I have a small freshwater aquarium at home with only some aquatic plants at the moment. In the summer, I put some mud and sand from a local pond into the tank. At some point, I noticed a strange moving "segment" of plant:

Tiny bug hidden in a "tube"

Here is a video of it moving right under the surface of the water:


If you look closely, you can see that the "segment" is actually made from several smaller segments of a stem of an aquatic plant. In other words, this little creature chopped up the plant, then assembled this little "tube" for itself to hide.

Few weeks later, it apparently disassembled the little house and created a larger one from leaves:

It grew larger and made a leafy house for itself

Here is a video of it:


It basically this little leafy house everywhere and can move up and down the water column. I think it feeds on different plants because I can see some visible damage in the tank.

Can you identify this creature? The location is northern Europe.

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    $\begingroup$ Those videos are great! It's some sort of caddisfly larva, known for the cases they create, but as there are ~14,000 species, I can't begin to say which one. Maybe someone else will know. :) $\endgroup$ Commented Dec 3, 2023 at 20:12
  • $\begingroup$ @anongoodnurse I would be quite content with just knowing the order or family! And yes, I think you are exactly right after reading the wikipedia page :) $\endgroup$
    – Aufheben
    Commented Dec 3, 2023 at 20:16
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    $\begingroup$ in norwegian we call them vårfluelarver(spring fly larvae),one way to identify them is from the materials they use in their "house"different types use different materials,some use grains of sand other ones use dead leaves or as in your picture green parts of plants. $\endgroup$ Commented Dec 4, 2023 at 7:37


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