title: Phylogenetics of Chinese Dryopteris (Dryopteridaceae) based on the chloroplast rps4-trnS sequence data.
abstract: Dryopteris is one of the largest and most taxonomically complex fern genera in the Dryopteridaceae, with 127 species occurring throughout temperate, sub-temperate, subtropical, and tropical China. Investigations of the evolutionary relationships of a subset of these Chinese Dryopteris species, using DNA sequence-based methods, specifically tested the monophyly of the genus and the validity of the previous subgeneric classifications. Sixty species of Dryopteris, four closely related non-Dryopteris and three species of Arachniodes, were used as outgroup taxa. The rps4-trnS region of the chloroplast genome was sequenced in these species for the first time. Both maximum parsimony (MP) and neighbor-joining (NJ) analyses identified six polyphyletic clades that contained Dryopteris species. These results were supported by a Bayesian analysis of the same data set. The phylogenetic patterns strongly suggest the polyphyletic status of Dryopteris; the monophyletic groupings of the species do not correspond with either Fraser-Jenkins [In: Bull Brit Mus (Nat Hist) Bot 14(3):183-218, 1986} or Wu (In: Flora Reipublica Popularis Sinicae Tomus 5 (1) pp 1-241, 2000] subgeneric classification of Dryopteris, except in a few specific cases. This work represents the first molecular systematic analyses of Chinese Dryopteris, and we propose the next steps necessary to recognize new subgenera of the genus.
authors.affiliation: State Key Laboratory of Palaeobiology and Stratigraphy of the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Science, Nanjing, Jiangsu Province, People's Republic of China. cxli@nigpas.ac.cn
authors.forename: Chun-Xiang
authors.initials: CX
authors.lastname: Li
authors.forename: Shu-Gang
authors.initials: SG
authors.lastname: Lu
mesh_terms: D001483:Base Sequence; D002681:China; D002736:Chloroplasts; D018742:DNA, Chloroplast / Q000235:genetics*; D032492:Dryopteris / Q000145:classification* / Q000235:genetics; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D018742:DNA, Chloroplast; D010940:Plant Proteins; C097421:rps4 protein, plant