REVSYS: Phylogenetic revision of the lichen-forming genus Peltigera (Ascomycota): Disentangling cryptic speciation, phenotypic plasticity, and hybridization

地衣是真菌与绿色藻类和蓝藻中的一种或两种之间非常成功和稳定的互惠关系。尽管Peltigera属是世界性分布的地衣，但由于其丰富的自然资源和突出的形态特征，其形态变异自发现以来一直困扰着分类学家。这一约90个物种的多样性属在生态学上很重要，部分原因是它的蓝藻伴侣固定大气氮。尽管地衣共生的专性，几乎所有的修订研究地衣已限于真菌。在这里，第一次，两个主要的共生伙伴将在遗传上的特点。这将是第一个世界范围内的Peltigera系统发育研究。它将为三个物种复合体的详细分类学修订提供一个框架，这将导致仅在北美就描述了至少10个新物种，并将大大改善现有物种的高度不一致的划界。本研究还将展示蓝藻在塑造真菌进化历史中的作用，反之亦然。除了每年培养一名博士后研究员和一名本科生外，还将引入两名高中生进行共生系统的研究。由此产生的识别Peltigera物种的关键将提高生态学，保护生物学和真菌系统学领域的研究质量。这项修订工作将通过形成一个强大的国际网络，汇集所有致力于Peltigera的领先专家。

Lichens are highly successful and stable mutualistic associations between fungi and either or both green algae and cyanobacteria. Although the cosmopolitan genus Peltigera is one of the earliest described lichens, due to its great abundance in nature and prominent morphological features, its morphological variation has been puzzling taxonomists since its discovery. This diverse genus of approximately 90 species is ecologically important in part because its cyanobacterial partner fixes atmospheric nitrogen. Despite the obligate nature of the lichen symbiosis, nearly all revisionary studies of lichens have been restricted to the fungus. Here, for the first time, the two main symbiotic partners will be characterized genetically. This will be the first worldwide phylogenetic study of Peltigera. It will provide a framework for detailed taxonomic revisions of three species complexes, which will lead to the description of at least ten new species in North America alone, and will drastically improve the highly inconsistent delimitation of existing species. This study will also demonstrate the role cyanobacteria can play in shaping evolutionary histories of fungi and vice versa.In addition to the training of one postdoctoral researcher and one undergraduate student each year, two high school students will be introduced to conducting research on symbiotic systems. The resulting keys for the identification of Peltigera species will improve the quality of research in the fields of ecology, conservation biology and fungal systematics. This revisionary work will bring together all leading experts working on Peltigera by forming a strong international network.