Precambrian fossils of fungi are sparse, and the knowledge of their early evolution and the role they played in the colonization of land surface are limited. Here, we report the discovery of fungi fossils in a 810 to 715 million year old dolomitic shale from the Mbuji-Mayi Supergroup, Democratic Republic of Congo. Syngenetically preserved in a transitional, subaerially exposed paleoenvironment, these carbonaceous filaments of ~5 μm in width exhibit low-frequency septation (pseudosepta) and high-angle branching that can form dense interconnected mycelium-like structures. Using an array of microscopic (SEM, TEM, and confocal laser scanning fluorescence microscopy) and spectroscopic techniques (Raman, FTIR, and XANES), we demonstrated the presence of vestigial chitin in these fossil filaments and document the eukaryotic nature of their precursor. Based on those combined evidences, these fossil filaments and mycelium-like structures are identified as remnants of fungal networks and represent the oldest, molecularly identified remains of Fungi.

中文翻译：

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新元古代页岩中真菌微化石的分子鉴定。

前寒武纪真菌化石稀疏，对其早期进化的了解以及它们在土地表面定植中的作用是有限的。在这里，我们报告了在刚果民主共和国姆布吉-玛伊超级集团的810至7.15亿年历史的白云质页岩中发现真菌化石的情况。这些在宽度上约5μm的碳质细丝同系保存在过渡的，暴露于地下的古环境中，表现出低频分隔（伪分隔）和高角度分支，可以形成密集的相互连接的菌丝状结构。使用一系列显微镜（SEM，TEM和共聚焦激光扫描荧光显微镜）和光谱技术（拉曼，FTIR和XANES），我们证明了这些化石丝中残留壳多糖的存在，并证明了其前体的真核性质。