I never read anything about bugs on aquatic plants, but my new Ludwigia Narrow leaf has them. They are little 1/4" clear worms that take 2 circular pieces of leaves and make a sandwich of themselves in the middle. Then, they run around eating my poor Ludwigia to pieces -- I was falsely accusing snails. I kept seeing these leaf pieces and didn't think much of them. Today I was watching and said, "Hey, that thing is moving!" Pulled it up and there was a worm in the middle.

I have 4 Ludwigia and they are only on the one as far as I can tell. I'm thinking to pull the thing and clean it off well.

If anyone has any experience with these critters, please let me know what I should do. I'm hoping that the adults will not be able to breed.

I just pulled the plant and am going to toss it -- there were lots of these caterpillars/worms. My tank actually looks better since it opened up some space. I wouldn't be surprised if these bugs spread to my other 3 Ludwigias -- I'll probably just pull them all at that point. The Ludwigias are beautiful at their tops and from above, but all those roots down below were not overly attractive to me anyway.