Caugak ukuk?

Well, some of you told me you all liked this, so here's an easier one. It's got a skull, if you want to go based on that, but also, it's got a reeeeeally recognizable skin:
You might have seen these on hats, parkas, and a billion other places, because they've got good skins. Be a little more exact that `rodent!` Also, I'm curious what other names exist for these critters.

If you're paying attention, you'd have noticed the title isn't `Cauga una?` That's because there's two of them, so you have to change the question to reflect this. Cauga goes to caugak, and Una for this goes to ukuk for `these two`.