van Riemsdijk Isolde, Arntzen Jan W, Bogaerts Sergé, Franzen Michael, Litvinchuk Spartak N, Olgun Kurtuluş, Wielstra Ben
Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, The Netherlands.
Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, The Netherlands.
Mol Phylogenet Evol. 2017 Sep;114:73-81. doi: 10.1016/j.ympev.2017.05.028. Epub 2017 Jun 13.
The banded newt (genus Ommatotriton) is widely distributed in the Near East (Anatolia, Caucasus and the Levant) - an understudied region from the perspective of phylogeography. The genus is polytypic, but the number of species included and the phylogenetic relationships between them are not settled. We sequenced two mitochondrial and two nuclear DNA markers throughout the range of Ommatotriton. For mtDNA we constructed phylogenetic trees, estimated divergence times using fossil calibration, and investigated changes in effective population size with Bayesian skyline plots and mismatch analyses. For nuDNA we constructed phylogenetic trees and haplotype networks. Species trees were constructed for all markers and nuDNA only. Species distribution models were projected on current and Last Glacial Maximum climate layers. We confirm the presence of three Ommatotriton species: O. nesterovi, O. ophryticus and O. vittatus. These species are genetically distinct and their most recent common ancestor was dated at ∼25Ma (Oligocene). No evidence of recent gene flow between species was found. The species show deep intraspecific genetic divergence, represented by geographically structured clades, with crown nodes of species dated ∼8-13Ma (Miocene to Early Quaternary); evidence of long-term in situ evolution and survival in multiple glacial refugia. While a species tree based on nuDNA suggested a sister species relationship between O. vittatus and O. ophryticus, when mtDNA was included, phylogenetic relationships were unresolved, and we refrain from accepting a particular phylogenetic hypothesis at this stage. While species distribution models suggest reduced and fragmented ranges during the Last Glacial Maximum, we found no evidence for strong population bottlenecks. We discuss our results in the light of other phylogeographic studies from the Near East. Our study underlines the important role of the Near East in generating and sustaining biodiversity.
带状蝾螈（Ommatotriton属）广泛分布于近东地区（安纳托利亚、高加索和黎凡特）——从系统地理学角度来看，这是一个研究较少的地区。该属是多型的，但所包含的物种数量及其之间的系统发育关系尚未确定。我们在Ommatotriton的整个分布范围内对两个线粒体和两个核DNA标记进行了测序。对于线粒体DNA，我们构建了系统发育树，使用化石校准估计分歧时间，并通过贝叶斯天际线图和错配分析研究有效种群大小的变化。对于核DNA，我们构建了系统发育树和单倍型网络。为所有标记和仅核DNA构建了物种树。物种分布模型被投影到当前和末次盛冰期的气候层上。我们确认了三种Ommatotriton物种的存在：内氏蝾螈（O. nesterovi）、眉纹蝾螈（O. ophryticus）和带纹蝾螈（O. vittatus）。这些物种在基因上是不同的，它们最近的共同祖先可追溯到约2500万年前（渐新世）。未发现物种之间近期基因流动的证据。这些物种显示出深度的种内遗传分歧，以地理结构的分支为代表，物种的冠节点可追溯到约800 - 1300万年前（中新世至早更新世）；这证明了长期原地进化以及在多个冰川避难所中的生存。虽然基于核DNA的物种树表明带纹蝾螈和眉纹蝾螈之间存在姐妹物种关系，但当纳入线粒体DNA时，系统发育关系无法解析，因此我们在此阶段暂不接受特定的系统发育假说。虽然物种分布模型表明在末次盛冰期期间分布范围缩小且碎片化，但我们未发现强烈种群瓶颈的证据。我们根据近东地区的其他系统地理学研究讨论了我们的结果。我们的研究强调了近东地区在生物多样性产生和维持中的重要作用。
