Cryptic species are black boxes of taxonomy and need to be addressed with an integrative taxonomic approach. Simulium (Diptera: Simuliidae) may contain a substantial amount of cryptic species diversity due to its large cross-continental distribution and habitat-based canalization in taxonomic characters. Except for Simulium sergenti, the following six species Simulium equinum, Simulium paraequinum, Simulium pseudequinum, Simulium turgaicum, Simulium balcanicum, and Simulium lineatum are the most widely distributed species of the subgenus Wilhelmia in the Palearctic region. However, the conspecific diversity and evolutionary history of these species are not yet well understood. In this study, therefore, we used mitochondrial COI and nuclear ITS1-2 sequences to perform species delimitation tests, and demographic and phylogeographic analyses to understand candidate species and evolutionary history of the seven species. While our results did not support the species status of S. balcanicum, S. turgaicum, and S. lineatum, it did suggest several candidate species within S. equinum and S. pseudequinum. Molecular clock analysis revealed that significant branching events occurred in the Pliocene, and demographic fluctuations in the populations occurred intensely during the Pleistocene. Overall, the results indicated that Anatolia has served as a significant refugium for ancestral haplotypes, and it is an important dispersal corridor between the eastern and western Palearctic for Wilhelmia species.

中文翻译：

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形态物种中的物种水平隐藏多样性：基于安纳托利亚的进化和 Simulium （Wilhelmia） 马种群（双翅目：Simuliidae）中的隐蔽物种多样性


隐晦物种是分类学的黑匣子，需要通过综合分类学方法来解决。Simulium （Diptera： Simuliidae） 可能包含大量神秘的物种多样性，因为它的跨大陆分布很大，并且分类特征中基于栖息地的运河化。除 Simulium sergenti 外，以下六个物种 Simulium equinum、Simulium paraequinum、Simulium pseudequinum、Simulium turgaicum、Simulium balcanicum 和 Simulium lineatum 是古北界地区分布最广泛的威廉亚属物种。然而，这些物种的种群多样性和进化历史尚不清楚。因此，在本研究中，我们使用线粒体 COI 和核 ITS1-2 序列进行物种划定测试，以及人口学和系统地理学分析，以了解候选物种和七个物种的进化历史。虽然我们的结果不支持 S. balcanicum、S. turgaicum 和 S. lineatum 的物种地位，但它确实表明了马链球菌和假马链球菌中的几个候选物种。分子钟分析显示，上新世发生了显著的分支事件，而种群的人口波动在更新世期间发生得很剧烈。总体而言，结果表明，安纳托利亚已成为祖先单倍型的重要避难所，是威廉木属物种在东西古北界之间的重要传播走廊。