Molecular Phylogeny and Biogeographic Diversification of Linnaeoideae (Caprifoliaceae s. l.) Disjunctly Distributed in Eurasia, North America and Mexico

摘要: Linnaeoideae is a small subfamily of erect or creeping shrubs to trees in Caprifoliaceae that exhibits wide disjunct distribution Eurasia, North America and Mexico. Most taxa the occur eastern Asia Mexico but monospecific genus Linnaea has circumboreal north temperate distribution. In this study, we conducted phylogenetic biogeographic analyses for its close relatives based on sequences nuclear ribosomal ITS nine plastid (rbcL, trnS-G, matK, trnL-F, ndhA, trnD-psbM, petB-D, trnL-rpl32 trnH-psbA) markers. Our results support monophyletic, consisting four Asian lineages (Abelia, Diabelia, Dipelta Kolkwitzia), Mexican Vesalea, Linnaea. The Vesalea was formerly placed Abelia, it did not form clade with Abelia; instead are sisters. divergence time between plus dated be 50.86 Ma, 95% highest posterior density 42.8 Ma (middle Eocene) 60.19 (early Paleocene) using Bayesian relaxed clock estimation. Reconstructed ancestral areas indicated common ancestor may have been widespread originated during Eocene likely migrated across continents Northern Hemisphere via Atlantic Land Bridges Bering Bridge. Qinling Mountains modern-day center diversity Kolkwitzia-Dipelta-Diabelia clade. Diabeliaclade became highly diversified Japan China. Populations Diabelia serrata China were found genetically identical suggesting recent disjunction East Sea, following last glacial event.