J Syst Evol ›› 2022, Vol. 60 ›› Issue (6): 1440-1452.DOI: 10.1111/jse.12845

• Research Articles • Previous Articles    

Fruits of Firmiana and Craigia (Malvaceae) from the Eocene of the Central Tibetan Plateau with emphasis on biogeographic history

Cédric Del Rio1,2,3*, Teng-Xiang Wang1,4, Shu-Feng Li1,2, Lin-Bo Jia5, Pei-Rong Chen1,4, Robert A. Spicer1,2,6, Fei-Xiang Wu7, Zhe-Kun Zhou1, and Tao Su1,2*   

  1. 1 CAS Key Laboratory of Tropical Forest Ecology, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
    2 Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
    3 Centre de Recherche en Paléontologie–Paris (CR2P), MNHN ‐ Sorbonne Université–CNRS, 43 Rue Buffon, Paris, France
    4 University of Chinese Academy of Sciences, Beijing 100049, China
    5 CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China
    6 School of Environmental, Earth and Ecosystem Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, UK
    7 Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China

    *Authors for correspondence. Cédric Del Rio. E‐mail: cedric.del-rio@mnhn.fr; Tao Su. E‐mail: sutao@xtbg.org.cn
  • Received:2021-12-17 Accepted:2022-02-24 Online:2022-03-16 Published:2022-11-01


The fossil record evidences an old origin and diversification of Malvaceae in the Northern Hemisphere. The central Tibetan Plateau was at a low elevation with a monsoon influence during the Eocene, allowing the development of a subtropical flora containing Malvaceae. The taxonomic study of fossils from the Eocene of what is now the Tibetan Plateau is still ongoing. Malvaceae fossils from the Eocene Jianglang flora, are attributed to sub-families Tilioideae and Sterculioideae, and are compared with modern species. A new specimen of Firmiana is described based on a fruit valve with a pinnate venation, the secondary veins starting at the ventral suture and reaching the midvein, and the seeds attached at the proximal part of the ventral suture. This specimen represents the earliest known occurrence of the genus. A new occurrence of Craigia is also reported based on detached membranous valves of a fruit capsule with a prominent fusiform locular area and radiating venation. Based on the fossil record of Firmiana and its modern distribution, we infer that the genus may have originated in East Asia and subsequently diversified in South China and Southeast Asia. The new occurrence of Craigia indicates that the genus was distributed in humid areas in South, Southwest and North China during the Eocene. Both fossil records evidence the important role that the Tibetan region played in the diversification of plants in East and Southeast Asia.

Key words: biogeography, China, Malvaceae, Paleobotany, Paleogene, plant diversity