Universidad Nacional Autónoma de México, Instituto de Biología, Laboratorio de Helmintología, México D. F. México.
PLoS One. 2013 Sep 27;8(9):e74419. doi: 10.1371/journal.pone.0074419. eCollection 2013.
In this paper, we analyse the distributional patterns of adult helminth parasites of freshwater fishes with respect to the main hydrological basins of Mexico. We use the taxonomic distinctness and the variation in taxonomic distinctness to explore patterns of parasite diversity and how these patterns change between zoogeographical regions. We address questions about the factors that determine the variation of observed diversity of helminths between basins. We also investigate patterns of richness, taxonomic distinctness and distance decay of similarity amongst basins. Our analyses suggest that the evolution of the fauna of helminth parasites in Mexico is mostly dominated by independent host colonization events and that intra--host speciation could be a minor factor explaining the origin of this diversity. This paper points out a clear separation between the helminth faunas of northern--nearctic and southern--neotropical components in Mexican continental waters, suggesting the availability of two distinct taxonomic pools of parasites in Mexican drainage basins. Data identifies Mexican drainage basins as unities inhabited by freshwater fishes, hosting a mixture of neotropical and nearctic species, in addition, data confirms neotropical and neartic basins/helminth faunas. The neotropical basins of Mexico are host to a richest and more diversified helminth fauna, including more families, genera and species, compared to the less rich and less diverse helminth fauna in the nearctic basins. The present analysis confirms distance--decay as one of the important factors contributing to the patterns of diversity observed. The hypothesis that helminth diversity could be explained by the ichthyological diversity of the basin received no support from present analysis.
本文分析了墨西哥主要水系淡水鱼类的成年寄生虫的分布模式。我们使用分类学差异和分类学差异的变化来探索寄生虫多样性的模式，以及这些模式如何在动物地理区域之间变化。我们探讨了决定寄生虫多样性在流域之间变化的因素。我们还研究了流域之间丰富度、分类学差异和相似性距离衰减的模式。我们的分析表明，墨西哥寄生虫区系的进化主要受独立宿主定殖事件的支配，而种内进化可能是解释这种多样性起源的一个次要因素。本文指出了墨西哥大陆水域中北近北极和南新热带成分的寄生虫区系之间的明显分离，这表明墨西哥流域中存在两个不同的寄生虫分类群。数据表明，墨西哥流域是由淡水鱼类栖息的统一体，除了新热带和近北极物种的混合外，还确认了新热带和近北极流域/寄生虫区系。与近北极流域中较不丰富和多样化的寄生虫区系相比，墨西哥的新热带流域拥有更丰富和多样化的寄生虫区系，包括更多的科、属和种。本分析证实了距离衰减是导致观察到的多样性模式的重要因素之一。寄生虫多样性可以用流域的鱼类多样性来解释的假设没有得到本分析的支持。
