From Folk Taxonomy to Species Confirmation of Acorus (Acoraceae): Evidences Based on Phylogenetic and Metabolomic Analyses.

Plants inAcorushave been used as herbal medicine by various linguistic groups for thousands of years. Arguments of taxonomy ofAcorusamong scientists resulted in confusions and misuses ofAcorusplants. The present study used different methods to investigate the classification of the genus, based on folk taxonomy. The relationships amongAcorusspecies were revealed through phylogenetic analyses by constructing the Maximum Likelihood and Bayesian phylogenetic analyses based on sequences of two chloroplast regions (trnL-trnFandrbcL). All samples named with two so-called synonyms,Acorus macrospadiceus(Yamam.) F. N. Wei and Y. K. Li andAcorus tatarinowiiSchott collected from different habitats, were clustered into separate groups, which revealed that they represented two independent species. Multivariate statistical analysis of metabolites from differentAcoruspopulations were carried out based on UPLC-QTOF-MS data. Three independent analysis, principal component analysis, heat-map analysis, and hierarchical cluster analysis, showed thatA. macrospadiceusandA. tatarinowiiare different from two recognized species in the genus,A. calamusL. andA. gramineusAiton. The results of phylogenetics and chemotaxonomy, together with morphological and ecological evidences, were consistent with traditional knowledge of local people related toAcorustaxa, which proved the significance of parataxonomy. Multiple evidences including morphological, ecological, folk taxonomic, phylogenetic, and chemical taxonomic results suggested that there are four species in the genusAcorus.