Phylogenomic analyses of brachyuran crabs support early divergence of primary freshwater crabs
Phylogenomic analyses of brachyuran crabs support early divergence of primary freshwater crabs
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短蟹的系统发育分析支持初级淡水蟹的早期分化
DOI：
10.1016/j.ympev.2019.02.001
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发表时间：
2019-06-01
影响因子：
4.1
通讯作者：
Tsang, Ling Ming
中科院分区：
文献类型：
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作者：
Ma, Ka Yan;Qin, Jing;Tsang, Ling Ming
最近的化石校准的分子系统学研究表明，短体动物在白垩纪和早第三纪经历了快速辐射，导致许多早期的分叉谱系被较短的节间隔开，仍然难以分辨。在这里，我们首次利用22科30种短肢动物的转录组数据进行了短肢动物的系统发育分析。对包含372个假定的同源基因座(246,590个碱基)的数据集进行了分析，并包括来自21个新生成的转录本的数据。除了少数例外，所有的系统发育分析都恢复了一致的、高度分辨的和得到很好支持的短毛类动物的系统发育。与前人的工作一致，这一系统发育表明，初级淡水蟹在短臂类进化的早期分化，成为胸吸虫的姊妹门，从而支持最近关于建立初级淡水蟹亚纲的建议。在我们的分析中，异孔动物之间的家族间关系得到了很好的解决，但胸孔动物内部的关系仍然存在问题。系统发育学分析显然为解决短毛类动物的关系提供了强有力的手段，但未来的研究将极大地受益于增加转录组数据的分类单元采样。
Recent fossil calibrated molecular phylogenies have revealed that the Brachyura underwent rapid radiation during the Cretaceous and Early Tertiary, resulting in many early diverging lineages separated by short inter-nodes that remain difficult to resolve. Here we present the first phylogenomic analyses of Brachyura using transcriptome data from 30 brachyuran species and 22 families. Analyses were carried out on a dataset containing 372 putative homologous loci (246,590 bps) and included data from 21 newly generated transcriptomes. With minor exceptions, all phylogenetic analyses recovered a congruent, highly resolved and well supported brachyuran phylogeny. Consistent with previous work, this phylogeny suggests that primary freshwater crabs diverged early in brachyuran evolution, falling sister to Thoracotremata, thus supporting recent proposal for establishment of subsection Potamoida for primary freshwater crabs. The interfamilial relationships among heterotremes were well resolved in our analyses but those within Thoracotremata remained problematic. Phylogenomic analyses clearly provide a powerful means for resolving brachyuran relationships, but future studies would benefit greatly from increased taxon sampling of transcriptome data.