Occurrence of Christella (Thelypteridaceae) in Southwest China and its indications of the paleoenvironment of the Qinghai–Tibetan Plateau and adjacent areas  

作　　者：Cong-Li Xu Tao Su Jian Huang Yong-Jiang Huang Shu-Feng Li Yi-Shan Zhao Zhe-Kun Zhou 

机构地区：[1]Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Menglun, Mengla 666303, Yunnan, China [2]Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China [3]University of the Chinese Academy of Sciences, Beijing 100049, China [4]Faculty of Electronic and Mechanical Engineering, Hunan University of Science and Technology, Xiangtan 411201, Hunan, China

出　　处：《Journal of Systematics and Evolution》2019年第2期169-179,共11页植物分类学报（英文版）

基　　金：National Natural Science Foundation of China (41661134049, U1502231, 31470325);the Strategic Priority Research Program of CAS (XDA20070301);Key Research Program of Frontier Sciences, CAS (QYZDB-SSWSMC016), a grant from the Natural Environment Research Council (NE/P013805/1);and the Youth Innovation Promotion Association, CAS (2017439).

摘　　要：The uplift of the Qinghai–Tibetan Plateau dramatically changed the regional topography and climate, profoundly impacting the distribution of many plant lineages. Plant responses to environmental changes are particularly prominent in lineages that require ecological factors differentiated from those present before the uplift of the QTP. Two fossil occurrences of Christella H. Lév., Fl. Kouy–Tchéou (Thelypteridaceae), a fern genus now distributed mainly at low elevations of the pantropics with warm and moist habitats, are described based on fossilized Cenozoic leaf fronds recovered from SW China: late Paleocene Christella nervosa (J. R. Tao) C. L. Xu, T. Su & Z. K. Zhou comb. nov. found in Liuqu, southern Tibet and middle Miocene Christella sp. recovered from the Jinggu Basin in western Yunnan. The frond fossils from both sites share key morphological characteristics that diagnose these fossils as Christella. After detailed comparisons, we further clarified Christella papilio (C. Hope) Holttum, a species distributed in warm, humid habitats at altitudes no more than 1300?m, as the nearest living relative of C. nervosa. This finding suggested that southern Tibet had not reached its present elevation during the late Paleocene (ca. 56 Ma). We propose that the uplift, accompanied by severe cooling and aridification after the late Paleocene, caused the disappearance of Christella in southern Tibet, whereas paleoenvironmental conditions enabled the genus to survive in Yunnan. Our study provides the first example of distributional constraints of ferns in SW China in response to paleoenvironmental changes in the Qinghai–Tibetan Plateau and nearby areas.

关 键 词：biodiversity CENOZOIC Christella FERN fossil the Qinghai–Tibetan Plateau 

分 类 号：TP317[自动化与计算机技术—计算机软件与理论]