Abstract：
A new speciesStenamoeba aeronautan. sp.was isolated from a culture of large thecamoebids during laboratory studies. Our study of this species showed almost complete morphological identity with the well-known speciesStenamoeba stenopodia. Despite the morphological similarity and proximity in the phylogenetic tree, significant differences in the sequence of the 18S rRNA gene forced us to recognize it as a new species. Known species ofStenamoebahave noticeable morphological differences, but the discovery of the new speciesshows that cryptic speciation appears in this amoeba genus as well as in many others, likeThecamoebaorVannella. In contrast with many other amoebae genera, the number of available 18S rRNA gene sequences exceeds that of morphologically described isolates. So, it is not yet possible to suggest the application of the names of monophyletic species groups, as it was recently proposed forThecamoebaspecies, since every clade ofStenamoebacontains both sequences of species with known morphology and with unknown ones.Overall, the present study further confirms that probably almost all \"classical\" morphospecies of amoebae may represent a cluster of a sibling species, showing remarkable differences at the molecular level.
摘要：
一种新种阿米巴aeronautan。sp.在实验室研究期间从大型哺乳动物培养物中分离出来。我们对该物种的研究表明，与众所周知的物种Stenamoeba几乎具有完整的形态同一性。尽管系统发育树的形态相似性和接近性，18SrRNA基因序列的显着差异迫使我们将其识别为新物种。已知的Stenamoeba物种具有明显的形态差异，但是新物种的发现表明，在这个变形虫属以及许多其他物种中都出现了神秘的物种形成，像ThecamoebaorVannella.与许多其他变形虫属相反，可用的18SrRNA基因序列的数量超过了形态学描述的分离株。所以,尚不可能建议应用单系物种组的名称，正如最近提出的，因为Stenamoebacon的每个进化枝都包含具有已知形态和未知形态的物种序列。总的来说,本研究进一步证实，变形虫的几乎所有“经典”形态物种都可能代表同胞物种的集群，在分子水平上表现出显著的差异。
