I bought these from Orchid Inn as seedlings of P. superbiens. Could you please direct me to the most recent literature that recognizes curtisii as a valid species. Kew lists curtisii as a synonym and elsewhere I have seen it listed as a variety of superbiens.
No not really. I am fine with calling these curtisii, but in the past I was told that no they are superbiens. If there is settled nomenclature for these plants could someone please direct me to the publication?
There isn't! And I'm not the one to open the whole can of worms, that Eric is hinting at!
Just point to the fact, that the botanical descriptions of both species, respective varieties (if in the camp of 'lumpers'), and the distinctions between the two, generally leave a lot to be desired - and more often than not contribute to confusion and bewilderment.
The only distinction that makes any sense to me is between the rediscovered 'true' superbiens and all the curtisii's - see this post by Olaf Gruß:
Your plant is really a true Paphiopedilum curtisii. Some years ago the true Paph. superbiens was found again and this Shows the clear differences to curtisii. Her eat first two different clones of curtisii