Looks like a revolution cut variation
There isn't a specific name?
I'm on the go right now, but this video may have your answers and then some:
It's the Knuckle Cut
May i ask why you're so curious on finding the name of this cut?It's not the knuckle cut. I'm using my thumb, not my knuckle. Also I'm holding the deck in between my index and middle fingers. I've been looking through youtube to find it..but I haven't yet. My father taught me it a long time ago, which he learned from his father..
I'm pretty sure somewhere out there - someone else does it; and know's what it's called.