Revision of the genus Gentian L. (Gentianaceae) in Taiwan

Based on intensive morphological study of the genus Gentian from Taiwan, eleven species and two varieties are recognized. All but G. davidii var. formosana T. N. Ho are endemic to Taiwan. Two new species (G. kaohsiungensis C. H. Chen and J. C. Wang and G. tarokoensis C. H. Chen and J. C. Wang) and one new variety (G. flavomaculata var. yuanyanghuensis C. H. Chen and J. C. Wang) are published in this paper. Gentian taiwanica T. N. Ho (= G. angusta (Masamune) Liu and Kuo) and G. kaoi Shimizu are reduced to the synonym of G. scabrida Hayata and G. tentyoensis Masamune, respectively. Gentian loureirii (G. Don) Grisebach, G. manshurica Kitagawa, and G. yakushimensis Makino are treated as excluded species. Calyx-lobe shape and corolla color are the most useful characters for classification of Taiwanese species. A key to the taxa, description, taxonomic character, geographical distribution, classification notes, and specimens examined are provided for each taxon.