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The first megafossil record of the genus Neolepisorus Ching from the late Miocene of Yunnan Province, SW China, is reported. Neolepisorus chingii sp. nov. is represented by a simple fertile frond with one line exindusiate, elliptic-fusiform sori along the lower part of the midrib, and a basal contractive sterile frond with a sinuolate margin. The venation is characterized by a strong midrib, prominent zigzagging lateral veins, and reticulate higher order veins with free-ending veinlets (simple or forked once). The combination of these characters confirms the genus Neolepisorus (Polypodiaceae), now distributed in subtropical Southeast Asia, except for one species, which inhabits Madagascar of tropical Africa. It has a distribution center south of the Yangtze River in China. So far, no megafossil assigned to Neolepisorus has been reported, and the occurrence of Neolepisorus chingii in SW China associated with other types of fern occurrence adds increased evidence of fern radiation during the Neogene in Yunnan Province in response to the uplift of the Tibetan Plateau.

Fossil Ginkgophyta are one of the most widely used indicators for estimating the paleoatmospheric CO2 levels from the Triassic to present day. There are quite a few CO2 estimates for the Triassic to Jurassic interval; however, the data from China are still limited. In this study, two fossil Ginkgoites species, Ginkgoites magnifolius Du Toit and Ginkgoites obrutschewii (Seward) Seward, are described based on recent collections from the Upper Triassic and Middle Jurassic in Huating County, Gansu Province, Northwest China. The fossil leaf morphology and epidermal structure were studied and the stomatal parameters were analyzed for the reconstruction of paleoatmospheric CO2 concentrations. The paleoatmospheric CO2 concentration during the Late Triassic of China is estimated for the first time based on fossil material from Gansu. Our fossils yield paleo-CO2 values of 1962 ppmv in the Late Triassic and 1320 ppmv in the Middle Jurassic. Compared with previous estimates of atmospheric CO2 concentration based on stomatal parameter of fossil Ginkgo/Ginkgoites from Northwest China, the change of Jurassic paleo-CO2 levels accord with the trend of CO2 concentration proposed by GEOCARB III and Crustal Production models. The results demonstrate that the paleo-CO2 of the Late Triassic was higher than that of the Early to Middle Jurassic; but an increasing trend of paleo-CO2 could be detected from the Early to the Middle Jurassic. However, the GEOCARBSULF model indicates a decreasing trend during this interval. Therefore, the present data provide an independent check for the paleo-CO2 value estimation based on isotopic analysis.

Macrofossils of Carpinus have been widely reported from the Cenozoic of the Northern Hemisphere. However, the leaf cuticules of the genus have rarely been described. A new species, named Carpinus tengchongensis Dai et B.N. Sun, sp. nov., is identified based on 13 leaf fossils, collected from the late Pliocene Mangbang Formation, Tengchong County of Yunnan Province, China. The important characters of the fossil are its oblong-ovate leaf shape, obliquely cordate base, doubly serrulate margin, straight and moderately thick primary vein, pinnate secondary veins, percurrent tertiary veins, orthogonally reticulate areoles, absence of veinlets, anomocytic stomata with double-layered stomatal rim, well-formed T-pieces and trichome bases, which indicates an affinity within the genus Carpinus section Carpinus subsection Monbeigianae, especially with C. tsaiana. Carpinus fossils were present from the Eocene to Pliocene with disjunctive distribution in the North Temperate Zone, which broadly reflected the present distribution pattern and probably demonstrates the tolerance of Carpinus to environmental change.