The funny thing is that Braem himself (Genus Paphiopedilum, 2nd ed.) in his text only reckons one colour form of tonsum apart from the typical one, namely fma. alboviride. Almost needless to say, that he has P. braemii as a separate species.
In the illustrations to the chapter, though, where these species are described, there suddenly appears a photo of P. tonsum 'curtisipholium'. How this has to be interpreted remains something of a mystery to this reader? Maybe, he just couldn't make up his mind about its taxonomic status?
Braem's flower has a more distinct greenish hue to it's dorsal and petals than bulolo's has (maybe just because photos taken with a very different light?) - and in that respect looks like an intermediary form between the typical tonsum and braemii.
Maybe, it makes more sense to consider them all within the range of the same species (possibly with braemii and maybe also curtisipholium as varieties).
There seems to be room for a revision of the P. tonsum complex - and the opportunity for publication for botanists! (Do you hear me, Olaf?
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