Comprehensive multi-locus phylogeny of Old World tree frogs (Anura: Rhacophoridae) reveals taxonomic uncertainties and potential cases of over- and underestimation of species diversity
Comprehensive multi-locus phylogeny of Old World tree frogs (Anura: Rhacophoridae) reveals taxonomic uncertainties and potential cases of over- and underestimation of species diversity
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DOI：
10.1016/j.ympev.2018.07.005
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发表时间：
2018-10-01
影响因子：
4.1
通讯作者：
Brown, Rafe
中科院分区：
文献类型：
--
作者：
Chan, Kin;Grismer, L.;Brown, Rafe
Rhacophoridae是亚洲最多样化的两栖动物家族之一，对其分类学的理解正在迅速扩展，新物种正在稳步描述，并且越来越精细的遗传分辨率。基于距离的方法经常被用来证明或至少支持新物种的识别，特别是在复杂的“神秘”物种，明显的形态分化并不伴随物种形成。然而，没有普遍接受的阈值来区分种内和种间的遗传分化。此外，不加区别地使用分歧阈值来划分物种可能会导致高估或低估物种多样性。为了探索应用分歧尺度的变化范围，并提供一个家庭的评估物种水平的多样性在旧世界树蛙（家庭Rhacophoridae），我们组装了最全面的多位点的进化到目前为止，包括所有18个属和约247个描述的物种（类似于60%的覆盖率）。然后，我们使用的自动条码差距发现（ABGD）的方法，以获得不同的物种划界方案在一系列的事先种内分歧的限制，以评估分歧阈值的一致性，用于划定当前的物种边界。物种丰富的物种起源能够识别出一些分类错误，即不正确的属的位置Chiromantis inexpectatus，我们现在移动到属Feihyla，和来自马来西亚半岛的Rhacophorus bipunctatus的具体身份，我们暂时重新分配到R。红多帕斯。ABGD分析表明，种内和种间分歧的限制之间的重叠：在一些研究中使用的遗传阈值synonymizing类群经常被用于在其他研究中，以证明新物种的识别。该分析还强调了许多可能被拆分或集中的群体，我们将其指定用于未来的检查。我们的大规模和整体的方法，物种水平的系统发生学有助于解决分类的不确定性，揭示可能的新物种，并确定了许多需要严格审查的群体。总体而言，我们表明，旧世界树蛙的分类和进化史是远远没有解决，稳定或充分的特点，在属，种和/或人口的水平。
The family Rhacophoridae is one of the most diverse amphibian families in Asia, for which taxonomic understanding is rapidly-expanding, with new species being described steadily, and at increasingly finer genetic resolution. Distance-based methods frequently have been used to justify or at least to bolster the recognition of new species, particularly in complexes of "cryptic" species where obvious morphological differentiation does not accompany speciation. However, there is no universally-accepted threshold to distinguish intra- from interspecific genetic divergence. Moreover, indiscriminant use of divergence thresholds to delimit species can result in over- or underestimation of species diversity. To explore the range of variation in application of divergence scales, and to provide a family-wide assessment of species-level diversity in Old-World treefrogs (family Rhacophoridae), we assembled the most comprehensive multi-locus phylogeny to date, including all 18 genera and approximately 247 described species (similar to 60% coverage). We then used the Automatic Barcode Gap Discovery (ABGD) method to obtain different species-delimitation schemes over a range of prior intraspecific divergence limits to assess the consistency of divergence thresholds used to demarcate current species boundaries. The species-rich phylogeny was able to identify a number of taxonomic errors, namely the incorrect generic placement of Chiromantis inexpectatus, which we now move to the genus Feihyla, and the specific identity of Rhacophorus bipunctatus from Peninsular Malaysia, which we tentatively reassign to R. rhodopus. The ABGD analysis demonstrated overlap between intra- and interspecific divergence limits: genetic thresholds used in some studies to synonymize taxa have frequently been used in other studies to justify the recognition of new species. This analysis also highlighted numerous groups that could potentially be split or lumped, which we earmark for future examination. Our large-scale and en bloc approach to species-level phylogenetic systematics contributes to the resolution of taxonomic uncertainties, reveals possible new species, and identifies numerous groups that require critical examination. Overall, we demonstrate that the taxonomy and evolutionary history of Old-World tree frogs are far from resolved, stable or adequately characterized at the level of genus, species, and/ or population.