I happen to have a copy of your protologue for both Spathoglottis palawanensis and S. philippinensis, and would like to ask where exactly do they differ from one another? Looking at the photos supplied on the protologue, the most obvious difference lies in the colouration of the sidelobes- they are heavily masked in red in S. philippinensis while the red is very much reduced in S. palawanensis. From the description, I noted that the measurements given for vegetative and floral parts of both taxon show overlap. Indeed, it would seem that they can be separated only by their flower diameter (4.5 cm for S. palawanensis vs. 3.9 cm for S. philippinensis), the colouration of the sidelobes and provenance (S. palawanensis is from Palawan, while S. philippinensis is from Panay, I believe).
Have there been stable morphological differences observed after their description was published that would make the distinction between the two more clear-cut?