J Syst Evol ›› 2020, Vol. 58 ›› Issue (5): 696-709.DOI: 10.1111/jse.12597

• Research Articles • Previous Articles     Next Articles

Taxonomy and biogeography of Diapensia (Diapensiaceae) based on chloroplast genome data

Jian-Fei Ye1,2†, Yan-Ting Niu1†, Yan-Lei Feng3, Bing Liu1,4, Li-Si Hai1,5, Jun Wen6, and Zhi-Duan Chen1,4*   

  1. 1State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2Beijing Botanical Garden, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    3Institute for Evolution and Biodiversity, University of Muenster, Muenster 48149, Germany
    4Sino‐Africa Joint Research Center, Chinese Academy of Sciences, Wuhan 430074, China
    5University of Chinese Academy of Sciences, Beijing 100049, China
    6Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013‐7012, USA
  • Received:2020-03-12 Accepted:2020-04-29 Online:2020-05-07 Published:2020-09-01


Diapensia L. is the second largest genus of Diapensiaceae. The taxonomic treatment within Diapensia and relationships within Diapensiaceae have been disputed. Chloroplast genome sequence data have proved to be useful for plant phylogenetic analyses and species delimitation. In this study, we de novo sequenced and assembled 22 chloroplast genomes of 15 species of Diapensiaceae, including all recognized species of Diapensia with multiple samples. A super‐matrix containing a total of 107 genes and 18 taxa was constructed for phylogenetic analyses to resolve phylogenetic relationships among genera of the family and within Diapensia. The resulting phylogenetic tree showed the following strongly supported relationships: (Galax, (Pyxidanthera, (Berneuxia, ((Schizocodon, Diapensia), and Shortia s.s.)))). The dated phylogeny and reconstructed lineage‐through‐time plot for the family indicated rapid diversification in the Neogene and an acceleration of diversification rate after c. 8 Ma. Biogeographic analysis suggested that Diapensia originated in the Northeast Asian mountains approximately 6.06 Ma, followed by northward dispersal to the Arctic and southwestward dispersal to the Himalaya–Hengduan Mountains. Phylogenetic relationships within Diapensia were well resolved. Based on the phylogenetic results, we proposed to reinstate the species status of Diapensia bulleyana Forrest ex Diels, and raised D. purpurea f. albida to the species rank (D. albida [W. E. Evans] J. F. Ye comb. & stat. nov.). The distribution ranges of all species delineated based on the phylogenetic results were revised accordingly based on specimen occurrences. Our study adds new examples for the power of plastid genome data for resolving phylogenetic relationships and clarifying taxonomic disputes among closely related species.

Key words: biogeographic disjunction, chloroplast genome, Diapensia, Diapensiaceae, phylogeny, taxonomic treatment