The genus Paragymnodinium currently includes two species, P. shiwhaense and P. stigmaticum, that are characterized by mixotrophic nutrition and the possession of nematocysts. In this study, two new dinoflagellates belonging to this genus were described based on observations using LM, SEM, and TEM together with a molecular analysis. Cells of P. asymmetricum sp. nov., isolated from Nha Trang Beach, Vietnam, were 7.9–12.6 μm long and 4.7–9.0 μm wide. The species showed no evidence of feeding behavior and was able to sustain itself phototrophically. Paragymnodinium asymmetricum shared many features with P. shiwhaense, including presence of nematocysts, absence of an eyespot, and a planktonic lifestyle, but was clearly distinguished by the asymmetric shape of the hyposome, possession of a single chloroplast, and its nutritional mode. Cells of P. inerme sp. nov., isolated from Jogashima, Kanagawa Pref, Japan, were 15.3–23.7 μm long and 10.9–19.6 μm wide. This species also showed no evidence of feeding behavior. Paragymnodinium inerme was similar to cells of P. shiwhaense in shape and planktonic lifestyle, but its nutritional mode was different. The presence of incomplete nematocysts was also a unique feature. A phylogenetic analysis inferred from concatenated SSU and LSU rDNA sequences recovered the two dinoflagellates in a robust clade with Paragymnodinium spp., within the clade of Gymnodinium sensu stricto. This evidence, together with their morphological similarities, made it reasonable to conclude that these two dinoflagellates are new species of Paragymnodinium.

中文翻译：

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鞭毛藻的两个新种，不对称副伞菌属的超微结构和系统学。十一月 和Paragymnodinium Inerme sp。十一月 （地龙科）1。

副伞菌属（Paragymnodinium）目前包括P. shiwhaense和P. stigmaticum这两个物种，其特征是混合营养和拥有线虫囊。在这项研究中，基于使用LM，SEM和TEM进行的观察以及分子分析，描述了两个属于该属的新鞭毛虫。不对称假单胞菌的细胞。nov。，与越南芽庄海滩隔离，长7.9–12.6μm，宽4.7–9.0μm。该物种没有任何摄食行为的证据，并且能够自我维持营养。不对称副伞花草与P. shiwhaense共享许多特征，包括存在线虫囊，不存在眼点和浮游生活方式，但明显区别在于次体的不对称形状，单个叶绿体及其营养模式。P. inerme sp。的细胞 nov。分离自日本神奈川县Jogashima，长15.3-23.7μm，宽10.9-19.6μm。该物种也没有显示进食行为的证据。副羊膜藻的形状和浮游生活方式与波氏假单胞菌的细胞相似，但其营养方式不同。不完整的线虫囊的存在也是一个独特的特征。从串联的SSU和LSU rDNA序列推论出的系统发育分析，在带有伞草odi虫的稳健进化枝中回收了两个鞭毛虫。spp。，在Gymnodinium sensustricto进化枝内。这一证据及其形态相似性使我们有理由得出以下结论：这两个鞭毛虫是副gy虫的新种。