Abstract Evolutionary processes related to climatic changes and ecological factors, such as microhabitat affinities and food specialization, can be important contributors to phylogeographic discordance between codistributed and related species. Here, we evaluate the evolutionary histories of two cactophilic and codistributed Drosophila species (Diptera: Drosophilidae) from South America, Drosophila antonietae and Drosophila meridionalis, where they use mainly Cereus hildmaniannus (Cactoideae: Cereeae) as host, using mitochondrial DNA sequences and species distribution modeling. The diversification of both species was estimated during the Pleistocene. For both species, the distribution of suitable areas through the Last Glacial period to the present showed a similar dynamic from Andes Valley through east and through the Paraná-Paraguay river basin to the Atlantic coastline. The current distribution of D. antonietae was influenced by demographic expansion and putative migration route from northwest to south and then to coast, with two genetic incipient groups with bidirectional genetic flow between them. For D. meridionalis, we suggested a migration route from south to north as well as to coast, with three genetic groups deeply structured with no evidence of demographic expansion. Our comparative results showed that the Quaternary paleoclimatic dynamic has had a similar role in both species (displacement of the high suitability areas) with similar routes but in different directions. Additionally, the Araucaria forest represents a putative biogeographic barrier for Drosophila species and also for host C. hildmaniannus. The phylogeographical differences between these species related to geographical distribution, genetic structure, and demographic history could be explained for differences to adaptation and plasticity to explore a new host.

中文翻译：

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南美洲开放地区两种共分布嗜嗜果蝇物种（Drosophila repleta group）对第四纪景观和气候变化的独立进化响应

摘要 与气候变化和生态因素相关的进化过程，如微生境亲和力和食物专业化，可能是共同分布和相关物种之间系统地理学不一致的重要原因。在这里，我们评估了来自南美洲的两种嗜食性和共同分布的果蝇物种（双翅目：Drosophilidae）的进化历史，Drosophila antonietae 和 Drosophila meridionalis，它们主要使用 Cereus hildmaniannus（Cactoideae：Cereeae）作为宿主，使用线粒体物种分布 DNA 序列造型。在更新世期间估计了这两个物种的多样化。对于这两个物种，从末次冰期到现在，适宜地区的分布显示出从安第斯山谷到东部和巴拉那-巴拉圭河流域到大西洋海岸线的类似动态。D. antonietae 目前的分布受人口扩张和推测的从西北向南再向海岸的迁移路线的影响，两个遗传初期群体之间存在双向遗传流动。对于 D. meridionalis，我们提出了一条从南到北以及到海岸的迁徙路线，三个基因组结构很深，没有人口扩张的证据。我们的比较结果表明，第四纪古气候动态在两个物种（高适宜区的位移）中具有相似的作用，路线相似，但方向不同。此外，南洋杉森林代表了果蝇物种和寄主 C. hildmaniannus 的假定生物地理屏​​障。这些物种之间与地理分布、遗传结构和人口历史有关的系统地理学差异可以解释为适应和可塑性的差异以探索新宿主。