Abstract. Accurate phylogenies are important for understanding the evolutionary histories of organisms, their reproductive traits and ecological habits. The freshwater mussel order Unionida is currently thought to include six families. However, assignment of particular species to these families has been unstable, particularly for species that have been described solely on conchological characters. Unio polystictus Heude, 1877 represents such a species. Based on DNA sequence data from five genes (COI, 16S rRNA, 18S rRNA, 28S rRNA and histone H3) and complete mitochondrial genomes, we investigated the phylogenetic position and generic affinities of U. polystictus using various analytical methods. Both the five-gene and mitogenome datasets strongly supported transferring U. polystictus from Margaritiferidae to Unionidae as Aculamprotula polysticta, comb. res. Our results also supported the following intrageneric relationships: (Aculamprotula tortuosa, ((Aculamprotula polysticta, Aculamprotula scripta), (Aculamprotula fibrosa, Aculamprotula tientsinersis))). In addition, by comparing the morphological features of Aculamprotula (Unionidae, Unioninae), Lamprotula (Unionidae, Gonideinae) and Gibbosula (Margaritiferidae, Gibbosulinae) species, potential issues of relying solely on shell morphology for high-level classification of freshwater mussels are highlighted. Confirmation of classification position and genetic relationship for Aculamprotula polysticta will helpful to understand the ecological characteristics, reproductive strategies and host-fish requirements, which can be inferred from closely related taxa.

中文翻译：

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Aculamprotula polysticta，梳的系统发育位置。资源 （双壳类：Unionidae）从 Unionida 的系统发育关系推断

摘要。准确的系统发育对于了解生物的进化历史、繁殖特征和生态习性非常重要。淡水贻贝目Unionida目前被认为包括六个科。然而，将特定物种分配给这些科一直不稳定，特别是对于仅根据贝壳学特征描述的物种。Unio polystictus Heude, 1877 代表了这样一个物种。基于来自五个基因（COI、16S rRNA、18S rRNA、28S rRNA 和组蛋白 H3）的 DNA 序列数据和完整的线粒体基因组，我们使用各种分析方法研究了 U. polystictus 的系统发育位置和通用亲和力。五基因和有丝分裂基因组数据集都强烈支持将 U. polystictus 从 Margaritiferidae 转移到 Unionidae 作为 Aculamprotula polysticta，梳子。资源 我们的结果还支持以下属内关系：(Aculamprotula tortuosa, ((Aculamprotula polysticta, Aculamprotula scripta), (Aculamprotula fibrosa, Aculamprotula tientsinersis)))。此外，通过比较 Aculamprotula (Unionidae, Unioninae)、Lamprotula (Unionidae, Gonideinae) 和 Gibbosula (Margaritiferidae, Gibbosulinae) 物种的形态特征，突出了仅依靠壳形态对淡水贻贝进行高级分类的潜在问题。确定 Aculamprotula polysticta 的分类位置和亲缘关系将有助于了解生态特征、繁殖策略和寄主对鱼类的需求，这些可以从密切相关的分类群中推断出来。(Aculamprotula tortuosa, ((Aculamprotula polysticta, Aculamprotula scripta), (Aculamprotula fibrosa, Aculamprotula tientsinersis)))。此外，通过比较 Aculamprotula (Unionidae, Unioninae)、Lamprotula (Unionidae, Gonideinae) 和 Gibbosula (Margaritiferidae, Gibbosulinae) 物种的形态特征，突出了仅依靠壳形态对淡水贻贝进行高级分类的潜在问题。确定 Aculamprotula polysticta 的分类位置和亲缘关系将有助于了解生态特征、繁殖策略和寄主对鱼类的需求，这些可以从密切相关的分类群中推断出来。(Aculamprotula tortuosa, ((Aculamprotula polysticta, Aculamprotula scripta), (Aculamprotula fibrosa, Aculamprotula tientsinersis)))。此外，通过比较 Aculamprotula (Unionidae, Unioninae)、Lamprotula (Unionidae, Gonideinae) 和 Gibbosula (Margaritiferidae, Gibbosulinae) 物种的形态特征，突出了仅依靠壳形态对淡水贻贝进行高级分类的潜在问题。确定 Aculamprotula polysticta 的分类位置和亲缘关系将有助于了解生态特征、繁殖策略和寄主对鱼类的需求，这些可以从密切相关的分类群中推断出来。通过比较 Aculamprotula (Unionidae, Unioninae)、Lamprotula (Unionidae, Gonideinae) 和 Gibbosula (Margaritiferidae, Gibbosulinae) 物种的形态特征，突出了仅依靠壳形态对淡水贻贝进行高级分类的潜在问题。确定 Aculamprotula polysticta 的分类位置和亲缘关系将有助于了解生态特征、繁殖策略和寄主对鱼类的需求，这些可以从密切相关的分类群中推断出来。通过比较 Aculamprotula (Unionidae, Unioninae)、Lamprotula (Unionidae, Gonideinae) 和 Gibbosula (Margaritiferidae, Gibbosulinae) 物种的形态特征，突出了仅依靠壳形态对淡水贻贝进行高级分类的潜在问题。确定 Aculamprotula polysticta 的分类位置和亲缘关系将有助于了解生态特征、繁殖策略和寄主对鱼类的需求，这些可以从密切相关的分类群中推断出来。