This study represents the first phylogenetic reconstruction of Synchaetidae (Rotifera, Monogononta) and combines one morphological and two molecular data sets to derive the most comprehensive database for this taxon to date. Overall, 19 species were examined both morphologically (light‐ and scanning electron microscopy of habitus and trophi) and genetically (COI and 18S rRNA genes), thereby delivering new morphological information as well as the first molecular data for several species. Our results strongly support the monophyly of each of the three genera within Synchaetidae, with Synchaeta being the sister taxon of Polyarthra and Ploesoma. Resolution within each genus, however, was more poorly supported, possibly because of high levels of missing data for the more poorly known species that were also not re‐discovered and revised in the present study. Nevertheless, an evolutionary reconstruction based on the total evidence topology indicates that the common ancestor of Synchaetidae was a rotatorivorous and pelagic freshwater rotifer exhibiting slightly enlarged lamellar trophi that were adapted to an enhanced pumping function. These features together with several, additional key character transformations (e.g., hatching independently from benthic or periphytic habitats) probably account for the success of Synchaetidae in pelagic environments and their being one of the most widely distributed and abundant rotifer taxa.

中文翻译：

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重点放在Synchaeta上的Synchaetidae（Rotifera：Monogononta）的进化：结合分子和形态学数据的综合方法

这项研究代表了Synchaetidae（Rotifera，Monogononta）的第一个系统发育重建，并结合了一个形态学数据和两个分子数据集，以得出迄今为止该分类单元最全面的数据库。总体上，对19个物种进行了形态学（光和扫描电子显微镜观察到的习性和营养杯）和遗传学（COI和18S rRNA基因），从而提供了新的形态学信息以及一些物种的第一批分子数据。我们的研究结果有力地支持每一个内Synchaetidae三个属的单系，与Synchaeta是的妹妹类群多肢和Ploesoma。但是，每个属中的解析得到的支持较差，这可能是由于缺少更多鲜为人知的物种的数据而导致的，这些数据在本研究中也没有重新发现和修订。然而，基于总证据拓扑结构的进化重建表明，突触科的共同祖先是轮虫和浮游的淡水轮虫，其片状营养体稍大，适应了增强的抽水功能。这些特征以及一些其他关键特征的转变（例如，独立于底栖或边缘生境的孵化）可能解释了Synchaetidae在远洋环境中的成功，并且它们是分布最广，数量最多的轮虫类之一。