Eukaryotrophic protists are ecologically significant and possess characteristics key to understanding the evolution of eukaryotes; however, they remain poorly studied, due partly to the complexities of maintaining predator–prey cultures. Kaonashia insperata, gen. nov., et sp. nov., is a free-swimming biflagellated eukaryotroph with a conspicuous ventral groove, a trait observed in distantly related lineages across eukaryote diversity. Di-eukaryotic (predator–prey) cultures of K. insperata with three marine algae (Isochrysis galbana, Guillardia theta, and Phaeodactylum tricornutum) were established by single-cell isolation. Growth trials showed that the studied K. insperata clone grew particularly well on G. theta, reaching a peak abundance of 1.0 × 10⁵ ± 4.0 × 10⁴ cells ml⁻¹. Small-subunit ribosomal DNA phylogenies infer that K. insperata is a stramenopile with moderate support; however, it does not fall within any well-defined phylogenetic group, including environmental sequence clades (e.g. MASTs), and its specific placement remains unresolved. Electron microscopy shows traits consistent with stramenopile affinity, including mastigonemes on the anterior flagellum and tubular mitochondrial cristae. Kaonashia insperata may represent a novel major lineage within stramenopiles, and be important for understanding the evolutionary history of the group. While heterotrophic stramenopile flagellates are considered to be predominantly bacterivorous, eukaryotrophy may be relatively widespread amongst this assemblage.

中文翻译：

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Kaonashia insperata gen. 等 nov.，一种真核鞭毛虫，代表异养原生藻菌的一个新的主要谱系

真核营养原生生物具有重要的生态意义，并具有了解真核生物进化的关键特征；然而，由于维持捕食者-被捕食者文化的复杂性，对它们的研究仍然很少。Kaonashia insperata , gen. 十一月，等。nov.，是一种自由游动的双鞭毛真核生物，具有明显的腹侧沟，这是在真核生物多样性的远亲谱系中观察到的特征。K的双真核（捕食者-被捕食者）培养物。 通过单细胞分离建立了具有三种海洋藻类（Isochrysis galbana、Guillardia theta和Phaeodactylum tricornutum ）的insperata 。生长试验表明，所研究的K . insperata克隆在G上生长得特别好。 theta，达到峰值丰度 1.0 × 10 ⁵  ± 4.0 × 10 ⁴ cells ml ^-1。小亚基核糖体 DNA 系统发育推断K . insperata是具有中等支撑力的原生藻菌；然而，它不属于任何明确定义的系统发育群，包括环境序列进化枝（例如MAST），并且其具体位置仍未解决。电子显微镜显示与原生藻菌亲和力一致的特征，包括前鞭毛和管状线粒体嵴上的鞭丝。Kaonashia insperata可能代表了原生藻菌中一个新的主要谱系，对于理解该群体的进化历史非常重要。虽然异养原生藻菌鞭毛虫被认为主要是食细菌的，但真核营养可能在该组合中相对普遍。