How to delete (or refine or whatever) extra bones poped up from nowhere?

Hello everyone.

I have an animation, that is fine with the other models. But a model that I am working on,
in some certain parts, there is some tiny bones pop up from nowhere, and ruin my model’s pose when it is animating.

Please look at the gif in this link
https://drive.google.com/open?id=1K0GxHOj4_MIsFkpVMSCxxDF_EwfaVUGE

Thank you.

It’s not likely that those bones are just popping up from no where. They’ve been in your rig the whole time. You just need to find them. You should be able to select them in Pose mode and then switch to Edit mode. They should still be selected and you can better figure out where they are in your rig. Also, I’m assuming that you haven’t named all of your bones. I highly recommend you do that. It helps you track down things like this much more easily.

Yes you are right. They are at the tip of the toes. I tried to delete it but doing that makes thing even worse. This rig set never has a problem with every motions that I have been working,

Can you please take a look at it? The “popping up” occurs at frame #1600
https://drive.google.com/open?id=1iDOhalpJApug8WdINUYu8Ggoh7bBFDza