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Fossil epifoliar fungi are valuable indicators of paleoenvironment and paleoecology. The Meliolaceae, members of which typically inhabit the surface of living plants as biotrophs or pathogens, is one of the largest groups of epifoliar fungi. In this study, we report a novel fossil species of Meliolinites Selkirk (fossil Meliolaceae), Meliolinites tengchongensis, on the lower epidermis of compressed fossil Rhodoleia (Hamamelidaceae) leaves from the Upper Pliocene Mangbang Formation of Tengchong, Yunnan, southwestern China. Meliolinites tengchongensis is characterized by web-like, superficial, brown to dark brown, septate, and branching mycelia bearing 2-celled appressoria and unicellular phialides. The fungal colonies also include ellipsoidal, 5-celled, 4-septate ascospores and dark brown perithecia with suborbicular outline and verrucose surface. The well-preserved vegetative and reproductive organs help us to explore the potential disease process of the new fossil species. Besides, the presence of fungal remains indicates that the fungal taxon might have maintained its host preference since at least the Late Pliocene. Furthermore, the occurrence of both fossil fungi and their host plants in Tengchong indicate a subtropical–tropical, warm, and humid climate during the Late Pliocene, whereas the distribution pattern of the fungi on the host leaves suggests that Rhodoleia may have been a part of the middle–upper canopies in the Tengchong Late Pliocene multilayered forest. [ABSTRACT FROM AUTHOR]

Bauhinia s.l. widely distributed across tropical and subtropical regions and has a complex taxonomic history and divided into two main clades: the Bauhinia clade and the Phanera clade. The fossil records of Bauhinia s.l. are predominantly found in Asia, but they were reported worldwide. In this study, we describe two leaf fossil taxa of Bauhinia s.l. and one legume fossil taxon from western Yunnan, China. The results of the morphological and phylogenetic analysis indicate that the newly identified species Bauhinia tengchongensis sp. nov. is a part of the Phanera clade. The phylogenetic analysis suggests that the divergence between the two clades likely occurred before the late Oligocene. The fossil distribution and phylogenetic data suggest that South China may have been an early diversity centers for Bauhinia s.l. Given the distribution of extant Bauhinia s.l. members and the warmer climate during the Late Pliocene in Tengchong, we propose that the cooling period following the Pliocene in western Yunnan may have driven the migration of some thermophilic Bauhinia s.l. species towards Eastern and Southern China. • Two new leaf fossils respectively belong to the Bauhinia clade and the Phanera clade. • Phylogeny indicates the classification of fossils and evolution of Bauhinia s.l. • The distribution of Bauhinia s.l. affected by rapid uplift of the Hengduan Mountains and global climate cooling. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate genomic variations of two Chinese Yersinia pestis isolates that were isolated from different plague foci obtained from vaccine strain EV76 from the Yunnan province of China. Methods: A microarray containing 12 000 probes covering the entire genome of seven Yersinia pestis and two Yersinia pseudotuberculosis strains, was used. PCR assays were performed to confirm microarray results. Results: The gene variations detected included the absence of five genes related to the synthesis of betaine in both EV76 and another sequenced attenuated strain, KIM D27. Several genes related to phage-related membrane proteins were found to be absent in the Antiqua biovar Yunnan strain, 485, which was isolated from a rodent plague foci. Conclusion: These findings provide initial insight into the distinct strains isolated from natural foci, within their genomic context, including Yunnan Y. pestis strains. This information will be used therefore to establish subsequent comparisons of these sequences with published complete genomes of other strains. [Copyright &y& Elsevier]