title: A molecular phylogeny of Dichocarpum (Ranunculaceae): Implications for eastern Asian biogeography.
abstract: East Asia is characterized by high levels of species diversity and endemism. However, the biogeographical patterns and processes underlying the distribution of biodiversity within the area are still poorly known. In this study, we used plastid (matK, trnL-F, and trnH-psbA) and nuclear (ITS) DNA sequences to investigate the historical biogeography of Dichocarpum (Ranunculaceae), an eastern Asian endemic genus throughout warm-temperate and subtropical forests of the area. Phylogenetic analyses strongly support Dichocarpum as monophyletic, which contains two major clades. Clade I corresponds to section Hutchinsonia, and clade II includes sections Dichocarpum and Fargesia. Section Dichocarpum and its subsections Dalzielia and Dichocarpum are not recognized as monophyletic. Our results suggest that the most recent common ancestor of Dichocarpum occurred in central China and Japan in the earliest Early Miocene, and thus support an ancient vicariance event between Japan and China. Within mainland China, three migrations at the species level were hypothesized to explain the expansion of Dichocarpum from central China to southeastern Yunnan, Hengduan mountains, and eastern Himalaya. These migration events occurred in the Late Miocene to Early Pliocene, which may be associated with the uplift of the southeastern Qinghai-Tibetan Plateau and accordingly the expansion of subtropical forests in China around that period. A migration or dispersal from central China to Taiwan was inferred in the Early Pleistocene, which supports the close floristic affinity between Taiwan and mainland China. This study contributes to our knowledge on the historical biogeography of plants in eastern Asia.
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Kun-Li
authors.initials: KL
authors.lastname: Xiang
authors.affiliation: College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Central Siberian Botanical Garden of the Siberian Branch of Russian Academy of Sciences, Zolotodolinskaya str. 101, Novosibirsk 630090, Russia; National Research Tomsk State University, Laboratory of Systematics and Phylogeny of Plants, prospekt Lenina 36, Tomsk 634050, Russia.
authors.forename: Andrey S
authors.initials: AS
authors.lastname: Erst
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Sheng-Xiang
authors.initials: SX
authors.lastname: Yu
authors.affiliation: Institut de Systématique, Evolution, Biodiversité, ISYEB - UMR 7205 - CNRS, MNHN, UPMC, EPHE, Muséum national d'Histoire naturelle, Sorbonne Universités, 57 rue Cuvier, CP39, Paris 75005, France.
authors.forename: Florian
authors.initials: F
authors.lastname: Jabbour
authors.affiliation: State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: wangwei1127@ibcas.ac.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
mesh_terms: D005202:Asia, Eastern; D005231:Fatty Acids, Unsaturated / Q000235:genetics; D014644:Genetic Variation; D016013:Likelihood Functions; D010802:Phylogeny; D058974:Phylogeography; D029626:Ranunculaceae / Q000145:classification* / Q000235:genetics*
chemical_list: D005231:Fatty Acids, Unsaturated; C055648:9-(4-chlorophenyl)-7,7-dimethyl-5,8-nonadienoic acid
keywords: Biogeography; Dichocarpum; East Asia; Japan; Phylogeny; Taiwan