McLean Bryan S, Rickart Eric A, Cook Joseph A, Guralnick Robert P, Burgin Connor J, Lohr Kristin
Department of Biology, University of North Carolina at Greensboro, 321 McIver Street, Greensboro, NC 27402, United States.
Natural History Museum of Utah, University of Utah, 301 Wakara Way, Salt Lake City, UT 84108, United States.
J Mammal. 2024 Dec 12;106(2):406-430. doi: 10.1093/jmammal/gyae135. eCollection 2025 Apr.
The "small-eared" species group of ground squirrels (Sciuridae: Xerinae: Marmotini) is endemic to the Great Basin, United States, and surrounding cold desert ecosystems. Most specific and subspecific lineages in this group occupy narrow geographic ranges, and some are of significant conservation concern; despite this, current taxonomy remains largely based on karyotypic or subtle pelage and morphological characteristics. Here, we leverage 2 multilocus DNA sequence data sets and apply formal species delimitation tests alongside morphometric comparisons to demonstrate that the most widespread small-eared species ( Kennicott, 1863 sensu lato; Piute Ground Squirrel) is comprised of 2 nonsister and deeply divergent lineages. The 2 lineages are geographically separated by the east-west flowing Snake River in southern Idaho, with no sites of sympatry currently known. Based on robust support across the nuclear genome, we elevate populations previously attributed to from north of the Snake River to species status under the name (Merriam 1913) and propose the common name "Snake River Plains Ground Squirrel" for this taxon. We delimit 2 subspecies within ; (Merriam 1913) in western Idaho and (Merriam 1913) in eastern Idaho. is endemic to Idaho and has a maximal range area of roughly 29,700 km spanning 22 counties but occurs discontinuously across this area. Our work substantially expands knowledge of ground squirrel diversity in the northern Great Basin and Columbia Plateau and highlights the difficulty in delimiting aridland mammals whose morphological attributes are highly conserved.
地松鼠（松鼠科：旱獭亚科：旱獭族）的“小耳”物种群是美国大盆地及周边寒冷沙漠生态系统特有的。该群体中的大多数物种和亚种谱系占据狭窄的地理范围，其中一些受到了重大的保护关注；尽管如此，目前的分类学仍主要基于核型或细微的皮毛和形态特征。在这里，我们利用两个多基因座DNA序列数据集，并应用正式的物种界定测试以及形态测量比较，以证明分布最广的小耳物种（肯尼科特，1863年广义；派尤特地松鼠）由两个非姐妹且分化程度很深的谱系组成。这两个谱系在地理上被爱达荷州南部自东向西流淌的蛇河隔开，目前尚无已知的同域分布地点。基于整个核基因组的有力支持，我们将先前归属于蛇河北部的种群提升为独立物种，命名为（梅里亚姆，1913年），并为该分类单元提出通用名称“蛇河平原地松鼠”。我们在该物种内界定了两个亚种；爱达荷州西部的（梅里亚姆，1913年）和爱达荷州东部的（梅里亚姆，1913年）。该物种是爱达荷州特有的，最大分布范围约为29,700平方公里，跨越22个县，但在该区域内分布不连续。我们的工作极大地扩展了对大盆地北部和哥伦比亚高原地松鼠多样性的认识，并凸显了界定形态特征高度保守的干旱地区哺乳动物的困难。
