Valettietta Lincoln & Thurston, 1983 (Amphipoda: Alicelloidea) is an infrequently sampled genus of scavenging amphipod, with a known bathymetric range from 17–5467 m encompassing a variety of habitats from anchialine caves to abyssal plains. Molecular systematics studies have uncovered cryptic speciation in specimens collected from the abyssal Pacific, highlighting uncertainty in the description of Valettietta anacantha (Birstein & Vinogradov, 1963). Here, we apply an integrative taxonomic approach and describe two new species, Valettietta trottarum sp. nov. and Valettietta synchlys sp. nov., collected at abyssal depths in the Clarion-Clipperton Zone, Pacific Ocean. Both species can be distinguished by characters of the gnathopods, uropod 3, and the inner plate of the maxilliped. Further, molecular phylogenetic analyses of two mitochondrial (16S rDNA and COI) and two nuclear (Histone 3 and 28S rRNA) regions found both new species to form well-supported clades and allowed us to re-identify previously published records based on genetic species delimitation. The biogeography of Valettietta is discussed in light of these re-evaluated records, and a new taxonomic key to the genus is provided. These new taxa highlight the strength of applying an integrated taxonomic approach to uncover biodiversity, which is critical in regions being explored for potential industrial purposes.

中文翻译：

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食腐片足类 Valettietta 属（片足纲：Alicelloidea）的生物地理学和系统发育，以及来自太平洋深海的两个新物种的描述


Valettietta Lincoln & Thurston, 1983（片脚类：Alicelloidea）是一种很少被采样的食腐片脚类属，已知的水深范围为 17-5467 米，涵盖从安奇阿林洞穴到深海平原的各种栖息地。分子系统学研究揭示了从太平洋深海采集的标本中神秘的物种形成，突出了 Valettietta anacantha 描述的不确定性（Birstein & Vinogradov，1963）。在这里，我们应用综合分类方法并描述了两个新物种：Valettietta trottarum sp。十一月和 Valettietta synchlys sp。十一月，在太平洋克拉里昂-克利珀顿区的深海深处收集。这两个物种都可以通过颌足类、尾足类 3 和颌足内板的特征来区分。此外，对两个线粒体（16S rDNA 和 COI）和两个核（组蛋白 3 和 28S rRNA）区域的分子系统发育分析发现，这两个新物种都形成了得到充分支持的进化枝，并使我们能够根据遗传物种界定重新识别先前发表的记录。根据这些重新评估的记录讨论了瓦莱蒂塔的生物地理学，并提供了该属的新分类学索引。这些新的分类群凸显了应用综合分类方法来发现生物多样性的优势，这对于正在探索潜在工业目的的地区至关重要。