This is a division of a plant which was bought from a collector (most likely habitat collected) in Laos many years ago, it was assumed to be Paph. callosum var. thailandense, which it clearly is not... any ideas?
I would say it's P. callosum, perhaps not the common clone but P. callosum.
In my opinion the differences are normal within the variety of a species which natural habitat is such a large or huge area (Thailand/Laos/Malaysia)
The dorsal is more slender than that of the common P. callosum but the stance of the petals is P. callosum, the warts on the petals are P. callosum and last but not least the staminode is genuine P. callosum.
Please compare with mine P. callosum and correct me in case I'm wrong.
I would say that it is the sublaeve form of callosum (which is the same as "thailandense", I believe...) The main thing that is unusual is the lack of warts on the petals...probably something else got into the genetic makeup at some point...barbatum, perhaps? Take care, Eric