A new phylogeographic perspective on a classical refugial area - colonization patterns and geneflow of spectacled salamanders (genus Salamandrina) in Italy

意大利半岛被认为是欧洲冰河时代的主要避难所之一。对意大利不同分类群的系统地理研究发现，与北部地区相比，最南端(卡拉布里亚)拥有更强的分化谱系。我们计划阐明意大利特有的两个不同物种的进化史，这两个物种分别是尖吻鳗(Salamandrina Perspicillata)和大火蜥蜴(S.terdigitata)。这些谱系在几百万年前分裂开来，虽然只在北部发现了透气螺旋藻，但毛端螺旋藻仅限于南部。人们预计南部物种的遗传多样性要高得多，但这些物种的系统地理初步数据表明，遗传多样性的模式与同源两栖动物物种的遗传多样性模式完全不一致。在这两个物种中，遗传分化似乎非常低。因此，尽管它们独立的进化历史，但相似或可能相同的机制肯定独立地塑造了这两个物种区域内的种群结构。此外，我们还将分析勒皮尼山脉细毛虫种群的遗传结构，以帮助了解种群内的遗传多样性水平和(亚)种群间扩散的空间尺度上的基因流动，这些种群的生态和生活史参数是众所周知的。这项研究在样本大小和分析的标记数量方面将是史无前例的，我们希望在不同的地理尺度上找到真实人口历史的良好近似值。

Peninsular Italy is considered one of the main ice-age refugia of Europe. Phylogeographic studies of various Italian taxa have found that the southernmost part (Calabria) harbors more strongly differentiated lineages compared to northern regions. We plan to elucidate the evolutionary history of the two distinct species of spectacled salamanders, Salamandrina perspicillata and S. terdigitata, which are endemic to Italy. These lineages split several million years ago and while S. perspicillata is only found in north, S. terdigitata is restricted to the south. One would expect much higher genetic diversity in the southern species, but preliminary data on the phylogeography of these species indicate a pattern of genetic diversity that is in complete discordance with those found in syntopic amphibian species. Genetic differentiation seems remarkably low in both species. Thus, despite their independent evolutionary history, similar or maybe the same mechanisms must have shaped the population structure within the area of both species independently. Additionally, we will analyze the finescale population genetic structure of S. perspicillata in the Lepini Mountains to help understand the level genetic diversity within and gene flow on the spatial scale of dispersal among (sub)populations, for which ecological and life-history parameter are well known. This study will be unprecedented in regard to sample size and numbers of markers analyzed, and we expect to find a good approximation of the true demographic histories on different geographic scales.