Sainouroidea is a molecularly diverse clade of cercozoan flagellates and amoebae in the eukaryotic supergroup Rhizaria. Previous 18S rDNA environmental sequencing of globally collected fecal and soil samples revealed great diversity and high sequence divergence in the Sainouroidea. However, a very limited amount of this diversity has been observed or described. The two described genera of amoebae in this clade are Guttulinopsis, which displays aggregative multicellularity, and Rosculus, which does not. Although the identity of Guttulinopsis is straightforward due to the multicellular fruiting bodies they form, the same is not true for Rosculus, and the actual identity of the original isolate is unclear. Here we isolated amoebae with morphologies like that of Guttulinopsis and Rosculus from many environments and analyzed them using 18S rDNA sequencing, light microscopy, and transmission electron microscopy. We define a molecular species concept for Sainouroidea that resulted in the description of 4 novel genera and 12 novel species of naked amoebae. Aggregative fruiting is restricted to the genus Guttulinopsis, but other than this there is little morphological variation amongst these taxa. Taken together, simple identification of these amoebae is problematic and potentially unresolvable without the 18S rDNA sequence.

ino虫是真核生物超群根瘤菌的鞭毛虫和变形虫的分子多样性进化枝。以前对全球收集的粪便和土壤样品进行的18S rDNA环境测序显示，赛诺伊蚊中具有很大的多样性和高度的序列差异。但是，已经观察到或描述了非常有限的这种多样性。在这个进化枝中，有两个描述的变形虫属是：古特林菌属，表现出聚集性的多细胞性；和玫瑰果属，没有。尽管由于它们形成的多细胞子实体，所以古藤藻的身份很简单，但对于迷迭香却不是这样，而原始隔离株的实际身份尚不清楚。在这里，我们从许多环境中分离出了具有古特氏菌和鞭毛虫形态的变形虫，并使用18S rDNA测序，光学显微镜和透射电子显微镜对它们进行了分析。我们定义了Saurouroidea的分子物种概念，该概念导致描述了4个新属和12个赤裸裸变形虫的新物种。总体结实仅限于古特木霉属，但除此之外，这些类群几乎没有形态变化。综上所述，如果没有18S rDNA序列，对这些变形虫的简单鉴定是有问题的，并且可能无法解决。