Abstract The genus Willisornis is endemic to the Amazon Basin, inhabiting upland terra firme forest, with two species and seven subspecies currently recognized. Despite numerous systematic studies, a taxonomically-dense sampled phylogeny for Willisornis is still lacking, which, combined with evidence of paraphyly and gene flow between its recognized species, underscores the uncertainty concerning species limits and evolutionary history of the genus. Here we present phylogenies and population genetic analyses, including all currently recognized Willisornis taxa, relating them to patterns of plumage variation, and reconstructing the spatiotemporal context of diversification in the genus. Our analyses have uncovered 13 independent genetic lineages in the genus, and the monophyly of all currently named taxa, which also showed robust plumage diagnoses. However, deeply coalesced genetic lineages were also found within most Willisornis taxa, for which no consistent variation in plumage was found. The diversification of the genus Willisornis is related to hydrographic and climate change cycles across Amazonia since the Plio-Pleistocene, with most genetic lineages originating in the past one million years. Based on our findings, we recommend the recognition of a total of six species in Willisornis (one of which polytypic) based on the congruency between deeply coalesced lineages and consistent plumage diagnoses.

中文翻译：

---

亚马逊特有谱系的鳞背蚁鸟（Willisornis：Thmnophilidae）的多样化和物种限制

摘要 Willisornis 属是亚马逊盆地的特有种，栖息在高地的陆地森林中，目前已确认有两个种和七个亚种。尽管进行了大量系统研究，但仍然缺乏对 Willisornis 的分类学密集的系统发育样本，结合其公认物种之间的并系和基因流动的证据，强调了有关物种限制和该属进化历史的不确定性。在这里，我们介绍了系统发育和种群遗传分析，包括所有目前公认的 Willisornis 分类群，将它们与羽毛变异模式联系起来，并重建该属多样化的时空背景。我们的分析揭示了该属中 13 个独立的遗传谱系，以及所有目前命名的分类群的单一性，这也显示出强大的羽毛诊断。然而，在大多数 Willisornis 分类群中也发现了深度合并的遗传谱系，但没有发现羽毛的一致变化。Willisornis 属的多样化与自 Plio-Pleistocene 以来亚马逊河流域的水文和气候变化周期有关，大多数遗传谱系起源于过去一百万年。根据我们的研究结果，我们建议根据深度融合的血统和一致的羽毛诊断之间的一致性，在威利鸟中识别总共六个物种（其中一个是多型的）。Willisornis 属的多样化与自 Plio-Pleistocene 以来亚马逊流域的水文和气候变化周期有关，大多数遗传谱系起源于过去一百万年。根据我们的研究结果，我们建议根据深度合并的血统和一致的羽毛诊断之间的一致性，在威利鸟中识别总共六个物种（其中一个是多型的）。Willisornis 属的多样化与自 Plio-Pleistocene 以来亚马逊流域的水文和气候变化周期有关，大多数遗传谱系起源于过去一百万年。根据我们的研究结果，我们建议根据深度合并的血统和一致的羽毛诊断之间的一致性，在威利鸟中识别总共六个物种（其中一个是多型的）。