Phylogeographic pattern of range expansion provides evidence for cryptic species lineages in Silene nutans in Western Europe

As a result of recent or past evolutionary processes, a single species might consist of distinct Evolutionary Significant Units (ESUs), even corresponding to cryptic species. Determining the underlying mechanisms of range shifts and the processes at work in the build-up of divergent ESUs requires elucidating the factors that contribute to population genetic divergence across a species’ range. We investigated the large-scale patterns of genetic structure in the perennial herbaceous plant species Silene nutans (Caryophyllaceae) in Western Europe. We sampled and genotyped 111 populations using 13 nuclear microsatellite loci and 6 plastid single-nucleotide polymorphisms. Broad-scale spatial population genetic structure was examined using Bayesian clustering, spatial multivariate analyses and measures of hierarchical genetic differentiation. The genotypic structure of S. nutans was typical of a predominantly allogamous mating system. We also identified plastid lineages with no intra-populati...

受近期或过往演化过程影响，单一物种类群可能包含不同的进化显著单元（Evolutionary Significant Units, ESUs），甚至可能对应隐存种。阐明物种类群分布范围变迁的内在机制，以及驱动分化型进化显著单元形成的相关过程，需要明确在物种分布范围内，导致种群遗传分化的各类影响因素。本研究以西欧地区的石竹科（Caryophyllaceae）垂花蝇子草（Silene nutans）这一多年生草本植物为研究对象，探究其遗传结构的大尺度分布模式。我们共采集了111个种群的样本并完成基因分型，所用分子标记包括13个核微卫星位点与6个质体单核苷酸多态性位点。通过贝叶斯聚类、空间多变量分析以及层级遗传分化量度方法，我们对大尺度空间种群遗传结构进行了考察。结果显示，垂花蝇子草的基因型结构符合典型的异交交配系统特征。此外，我们还鉴定出了不存在种群内……的质体谱系