What are those #(*@ little bugs that mysteriously appear in tightly closed containers of rice,pasta,flour.?

I can only say that in my experience I often find them in flour and even rice. Once they are in those for a long enough period of time, they can migrate into other items in your dry storage. Those little mites often are eggs unseen in the mills where your food is packaged. I can't say whether or not its dangerous to consume them, very unappetizing for sure. I have been advised to put these items like flour into my fridge or freezer to eliminate this problem. If theyre into a lot more of your items, I would guess you might want to toss them and start fresh.