Data from: Genomic data reveal ancient microendemism in forest scorpions across the California Floristic Province

The California Floristic Province (CFP) in western North America is a globally significant biodiversity hotspot. Elucidating patterns of endemism and the historical drivers of this diversity has been an important challenge of comparative phylogeography for over two decades. We generated phylogenomic data using ddRADseq to examine genetic structure in Uroctonus forest scorpions, an ecologically restricted and dispersal-limited organism widely distributed across the CFP north to the Columbia River. We coupled our genetic data with species distribution models (SDMs) to determine climatically suitable areas for Uroctonus both now and during the Last Glacial Maximum (LGM). Based on our analyses, Uroctonus is composed of two major genetic groups that likely diverged over two million years ago. Each of these groups itself contains numerous genetic groups that reveal a pattern of vicariance and microendemism across the CFP. Migration rates among these populations are low. SDMs suggest forest scorpion habitat has remained relatively stable over the last 21,000 years, consistent with the genetic data. Our results suggest tectonic plate rafting, mountain uplift, river drainage formation, and climate-induced habitat fragmentation have all likely played a role in the diversification of Uroctonus. The intricate pattern of genetic fragmentation revealed across a temporal continuum highlights the potential of low-dispersing species to shed light on small-scale patterns of biodiversity and the underlying processes that have generated this diversity in biodiversity hotspots.北美西部的加利福尼亚植物区（California Floristic Province, CFP）是全球重要的生物多样性热点区域。二十余年来，阐明该区域的特有性分布模式与生物多样性的历史驱动因子，一直是比较系统地理学领域的核心研究难题。本研究采用ddRADseq技术构建系统基因组数据，以探究林蝎属（Uroctonus）森林蝎的遗传结构——该类群生态位受限且扩散能力有限，广泛分布于北至哥伦比亚河的加利福尼亚植物区范围内。我们将遗传数据与物种分布模型（species distribution models, SDMs）相结合，分别预测了当前与末次盛冰期（Last Glacial Maximum, LGM）时期林蝎属的气候适宜分布区。分析结果显示，林蝎属包含两个主要的遗传支系，二者的分化时间可能距今已超200万年；每个主支系内部又包含多个次级遗传支系，展现出加利福尼亚植物区内的异域分化与微特有性分布格局。这些种群间的基因流水平极低。物种分布模型结果表明，过去21000年间林蝎的栖息环境相对稳定，这与遗传数据的分析结果一致。本研究结果证实，板块漂流、山脉隆升、河流水系形成以及气候驱动的生境破碎化，均对林蝎属的物种分化起到了关键推动作用。本研究通过时间梯度揭示出复杂的遗传碎片化模式，凸显了扩散能力有限的物种可为解析生物多样性热点区域内的局域生物多样性格局及其形成的底层过程提供重要研究视角。