Actually, there's nothing rare about it at all. It's just a winged elm (Ulmus alata) -- also known as a corked or wahoo elm -- and they are everywhere in this part of the world. But, this is one I have walked by for years on our relatively regular strolls along the Governor's Rail Trail in Edgefield.
Today I noticed it, so to me it's a find. And, none of the several in our yard display wings as full or as colorful as this one, so in that regard to me it's rare.
I'm crazy about it and look forward to watching its flowers bloom and leaves form in the next few weeks.