Something’s in my shichimi

So, yesterday, I was enjoying a meal, and adding a bit of spice via my shichimi, as you do, when I got a clump of the stuff that wouldn't pour out. On closer inspection, there was what I would say, a "strand" or "string" attaching a bunch of it together. I opened the tin and found more of these strands.

My wife, alarmed, tossed it before I could take a picture, but I wonder if Japan life might have some idea as to what made these strings. I suspect a spider, but my wife suspects a moth larva. Which of us is right? Or are we both wrong?

Thank you!

by WorldRov3r