Yeh, they are. I can't imagine what would make that or why. Some moths (mentioned in the article) make some structures which are vaguely similar but still not nearly as detailed.
Also there's a clear cocoon at the center of the moth ring, but it's not clear what's at the center of the "maypole" in the other structure. Or if there's anything in there. Someone needs to take one of those things apart under a microscope and see what's in there.