Range-limited endemic taxa are threatened by loss of genomic diversity, which can lead to extirpation and extinction. The imperiled and narrowly distributed edaphic endemic Carex scirpoidea subsp. convoluta (Cyperaceae), which is primarily limited to alvar soils on the northern shores of Lake Huron in North America, exhibits such risk. In contrast, the conspecific C. scirpoidea subsp. scirpoidea is widely distributed across a vast geographical range and occupies various arctic and alpine habitat types. Using ddRADseq, population genomic analyses of 11 North American populations of C. scirpoidea including five subsp. convoluta populations revealed similar-to-higher levels of genomic diversity in the latter compared to its more widely distributed conspecific subsp. scirpoidea. Dioecy and a nearly obligate outcrossing mode of reproduction have likely contributed to the maintenance of genomic diversity in subsp. convoluta, preventing inbreeding depression, and contributing to the evolutionary potential of populations of this taxon. Phylogenomic and Bayesian analyses of ddRADseq data revealed that subsp. convoluta is paraphyletic with Eastern North American subsp. scirpoidea populations, suggesting that it best be considered a locally adapted ecotype. Furthermore, Eastern North America populations of both taxa arose from populations that likely occupied periglacial refugia south of the Laurentide Ice Sheet, where they no longer occur. Herein, we identify conservation units among the sampled Eastern North American C. scirpoidea populations to aid management efforts, which we suggest should include habitat protection and replanting for habitat restoration purposes.

范围有限的地方性分类单元受到基因组多样性丧失的威胁，这可能导致灭绝和灭绝。受损和分布狭窄的地方性地方性Carex scirpoidea亚种。卷地（莎草科），它主要限于休伦湖在北美洲的北岸阿尔瓦土壤，表现出这样的风险。相反，同种的C. scirpoidea亚种。鞘翅目广泛分布在广阔的地理范围内，并具有各种北极和高山生境类型。使用ddRADseq，11组的北美人群的人口基因组分析C. scirpoidea包括五个亚种。卷积与后者分布更广泛的同种亚种相比，后者的种群显示出相似至更高水平的基因组多样性。鞘翅目。雌雄同体和几乎专横的异型繁殖可能有助于维持亚种中的基因组多样性。卷积，防止近亲衰退，并有助于该分类群的进化潜力。ddRADseq数据的系统学和贝叶斯分析表明该亚种。convoluta与北美洲东部亚种有共生关系。小号cirpoidea人口，这建议最好将其视为本地适应的生态型。此外，北美东部的两个类群的种群起源于可能在Laurentide冰盖以南的沿冰期避难所居住的种群，在那里不再发生。在此，我们在采样的北美东部弯孢子种群中确定了保护单位，以协助管理工作，我们建议应包括栖息地保护和为恢复栖息地而进行重新种植。