Hypotrichia are a group with the most complex morphology and morphogenesis within the ciliated protists. The classification of Gastrostyla-like species, a taxonomically difficult group of hypotrichs with a common ventral cirral pattern but various dorsal and ontogenetic patterns, is poorly understood. Hence, systematic relationships within this group and with other taxa in the subclass Hypotrichia remain unresolved. 18S rRNA gene sequence of a new Gastrostyla-like taxon was obtained. Phylogenetic analyses based on the 18S rRNA gene sequences indicate that this ciliate represents a new genus that is closely related to Heterourosomoida and Kleinstyla within the oxytrichid clade of the Hypotrichia. However, the position of this cluster remains unresolved. All three genera deviate from the typical oxytrichids by their incomplete (or lack of) dorsal kinety fragmentation during morphogenesis. Morphology and morphogenesis of this newly discovered form, Heterogastrostyla salina nov. gen., nov. spec., are described. Heterogastrostyla nov. gen., is characterised as follows: more than 18 fronto-ventral-transverse cirri, cirral anlagen V and VI develop pretransverse cirri, and dorsal ciliature in Urosomoida-like pattern. Similar to the CEUU-hypothesis about convergent evolution of urostylids and uroleptids, we speculate that the shared ventral cirral patterns of Gastrostyla-like taxa might have resulted from convergent evolution.

中文翻译：

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Gastrostyla亲和属的系统关系的见解，以及关于盐碱土纤毛虫新属和新物种（原生动物，纤毛虫）的报道。

壶毛虫是纤毛原生生物中形态和形态发生最复杂的群体。对Gastrostyla样物种的分类了解甚少，Gastrostyla样物种是分类学上较困难的一组下鞭毛，具有常见的腹侧环状模式，但背背和个体发育模式多种。因此，该组内以及与亚纲Hypotrichia中其他类群的系统关系仍未解决。获得了一种新的类似Gastrostyla的分类单元的18S rRNA基因序列。基于18S rRNA基因序列的系统发育分析表明，该纤毛虫代表了一个新属，该属与Hypotrichia的氧化三体进化枝中的Heterourosomoida和Kleinstyla密切相关。但是，此群集的位置仍未解决。这三个属由于其在形态发生过程中不完整（或缺乏）的背侧运动学碎裂而与典型的三旋毛虫不同。这种新发现的形式，Hterogastrostyla salina nov的形态和形态发生。gen。，nov。规格。Heterogastrostyla nov。的特征如下：超过18个额腹-腹侧横卷，腹侧anlagen V和VI发展为横横前卷，背睫毛呈Urosomoida样模式。类似于CEUU假说，尿嘧啶和尿肽类趋同进化的假说，我们推测，胃类Gastrostyla类群的共同腹侧c回模式可能是趋同进化引起的。Heterogastrostyla nov。的特征如下：超过18个额腹-腹侧横卷，腹侧anlagen V和VI发展为横横前卷，背睫毛呈Urosomoida样模式。类似于CEUU假说，尿嘧啶和尿肽类趋同进化的假说，我们推测，胃类Gastrostyla类群的共同腹侧c回模式可能是趋同进化引起的。Heterogastrostyla nov。的特征如下：超过18个额腹-腹侧横卷，腹侧anlagen V和VI发展为横横前卷，背睫毛呈Urosomoida样模式。类似于CEUU假说，尿嘧啶和尿肽类趋同进化的假说，我们推测，胃类Gastrostyla类群的共同腹侧c回模式可能是趋同进化引起的。