Dosidicus gigas is an economically important species distributed in the Eastern Pacific Ocean. Unraveling the genetic population structure of this species is crucial to ensure its fishery sustainability and management. Mitochondrial DNA sequences and nuclear neutral loci are useful to understand how historical and contemporary factors drive the genetic population structure of species. However, most studies investigating genetic structuring of D. gigas from its northern and southern populations rely on patterns identified using mitochondrial genes. The use of both types of DNA markers is especially relevant for marine species with high dispersal capabilities such as D. gigas. Here, we describe the genetic structure of D. gigas using partial sequences of the mitochondrial gene NADH dehydrogenase subunit 2 and nuclear microsatellite loci in populations of the northern hemisphere from the Costa Rica Thermal Dome and off Ecuador; and, of the southern hemisphere from the South Equatorial Current and off Peru. Statistical parsimony network and Bayesian analyses from mitochondrial sequences revealed three historical maternal lineages in both hemispheres, with high levels of genetic differentiation and signatures of population expansion during the late Pleistocene. Use of Discriminant Analysis of Principal Component (DAPC) with microsatellite loci of mature and immature individuals showed the presence of at least two contemporary genetic stocks homogeneously co-distributed in both northern and southern hemispheres, which can be explained by the biological characteristics of D. gigas and the variable oceanographic conditions of the Eastern Pacific Ocean. Overall, our findings indicate that cooperation between countries with intensive fishing will benefit the sustainability of D. gigas.

中文翻译：

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线粒体和微卫星 DNA 标记的模式描述了东太平洋洪堡鱿鱼 Dosidicus gigas 的历史和当代动态

Dosidicus gigas 是分布于东太平洋的重要经济物种。解开该物种的遗传种群结构对于确保其渔业可持续性和管理至关重要。线粒体 DNA 序列和核中性位点有助于了解历史和当代因素如何驱动物种的遗传种群结构。然而，大多数调查来自北部和南部种群的 D. gigas 的遗传结构的研究依赖于使用线粒体基因识别的模式。两种类型的 DNA 标记的使用对于具有高扩散能力的海洋物种尤其相关，例如 D. gigas。在这里，我们描述了 D 的遗传结构。gigas 使用线粒体基因 NADH 脱氢酶亚基 2 的部分序列和来自哥斯达黎加热穹顶和厄瓜多尔附近的北半球种群中的核微卫星位点；和，来自南赤道流和秘鲁附近的南半球。统计简约网络和来自线粒体序列的贝叶斯分析揭示了两个半球的三个历史母系谱系，在更新世晚期具有高水平的遗传分化和种群扩张特征。对成熟和未成熟个体的微卫星位点使用主成分判别分析 (DAPC) 表明至少存在两个同时均匀分布在北半球和南半球的当代遗传种群，这可以通过 D. gigas 的生物学特征和东太平洋多变的海洋条件来解释。总的来说，我们的研究结果表明，密集捕捞国家之间的合作将有利于 D. gigas 的可持续性。