Land use changes are threatening the maintenance of biodiversity. Genetic diversity is one of the main indicators of biological diversity and is highly important as it shapes the capability of populations to respond to environmental changes. We studied eleven populations of Pseudoeurycea robertsi, a micro-endemic and critically endangered species from the Nevado de Toluca Volcano, a mountain that is part of the Trans-Mexican Volcanic Belt, Mexico. We sequenced the mitochondrial cytochrome b gene from 71 individuals and genotyped 9 microsatellites from 150 individuals. Our results based on the cytochrome b showed two divergent lineages, with moderate levels of genetic diversity and a recently historical demographic expansion. Microsatellite-based results indicated low levels of heterozygosity for all populations and few alleles per locus, as compared with other mole salamander species. We identified two genetically differentiated subpopulations with a significant level of genetic structure. These results provide fundamental data for the development of management plans and conservation efforts for this critically endangered species.

中文翻译：

---

墨西哥中部极度濒危的罗伯茨假溪蝾螈（Pseudoeurycea robertsi）的遗传多样性和人口统计学

土地利用的变化正在威胁生物多样性的维护。遗传多样性是生物多样性的主要指标之一，非常重要，因为它塑造了人口应对环境变化的能力。我们研究了 11 个 Pseudoeurycea robertsi 种群，这是一种来自内华达托卢卡火山的微型地方性和极度濒危物种，托卢卡火山是墨西哥跨墨西哥火山带的一部分。我们对 71 个人的线粒体细胞色素 b 基因进行了测序，并对 150 个人的 9 颗微卫星进行了基因分型。我们基于细胞色素 b 的结果显示了两个不同的谱系，具有中等水平的遗传多样性和最近的历史人口扩张。基于微卫星的结果表明所有群体的杂合性水平低，每个基因座的等位基因很少，与其他鼢蝾物种相比。我们确定了两个具有显着遗传结构水平的遗传分化亚群。这些结果为制定该极度濒危物种的管理计划和保护工作提供了基本数据。