We studied phenotypic and genetic differences between individuals of puyen Galaxias maculatus from two sites in the same river basin in Tierra del Fuego National Park, southern South America. Individuals from the two sampling sites presented morphometric and genetic differences. The morphometric differences indicated that individuals from Laguna Negra (LN) were shorter, more robust, and with larger eyes, whereas those from Arroyo Negro (AN) were thinner, elongated, and with smaller eyes. Genetic differences showed that AN individuals had a greater genetic structuration and an older demographic history than LN individuals. From our results, we could affirm that the individuals from the two sampling sites belong to different populations with a high degree of isolation. The demographic history could indicate that the individuals of G. maculatus which migrated to northern areas during the last glaciation settled in the Beagle Channel after its formation. The LN population could have originated after the retreat of the glaciers, migrating from AN. This article is protected by copyright. All rights reserved.

中文翻译：

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双河和内陆的puyen Galaxias maculatus的表型和遗传分化

我们研究了来自南美洲南部火地岛国家公园同一河流流域两个地点的 puyen Galaxias maculatus 个体之间的表型和遗传差异。来自两个采样点的个体呈现出形态测量和遗传差异。形态测量差异表明，内格拉古纳 (LN) 的个体更短、更健壮、眼睛更大，而阿罗约内格罗 (AN) 的个体更瘦、拉长、眼睛更小。遗传差异表明，与 LN 个体相比，AN 个体具有更大的遗传结构和更古老的人口统计学历史。从我们的结果可以肯定，来自两个采样点的个体属于高度隔离的不同种群。人口统计历史可以表明 G. 在末次冰期迁移到北部地区的黄斑鱼在形成后定居在比格尔海峡。LN 种群可能起源于冰川退缩之后，从 AN 迁移。本文受版权保护。版权所有。