The seahorse Hippocampus guttulatus reaches its highest abundance in confined environments, where it has unique biological and ecological traits that suggest significant genetic differentiation among populations. In the present study, we aimed to reveal the genetic structure of this species by analysing eight microsatellite loci and a mitochondrial DNA region (cytochrome b) of eight populations from the Central–Western Mediterranean Sea, including lagoon sites. Levels of genetic diversity, as measured by the total number of alleles, number of private alleles, allelic richness and heterozygosity, ranged from low to moderate. The overall value of inbreeding was high, indicating a deficiency in heterozygotes. The haplotype network had a star-like construction, with the most common haplotype present in all populations. Data from the two molecular markers congruently displayed a similar pattern and revealed low genetic differentiation, notwithstanding predictions based on species traits. The observed genetic structure is probably the result of both historical population demographic events and current gene flow. The investigated lagoons, however, revealed a unique genetic profile, which is especially highlighted by the Taranto population. At this site, the results also showed altered values of observed/expected heterozygosity and allelic richness, a characteristic of marginal populations. Our study suggests that lagoon populations should be managed as distinct genetic units.

中文翻译：

---

地中海中西部长鼻海马海马guttulatus的遗传结构

海马海马guttulatus在有限的环境中达到最高的丰度，在这里它具有独特的生物学和生态特征，表明种群之间存在显着的遗传分化。在本研究中，我们旨在通过分析来自中西部地中海（包括泻湖场）的八个种群的八个微卫星基因座和线粒体DNA区域（细胞色素b）来揭示该物种的遗传结构。通过等位基因总数，私人等位基因数目，等位基因丰富性和杂合性来衡量，遗传多样性的水平范围从低到中等。近交的总价值很高，表明杂合子不足。单倍型网络具有星形结构，在所有人群中都存在最常见的单倍型。尽管基于物种特征的预测，来自两个分子标记的数据一致显示出相似的模式并显示出较低的遗传分化。观察到的遗传结构可能是历史人口统计事件和当前基因流动的结果。然而，经过调查的泻湖显示出独特的遗传特征，塔兰托种群尤其突出。在该站点，结果还显示观察到/预期的杂合性和等位基因丰富度（边缘人群的特征）的值发生了变化。我们的研究表明，泻湖种群应作为不同的遗传单位进行管理。观察到的遗传结构可能是历史人口统计事件和当前基因流动的结果。然而，经过调查的泻湖显示出独特的遗传特征，塔兰托种群尤其突出。在该站点，结果还显示观察到/预期的杂合性和等位基因丰富度（边缘人群的特征）的值发生了变化。我们的研究表明，泻湖种群应作为不同的遗传单位进行管理。观察到的遗传结构可能是历史人口统计事件和当前基因流动的结果。然而，经过调查的泻湖显示出独特的遗传特征，塔兰托种群尤其突出。在该站点，结果还显示观察到/预期的杂合性和等位基因丰富度（边缘人群的特征）的值发生了变化。我们的研究表明，泻湖种群应作为不同的遗传单位进行管理。