Song Huiyin, Wang Qinghua, Liu Xudong, Hu Yuxin, Long Jijian, Liu Guoxiang, Hu Zhengyu
Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China.
University of Chinese Academy of Sciences, Beijing, 100039, China.
J Eukaryot Microbiol. 2018 May;65(3):382-391. doi: 10.1111/jeu.12482. Epub 2017 Nov 16.
The Parachlorella clade was put forward as a group within the family Chlorellaceae in 2004. Recent molecular analyses have revealed that Dictyosphaerium morphotype algae form several independent lineages within the Parachlorella clade, and new genera and species have been established. In this study, we focus on the diversity of Dictyosphaerium morphotype algae within the Parachlorella clade, based on 42 strains from China. We used combined analyses of morphology and molecular data based on SSU and internal transcribed spacer region (ITS) rDNA sequences to characterize these algae. In addition, the secondary structure of ITS2 was compared to delineate new lineages. Our results revealed high phylogenic diversity of Dictyosphaerium morphotype algae, and we describe five distinct lineages. We examined the morphological features of these five lineages, and morphological differences are difficult to find compared with other Dictyosphaerium morphotype algae. The five distinct lineages were not described as new genera currently. We lastly discuss the taxonomic problems regarding the Dictyosphaerium morphotype within the Parachlorella clade, and possible solutions are considered.
小球藻分支在2004年被提出作为小球藻科内的一个类群。最近的分子分析表明，盘星藻形态型藻类在小球藻分支内形成了几个独立的谱系，并且已经建立了新的属和种。在本研究中，我们基于来自中国的42个菌株，聚焦于小球藻分支内盘星藻形态型藻类的多样性。我们使用基于小亚基（SSU）和内转录间隔区（ITS）核糖体DNA序列的形态学和分子数据的联合分析来表征这些藻类。此外，还比较了ITS2的二级结构以划分新的谱系。我们的结果揭示了盘星藻形态型藻类的高度系统发育多样性，并且我们描述了五个不同的谱系。我们研究了这五个谱系的形态特征，与其他盘星藻形态型藻类相比，形态差异很难找到。这五个不同的谱系目前未被描述为新属。我们最后讨论了小球藻分支内盘星藻形态型的分类学问题，并考虑了可能的解决方案。
