Paragymnodinium verecundum Yokouchi & Horiguchi sp. nov. was isolated from sand samples collected at Kitsunezaki, Miyagi Prefecture, Japan, and described based on observations using light and scanning and transmission electron microscopy, together with molecular analysis. The cells were 9.4–17.1 μm long and 5.7–13.6 μm wide and showed a benthic lifestyle. They possessed a sulcal extension‐like furrow on the episome, an eyespot, nematocysts and multiple chloroplasts with separated thylakoids. They ingested prey cells by engulfment, indicating a mixotrophic nutrition. These characters are shared with a known species of the genus Paragymnodinium, P. stigmaticum. However, unlike P. stigmaticum, P. verecundum showed negative phototaxis and possessed a pusule. Additional differences in the ultrastructure of the nematocysts and the flagellar apparatus indicated that these two dinoflagellates are different species. A phylogenetic analysis based on concatenated 18S and 28S ribosomal DNA sequences recovered P. verecundum in a robust clade of species of Paragymnodinium within the clade Gymnodinium sensu stricto. The sister to P. verecundum was P. stigmaticum, but they were clearly separated. Therefore, this dinoflagellate was concluded to be a new species in the genus Paragymnodinium.

中文翻译：

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副伞菌verecundum sp。十一月 （Gymnodiniales，Dinophyceae），一种来自日本的混合营养性鞭毛藻的新物种

副伞菌属余谷口和H口sp。十一月 从日本宫城县Kitsunezaki收集的砂样品中分离出石蜡，并根据使用光，扫描和透射电子显微镜的观察结果以及分子分析进行了描述。池长9.4–17.1μm，宽5.7–13.6μm，表现为底栖生物。它们在附加体，眼点，线虫囊和多个叶绿体上分布着类囊体，具有沟延伸样的沟。他们通过吞食摄入了猎物细胞，表明营养是营养混合的。这些字符与属的已知物种共享Paragymnodinium，P. stigmaticum。但是，不同于P. stigmaticum，P。verecundum表现出趋光性阴性，并有脓包。线虫囊和鞭毛器的超微结构的其他差异表明这两个鞭毛鞭毛虫是不同的物种。基于级联18S和28S核糖体DNA序列的系统发生分析中回收P. verecundum中的物种的稳健进化枝Paragymnodinium内进化枝裸甲藻属狭义。姐姐到P. verecundum是P. stigmaticum，但他们清楚地分开。因此，该鞭毛藻被认为是副伞菌属的一个新物种。