What's this mate called? I've blundered and had this played on me before. Is there a specific name for the mate?

[FEN "8/8/8/8/1n6/8/qPP5/1KR5 w - - 0 1"]
It does not have any special name. I have been playing for 40 years, and I have never seen it given any specific name.

Here is a very good list of named mates, and as you can see, your position is not among them.