Neomphaloidean gastropods are endemic to chemosynthesis-based ecosystems ranging from hot vents to organic falls, and their diversity and evolutionary history remain poorly understood. In the southwestern Pacific, deep-sea hydrothermal vents on back-arc basins and volcanic arcs are found in three geographically secluded regions: a western region around Manus Basin, an eastern region around North Fiji and Lau Basins, and the intermediate Woodlark Basin where active venting was confirmed only recently, on the 2019 R/V L’Atalante CHUBACARC expedition. Although various lineages of neomphaloidean snails have been detected, typically restricted to one of the three regions, some of these have remained without names. Here, we use integrative taxonomy to describe three of these species: the neomphalid Symmetromphalus mithril sp. nov. from Woodlark Basin and the peltospirids Symmetriapelta becki sp. nov. from the eastern region and Symmetriapelta radiata sp. nov. from Woodlark Basin. A combination of shell sculpture and radular characters allow the morphological separation of these new species from their described congeners. A molecular phylogeny reconstructed from 570 bp of the mitochondrial cytochrome c oxidase subunit I gene confirmed the placement of the three new species in their respective genera and the superfamily Neomphaloidea. The finding of these new gastropods, particularly the ones from the Woodlark Basin, provides insights and implications on the historical role of Woodlark as a dispersing centre, in addition to highlighting the uniqueness of the Woodlark faunal community.

中文翻译：

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西南太平洋深海热喷口新腹足动物的综合分类


新蟾蜍腹足动物是从热喷口到有机瀑布等以化学合成为基础的生态系统中特有的物种，但它们的多样性和进化历史仍然知之甚少。在西南太平洋，弧后盆地和火山弧上的深海热液喷口存在于三个地理上僻静的区域：马努斯盆地周围的西部地区、北斐济和劳盆地周围的东部地区以及活跃的中间伍德拉克盆地。最近，在 2019 年 R/V L'Atalante CHUBACARC 探险中，通风问题才得到证实。尽管已经发现了各种新螺类蜗牛谱系，通常仅限于这三个地区之一，但其中一些仍然没有名字。在这里，我们使用综合分类法来描述其中的三个物种：新鼠科 Symmetromphalus mithril sp。十一月来自 Woodlark 盆地和 peltospirids Symmetriape​​lta becki sp。十一月来自东部地区和 Symmetriape​​lta radiata sp。十一月来自伍德拉克盆地。贝壳雕塑和齿状特征的结合使这些新物种与所描述的同类物种在形态上得以区分。从线粒体细胞色素 c 氧化酶亚基 I 基因的 570 bp 重建的分子系统发育证实了这三个新物种在各自属和新脐总科中的位置。这些新腹足动物，特别是来自伍德拉克盆地的腹足动物的发现，除了强调伍德拉克动物群落的独特性之外，还为伍德拉克作为分散中心的历史作用提供了见解和启示。