Differs from P. esquirolii in the smooth upper leaf surface, deeper flower color, oblong flower lobes and style usually extending beyond the anthers. Differs from P. coerulea in its homostylous flowers, and in the whole plant usually covered with sparse glands. This species is rare amongst the section Petiolares in having homostylous flowers (only P. hookeri, P. chamaethauma and P. esquirolii share this character). Only found at the type locality on Gaofeng mountain in Pingba, Guizhou.