J Syst Evol ›› 2019, Vol. 57 ›› Issue (6): 670-677.DOI: 10.1111/jse.12505

• Research Articles • Previous Articles     Next Articles

Extinct genus Lagokarpos reveals a biogeographic connection between Tibet and other regions in the Northern Hemisphere during the Paleogene

He Tang1,2, Jia Liu1, Fei-Xiang Wu3,4, Teresa Spicer5, Robert A. Spicer1,6, Wei-Yu-Dong Deng1,2, Cong-Li Xu1,2, Fan Zhao1,2, Jian Huang1, Shu-Feng Li1, Tao Su1,2*, and Zhe-Kun Zhou1,7*   

  1. 1CAS Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
    2University of Chinese Academy of Sciences, Beijing 100049, China
    3Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China
    4CAS Center for Excellence in Life and Paleoenvironment, Beijing 100044, China
    5State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    6School of Environment, Earth and Ecosystem Sciences, The Open University, Milton Keynes MK76AA, UK
    7Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
  • Received:2019-02-27 Accepted:2019-04-22 Published:2019-11-01

Abstract:

The biodiversity history on the Qinghai–Tibetan Plateau (QTP) has remained unclear for a long time. Recent paleobotanical investigations provide opportunities for revealing the phytogeographic history on the QTP in deep time and for testing phylogeographic hypotheses. Lagokarpos is an extinct genus with unknown modern affinities. It is easily distinguished by its fruits, which have two long wings and an elliptical fruit body. Previously, Lagokarpos fossils have only been found from North America and Germany, ranging from the latest Paleogene to early middle Eocene. Recently, we found fossil fruits of this genus from the Niubao Formation, near Bangoin County in the central QTP. A new species, namely Lagokarpos tibetensis H. Tang, T. Su & Z. K. Zhou sp. nov., is described. This is the first fossil record of the genus in Asia. The occurrence of L. tibetensis indicates a close floristic linkage between the QTP and other floras in the Northern Hemisphere during the Paleogene. According to the floristic assemblages, we suggest the central QTP experienced a tropical or subtropical humid climate during that period.

Key words: biogeography, Lagokarpos, Northern Hemisphere, Paleogene, Qinghai-Tibetan Plateau