A taxonomic study of Camellia brevistyla and c. tenuiflora (Theaceae) based on phenetic analyses

Camellia brevistyla and C. tenuiflora, two ecologically and economically important species of Taiwan, have long been confused due to their morphological similarities. This paper aims to clarify their taxonomic relationship based on phenetic analyses of morphological data. We characterized the patterns of morphological variations of C. brevistyla and C. tenuiflora, along with C. hengchunensis and C. kissi, throughout their geographic ranges in Taiwan. The ordination plots obtained from non-linear principal analyses showed considerable overlap among the samples of C. brevistyla and C. tenuiflora, and none of the characters applied was able to distinguish the two species apart. Further assessment of morphological characters revealed considerable morphological variations across the entire geographic range. Pearson's correlation coefficients for the data suggested the occurrence of a continuum of morphological variation among the C. brevistyla-C. tenuiflora complex. It is concluded that C. brevistyla and C. tenuiflora belong to a single highly-variable species and the taxonomic treatment of C. tenuiflora as a synonym of C. brevistyla is supported.