| Abstract Detail
Paleobotany Li, Xiangchuan [1], Xiao, Liang [2], Hui, Zhengchuang [3], Yao, Yunzhi [4], Ren, Dong [4], He , Wenlong [5], Yang, Qiang [6]. Diverse fossils from the Miocene of Zeku in the northeastern Tibetan Plateau indicate high historical biodiversity and favorable paleoenvironment. Today, the northern Tibetan Plateau (TP) is a high and remote part in Central Asia far away from oceans, and is renowned for its vast Gobi deserts and huge treeless and grassy steppes with a harsh climate featuring aridity or semiaridity and severe winter cold. Compared with equivalent latitude lowlands in eastern China, this large area has more limited terrestrial biodiversity, especially in arborescent plants. Recently, a wide array of fossils has been reported from the Miocene lagerstätte indicate high biodiversity and favorable paleoenvironment. Firstly, as to plant macrofossils, a fruit species Koelreuteria quasipaniculata of Sapindaceae is established based on several exquisitely preserved fossil membranous capsules. This is a characteristic anemochorous tree. Two fossil fruit species of Fabaceae are recognized as Podocarpium podocarpum and Cercis zekuensis. Furthermore, most co-occurring plant fossils are numerous winged fruits or seeds which belong to Acer, Ulmus, Fraxinus and Pinaceae etc. They are also typical of wind dispersal and predominately show temperate affinities. The palynological assemblage includes Picea (ca. 52%), Pinus (ca. 8%), Abies (ca. 7%), Tsuga (ca. 5%), Ulmus (ca. 24%), Betula (ca. 3%) and Acer (ca. 1%) and reflects a deciduous broad-leaved and coniferous forest, probably indicative of a vertical distribution during the Miocene. Secondly, concerning fossil insects, a cicada species Cixius discretus was described here. This is the first record of Cixiidae from the Miocene of the Tibetan Plateau. The diet of extant Cixius adults consist entirely of various shrubs and trees, which demonstrates the above mentioned view that a temperate forest occurred here in the past. According to the preliminary identification results, other fossil insect taxa, e.g. Wesmaelius, Mycetophila, Corixidae and Odonata, support the view that the fossil biota was buried not in the central area of a large lake but in a swamp. Besides, a lot of bird feathers are also discovered along with fossil insects and plants, and some can be assignable to Passer montanus saturatus stejneger, which prefers tree holes for nesting. Overally, high biodiversity in the northeastern TP during the Miocene corroborated by the Zeku biota, indicates that past terrestrial animals and plants in this region sensitively respond to a more favorable habitat caused by the Oligo-Miocene climate change and the intensified East Asian summer monsoon.
1 - University Of Florida, Florida Museum Of Natural History, 1659 Museum Rd., Gainesville, FL, 32611, United States
2 - Chang'an University, School of Earth Sciences and Resources, 126 Yanta Road, Xi'an, 710054, CN
3 - Henan University, College of Environment and Planning, National Demonstration Center for Environmental and Planning, Kaifeng, 475004, CN
4 - Capital Normal University, College of Life Sciences, Beijing, 100048, CN
5 - Xian University of Science and Technology, College of Geology and Environment, Xi'an, 710054, CN
6 - Guangzhou University, School of Life Sciences, Guangzhou, 510006, CN
Keywords:
Fossils
Miocene
northeastern Tibetan Plateau
historical biodiversity
paleoenviroment.
Presentation Type: Poster
Session: P, Paleobotany Posters
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 5:00 PM Time and date to be determined
Number: PPB008
Abstract ID:859
Candidate for Awards:None |
