J Syst Evol ›› 2025, Vol. 63 ›› Issue (2): 401-415.DOI: 10.1111/jse.13124  cstr: 32099.14.jse.13124

• Research Article • Previous Articles     Next Articles

Phylogenetic reconstruction of Didymocarpus and related genera in Gesneriaceae with establishment of two new genera

Fang‐Pu Liu1,2,3, Meng‐Qi Han1,2,3, Peng‐Wei Li4, and Yin‐Zheng Wang1,2,3*   

  1. 1State Key Laboratory of Plant Diversity and Specialty Crops, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2China National Botanical Garden, Beijing 100093, China
    3College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
    4Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain, Guangxi Institute of Botany, Guangxi Zhuang Autonomous Region and Chinese Academy of Sciences, Guilin 541006, China

    *Author for correspondence. E‐mail: wangyz@ibcas.ac.cn
  • Received:2024-05-08 Accepted:2024-06-19 Online:2024-09-29 Published:2025-03-01
  • Supported by:
    This work was financially supported by funding from the National Natural Science Foundation of China (Grant Nos. 31970239, 32170228, and 31530003).

Abstract: The genus Didymocarpus Wall. is a core group of the subfamily Didymocarpoideae in Gesneriaceae with a complex taxonomic history. It has long been controversial to delimit Didymocarpus and its allies. We conducted phylogenetic reconstructions with high-density sampling of Didymocarpus and related genera by using four nuclear ribosomal DNAs (external transcribed spacer [ETS], internal transcribed spacer [ITS], 18S, 26S) and five chloroplast DNAs (atpB-rbcL, rpl16, rps16, trnH-psbA, and trnL-F). The results indicated that neither Didymocarpus nor Allocheilos are monophyletic. Based on molecular phylogenetic and morphological analyses, we delimitated the range of the Didymocarpus sensu stricto (s. str.) with two-section division, and established a new genus Palmatiboea for species originally placed in Didymocarpus. This genus is remarkably distinguished from Didymocarpus s. str. not only in molecular phylogeny and morphology but also in its specific geographic distribution, in that it is found only in Southeast China. In addition, we proposed a new monotypic genus Hequnia for Allocheilos guangxiensis that is completely isolated in phylogeny, consistent with a range of remarkably distinctive morphological characteristics. Our results clarify the systematics of Didymocarpus and the delimitation between it and related genera with establishment of two new genera.

Key words: Allocheilos, Didymocarpus, Gyrocheilos, Petrocodon, phylogenetic reconstruction, taxonomic treatment.