The Late Triassic Marattiaceae And Dipteridaceae And Their Palaeoecology In Yipinglang, Yunnan

The Mesozoic fossils of Yunnan Province are very famous world widely; especially the iconic Early-Middle Jurassic dinosaurs and the Late Triassic plants. The non-marine Upper Triassic coal-bearing beds yield abundant exceptionally well preserved fossil plants, which provide a unique window into the early evolutionary history of vegetation in South China. However, previous studies mainly focused on the gross morphological description of fossil plants, so the true biological features and the palaeoecology of the plants remains poorly understood. We systematically studied the families Marattiaceae and Dipteridaceae, including Marattiopsis (7 specimens), Thaumtopteris (23 specimens), Dictyophyllum (172 specimens) and Clathropteris (62 specimens) from three fossil localities of Yipinglang Coal Field, i.e. Xinwujing, Xingxiaojing and Yangqiaoqing coal mines.Based on detailed examinations of the sterile and fertile organs, two species of Marattiopsis, five species of Thaumatopteris, six species of Dictyophyllum, five species of Clathropteris were recognised in the flora. The author comparatively studied nine species of Marattiopsis, eleven species of Thaumatopteris, ten species of Dictyophyllum, nine species of Clathropteris occurred in the Mesozoic of China, and discussed the relationship between their diversity and tempo-spatial distribution and the palaeoclimatic and palaeogeographic changes.Four feeding damage types, i.e. marginal feeding, hole feeding, skeletonization, surface feeding were recognised in Dipteridaceae (257 specimens) in the Yipinglang Coal Field. Based on statistically analysis of the occurrence frequency of each damage types in individual species, a thorough land palaeoecology (especially the plant-insect interactions) was reconstructed for the first time during the Late Triassic in South China.