A multivariate analysis of Cymopterus glomeratus, formerly known as C. acaulis (apiaceae)

Five infraspecific taxa have been recognized in Cymopterus glomeratus (= C. acaulis): vars. glomeratus (= acaulis), fendleri, greeleyorum, higginsii, and parvus. The results of previous phylogenetic analyses of DNA sequence and morphological data have supported the close association of these five varieties, although the relationships among them could not be discerned. The recognition of infraspecific taxa within C. glomeratus is controversial. Multivariate analysis of variance and principal component analysis of 288 specimens representing the morphological variability and geographic distribution of this species complex were conducted to test the validity of these infraspecific taxa. Results show that most of the characters previously used to recognize these varieties are highly variable within the taxa. Although analysis of variance demonstrated some statistical differences among the varieties, patterns were not consistent. No clearly separated clusters are revealed in the principal component analysis and all five varieties were intermixed on the plots of the principal components. On the basis of the results of both phylogenetic and multivariate analyses, we propose that plants in this species complex be recognized as one species, C. glomeratus, with no varieties. The nomenclature and typification of this species are presented.