Arrigoni Roberto, Berumen Michael L, Stolarski Jaroslaw, Terraneo Tullia I, Benzoni Francesca
Red Sea Research Center, Division of Biological and Environmental Science and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia.
Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, Warsaw, PL-00-818, Poland.
Cladistics. 2019 Jun;35(3):301-328. doi: 10.1111/cla.12346. Epub 2018 Jun 21.
Extant biodiversity can easily be underestimated owing to the presence of cryptic taxa, even among commonly observed species. Scleractinian corals are challenging to identify because of their ecophenotypic variation and morphological plasticity. In addition, molecular analyses have revealed the occurrence of cryptic speciation. Here, we describe a new cryptic lobophylliid genus and species Paraechinophyllia variabilis gen. nov., sp. nov., which is morphologically similar to Echinophyllia aspera and E. orpheensis. The new taxon occurs in Mayotte Island, Madagascar, the Gulf of Aden and the Red Sea. Six molecular markers (COI, 12S, ATP6-NAD4, NAD3-NAD5, histone H3 and ITS) and 46 morphological characters at three different levels (macromorphology, micromorphology and microstructure) were examined. The resulting molecular phylogenetic reconstruction showed that Paraechinophyllia gen. nov. represents a distinct group within the Lobophylliidae that diverged from the lineage leading to Echinophyllia and Oxypora in the Early Miocene, approximately 21.5 Ma. The morphological phylogenetic reconstruction clustered Paraechinophyllia gen. nov., Echinophyllia and Oxypora together in a single clade. A sole morphological character, calice relief, discriminated Paraechinophyllia gen. nov. from the latter two genera, suggesting that limited morphological variation has occurred over a long period. These results highlight the importance of cryptic taxa in reef corals, with implications for population genetics, ecological studies and conservation.
由于存在隐存分类单元，即使在常见物种中，现存生物多样性也很容易被低估。石珊瑚由于其生态表型变异和形态可塑性，很难进行识别。此外，分子分析揭示了隐存物种形成的存在。在此，我们描述了一个新的隐存叶状珊瑚属和物种——可变拟刺叶珊瑚（Paraechinophyllia variabilis），新属新种，其形态与粗糙刺叶珊瑚（Echinophyllia aspera）和奥氏刺叶珊瑚（E. orpheensis）相似。这个新分类单元分布于马约特岛、马达加斯加、亚丁湾和红海。我们检测了六个分子标记（COI、12S、ATP6-NAD4、NAD3-NAD5、组蛋白H3和ITS）以及三个不同水平（宏观形态、微观形态和微结构）的46个形态特征。由此得到的分子系统发育重建结果表明，拟刺叶珊瑚属代表叶状珊瑚科内一个独特的类群，在中新世早期（约2150万年前）从导致刺叶珊瑚属和尖杯珊瑚属的谱系中分化出来。形态系统发育重建将拟刺叶珊瑚属、刺叶珊瑚属和尖杯珊瑚属聚在一个单一的分支中。一个唯一的形态特征——萼部起伏，将拟刺叶珊瑚属与后两个属区分开来，这表明在很长一段时间内形态变异有限。这些结果突出了隐存分类单元在珊瑚礁珊瑚中的重要性，对种群遗传学、生态学研究和保护具有启示意义。
