Gnathorhynchidae is a diverse taxon of predatory eukalyptorhynch flatworms characterized by an armed proboscis. Their present taxonomy is not concordant with what we know of their phylogeny. Further progress in this area is hindered by a lack of information concerning their morphology. As recent studies have shown, a historical reliance on live observations for species descriptions has resulted in a number of errors and omissions. Here, we redescribe the anatomy of the male copulatory organ of Prognathorhynchus busheki using transmission-electron and confocal microscopy, correcting several errors in the original description. Furthermore, we use these results to update our understanding of the anatomy and evolution of male copulatory organs in Gnathorhynchidae and in Platyhelminthes more generally.

中文翻译：

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Prognathorhynchus Busheki（Platyhelminthes，Kalyptorhynchia）雄性交配器的结构

Gnathorhynchidae 是一种多样化的掠食性真桉扁虫类群，其特征是具有武装的长鼻。它们目前的分类与我们对它们的系统发育的了解不一致。由于缺乏有关其形态的信息，该领域的进一步进展受到阻碍。正如最近的研究表明，历史上对物种描述的实时观察的依赖导致了许多错误和遗漏。在这里，我们使用透射电子显微镜和共聚焦显微镜重新描述了 Prognathorhynchus Busheki 雄性交配器官的解剖结构，纠正了原始描述中的几个错误。此外，我们使用这些结果来更新我们对 Gnathorhynchidae 和 Platyhelminthes 中雄性交配器官的解剖结构和进化的理解。