What is this checkmate called?

It seems a little different than a regular dovetail though

Yeah I don't know

You don't need a name for every checkmate. There are tons of checkmates that have never been named.

i agree

Nice first time I saw this mate 

@hotcrystal1 I said something similar.

It would be the dovetail if a white piece is on b1 on your 3x3 board

According to the Chessable Checkmate course, this is a "triangle mate" as the queen, king and rook form a triangle.

I don´t know. The following checkmates are in the checkmate patterns manual:

Anastasia's mate, Greco's mate, Arabian mate, Hook mate, Vuković's mate, Smothered mate, Suffocation mate, Corner mate, Morphy's mate, Pillsbury's mate, Opera mate, Mayet's mate, Lolli's mate, Damiano's mate, Max Lange's mate, Dovetail mate, Cozio's mate, Swallow's tail mate, Guéridon mate, David & Goliath mate, Boden's mate, Balestra mate, Double knights mate, Double bishops mate, Blackburne's mate, Blind swine mate, Epaulette mate, Back rank mate, Lawnmower mate, Triangle mate, Kill box mate.

Some of these mate´s are known by other names (such as The Kiss of Death as someone mentioned earlier).

Thank you so much!

This is a kill box mate.

Kill Box mate:

Triangle mate:

Very slighty different but essentially the same.

betraying pawn mate??

Already been said. I think it can go in more than 1 category.

cool

how in the world did u find that out