Cnesterodon decemmaculatus, which is a freshwater fish abundant in the Pampean region of Argentina, is used as a bioindicator of the status of watercourses throughout its distribution area. This work aimed to (1) evaluate the genetic diversity and population structure of C. decemmaculatus from two river basins in north-eastern Buenos Aires province, Argentina, (2) assess a possible association between genetic structure and the geographical distribution of river basins, including in the analysis data of populations from the south of the province, and (3) validate the use of the species as a bioindicator of the ecological status of watercourses in north-eastern Buenos Aires province. The analysis of a 700-bp fragment of the mitochondrial DNA control region showed moderate to high levels of genetic diversity and lack of genetic structure between the north-eastern basins, validating the use of this species as a bioindicator. Significant differences in genetic structure were found among basins at a regional scale. The lack of genetic structure between the north-eastern basins may result from historical and current events, whereas genetic differences between the north-eastern and southern basins may be explained by the absence of physical connections between them.

中文翻译：

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布宜诺斯艾利斯省不同地理尺度的 Cnesterodon decemmaculatus 种群的系统地理学模式：对其用作生物指示物种的可能影响

Cnesterodon decemmaculatus 是阿根廷潘佩斯地区丰富的淡水鱼，被用作整个分布区域水道状况的生物指标。这项工作旨在 (1) 评估来自阿根廷布宜诺斯艾利斯省东北部两个流域的 C. decemmaculatus 的遗传多样性和种群结构，(2) 评估遗传结构与流域地理分布之间可能的关联，包括在该省南部人口的分析数据中，以及 (3) 验证该物种作为布宜诺斯艾利斯省东北部河道生态状况的生物指标的使用。对线粒体 DNA 控制区的 700 bp 片段的分析表明，东北盆地之间具有中等至高度的遗传多样性和缺乏遗传结构，验证了该物种作为生物指示剂的用途。在区域尺度上，盆地之间的成因结构存在显着差异。东北盆地之间缺乏遗传结构可能是历史和当前事件造成的，而东北盆地和南部盆地之间的遗传差异可能是由于它们之间缺乏物理联系。