop into his house from one end and pop out the other end! Whatda? This particular guy was in our bathroom the other day, and I finally grabbed my camera and took several pictures. I did a Google image search . . . did you know you can do that? I think it's so cool. And now I know what Pod Guy is. He's a moth in its caterpillar/larva stage!! Howzdat, hah?! The common name is Household Casebearer. The scientific name isPhereoeca uterella.
The case is constructed by the earliest larval stage (1st instar) before it hatches, and is enlarged by each successive instar. In constructing the case, the larva secretes silk to build an arch attached at both ends to the substrate. Very small particles of sand, soil, iron rust, insect droppings, arthropod remains, hairs and other fibers are added on the outside. The inside of the arch is lined exclusively by silk, and is gradually extended to form a tunnel, while the larva stays inside. The tunnel is closed beneath by the larva to form a tube free from the substrate, and open at both ends. After the first case is completed, the larva starts moving around, pulling its case behind. With each molt, the larva enlarges its case. Later cases are flattened and widest in the middle, allowing the larva to turn around inside. A fully developed larva has a case 8 to 14 mm long and 3 to 5 mm wide.