P.brevistyla, P.delavayi and P.leptophylla. belong to Celastraceae, ParnassiaL.,Sect.NectarotrilobosDrude,Subsect.Xiphosandra (Franch.) Ku. Due to lack of material, the reliability of their taxonomic characteristics remained unknown and all three species have been retained. Following extensive field investigations, population sampling and examination of specimens, we determined that the previously used characteristics to distinguish these three species, i.e. the shape of basal leaves and the depth of staminode lobes, vary continuously within populations and should not be used to distinguish separate species. Therefore, P.brevistyla and P.leptophylla are hereby designated as synonyms of P.delavayi.
Keywords: Celastraceae; Subsect. Xiphosandra; new synonym; taxonomy.