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A new Quercus (Fagaceae) morphospecies is described based on well-preserved fossil leaves. The fossils were collected from Yangyi Formation of the Upper Pliocene at the Yangyi coalmine, Baoshan, western Yunnan, China. Details of the microstructure of mesophyll tissue are preserved because lithification of the fossils was not complete. The fossil laminas possess typical characteristics of Quercus sect Heterobalanus: quite thick and coriaceous cuticle; secondary veins bifurcating near the margin in the middle and top of the leaf; and upper epidermis with adaxial hypodermis. Based on a detailed morphological and anatomical comparison with all living and fossil species of Quercus sect. Heterobalanus, the fossil leaves prove to be different in their sparse and garland-shaped multicellular trichomes on the lower epidermis, and so it is described as a new species Quercus yangyiensis He, Li et Sun sp. nov. The much sparser trichomes of our fossils compare well with those of living Quercus sect. Heterobalanus and indicate a more humid climate during the deposition of the Yangyi Formation in the Late Pliocene. [ABSTRACT FROM AUTHOR]

Abstract: Specimens of Palaeocarya (Juglandaceae) were collected from the upper Pliocene of western Yunnan Province, which is a new geographical and age range record of engelhardioid winged fruits in China. A numerical taxonomic investigation based on 14 morphological characters of fossil and extant specimens of engelhardioid winged fruits in China was conducted using multivariate methods. Phenetic clustering shows that there are four morphotypical groups which we assign to four species. Two groups are assigned to the previously described fossil species, Palaeocarya guangxiensis Li Hao-Min et Chen Yun-Fa, 2003 and Palaeocarya koreanica (Oishi) Manchester, 1987. Two new species are recognized, Palaeocarya yunnanensis and Palaeocarya longialata. These Neogene Engelhardieae fruits provide fossil data for understanding the origin and evolution of the Engelhardia species that now inhabit South China. [Copyright &y& Elsevier]

Abstract: Eight fossil leaves identified as Exbucklandia tengchongensis sp. nov. (Hamamelidaceae) were collected from the Pliocene Mangbang Formation in Tengchong, Yunnan Province, Southwest China. The fossil leaves are characterized by the overall rounded lamina with entire margin, actinodromous venation, and cyclocytic stomata, which suggest the affinity within the genus Exbucklandia, particularly with E. populnea. A survey on the cuticles of the sun and shade leaves of modern E. populnea indicates that the shade leaves generally possess more pronounced undulate anticlinal cell walls and a much lower stomatal density than the sun leaves. Two morphotypes, i.e. sun vs. shade types, of the fossil leaves were therefore recognized. The distribution of the modern Exbucklandia suggests that the genus lives under a warm climate with a mean annual temperature (MAT) from 13 °C to 27 °C and a mean annual precipitation (MAP) from 800 mm to 2500 mm. Hence, E. tengchongensis might also live under a similar climatic condition in the Pliocene. Leaf margin analysis on the Tengchong flora supports this result. The little change of Neogene MAT in Southwest China is therefore supported. [Copyright &y& Elsevier]