Excuse my ignorance, but I'm really curious, if it's a trident like Al stated, why hasn't it dropped it's leaves? Al, thanks for the history on this by the way. I had no idea that tridents even had a different look in their recent ancestry.
I have about 45 tridents in all states of growth. Some that I use for cutting stock and graft stock and thread graft stock is under a thicket of trees on my fence line. It is totally covered by trees and trees started by birds, many privits and stuff like that. There are tridents in there so insulated from the cold as well as having fairly mild winters that tridents will just keep growing year round.
I have to move them out into the yard to get some cold to induce dormancy. I also have a hard time getting really good fall color on my maples because of this. Even the shade cloth is protection enough for me to keep leaves well into January.
The palmatums always lose their leave fairly early though.
It might also be that the tree in question from Brett in not a maple at all. Could be some ivy for all we know. I have not seen it close up enough.