PDF(Pubmed)
Abstract：
Most of Switzerland is inhabited by the nominotypical subspecies of the barred grass snake (Natrixhelveticahelvetica), which is characterized by mitochondrial DNA lineage E. Only in the northeast of the country, the common grass snake (N.natrix) occurs and hybridizes with N.h.helvetica in a narrow contact zone. However, we discovered that in southern and western Switzerland barred grass snakes representing another mtDNA lineage (lineage C) are widely distributed. Lineage C is typical for Alpine populations of the southern subspecies N.h.sicula. Our microsatellite analyses of the Swiss samples revealed differences between the two subspecies and also a substructure with two clusters in each subspecies. Furthermore, we discovered a contact and hybrid zone of N.h.helvetica and N.h.sicula along the northern shore of Lake Geneva and also confirm that interbreeding with alien common grass snakes (N.n.moreotica, mtDNA lineage 7) occurs there. This finding is of concern for nature conservation and measures should be taken to prevent further genetic pollution. Using morphometrics, we found no differences between the two subspecies of N.helvetica, while N.natrix was slightly distinct from N.helvetica.
摘要：
瑞士的大部分地区都居住着禁止草蛇（Natrixhelveticaticavetica）的典型亚种，其特征是线粒体DNA谱系E。仅在该国东北部，常见的草蛇(N.natrix）在狭窄的接触区中发生并与N.h.helvetica杂交。然而,我们发现，在瑞士南部和西部，代表另一个mtDNA谱系（谱系C）的禁止草蛇广泛分布。谱系C是南部亚种N.h.sicula的高山种群的典型特征。我们对瑞士样本的微卫星分析揭示了两个亚种之间的差异，以及每个亚种中具有两个簇的子结构。此外，我们在日内瓦湖北岸发现了N.h.helvetica和N.h.sicula的接触和杂交区，并确认了与外来普通草蛇的杂交(N.n.moreotica，mtDNA谱系7）发生在那里。这一发现引起了自然保护的关注，应采取措施防止进一步的遗传污染。使用形态计量学，我们没有发现两个亚种之间的差异，而N.natrix与N.helvetica略有不同。
