What a name, huh? Anyway, I bought a copy of this recently; the tag just noted chumpornensis. I did a bunch of research and found it to be Dor. pulcherrima v. chumpornenses. In my Google search I even found (on Garden Banter) a dialogue between Ray and Al in which Ray refered to the plant using v. chumpornensis. Al, by the way, was in top form. ;o)
But I did find one odd reference claiming that chumpornensis is a trade name. Any more info on this than what I've found? The photos I came across match the flower perfectly.
TX Diana