Simple filamentous cyanobacteria comprise a diverse and polyphyletic group of species, primarily in the orders Leptolyngbyales and Oscillatoriales, that need more sampling to improve their taxonomy. Oceanic islands, such as the Azores archipelago, present unique habitats and biogeographic conditions that harbor an unknown range of diversity of microorganisms. Filamentous cyanobacteria isolated from aquatic habitats in the Azores and maintained in the BACA culture collection were described using morphology, both light and transmission electron microscopy, ecology, and genetic data of the 16S rRNA gene sequences and 16S–23S Internal Transcribed Spacer (ITS) rRNA region secondary structure. Our analyses revealed two new monophyletic genera: Tumidithrix elongata gen. sp. nov. (Pseudanabaenaceae) and Radiculonema aquaticum gen. sp. nov. (Leptolyngbyaceae). In addition, two new species Leptodesmis lacustris sp. nov. (Leptolyngbyaceae) and Pycnacronema lacustrum sp. nov. (Wilmottiaceae) are reported as the first aquatic species for these genera. The description of these new taxa and the genetic study of an isolate of Leptodesmis alaskaensis from the Azores followed the polyphasic approach, identifying diacritical features. Our results reinforce the need for taxonomic studies on cyanobacteria from less-studied habits and geographic regions, which have a potential for new taxa description.

中文翻译：

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亚速尔群岛淡水栖息地的四种新丝状蓝藻类群的描述

简单的丝状蓝细菌由一个多样化的多系物种组成，主要是 Leptolyngbyales 和 Oscillatoriales 目，需要更多的采样来改进其分类。亚速尔群岛等海洋岛屿拥有独特的栖息地和生物地理条件，蕴藏着未知的微生物多样性。使用形态学、光学和透射电子显微镜、生态学以及 16S rRNA 基因序列和 16S–23S 内部转录间隔区 (ITS) rRNA 的遗传数据描述了从亚速尔群岛水生栖息地分离并保存在 BACA 培养物保藏中心的丝状蓝藻。区域二级结构。我们的分析揭示了两个新的单系属：Tumidithrix elongata gen。sp。十一月 （Pseudanabaenaceae）和Radiculonema Aquarium gen。sp。十一月 （Leptolyngbyaceae）。此外，还有两个新种Leptodesmis lacustris sp。十一月 （Leptolyngbyaceae）和Pycnacronema lacustrum sp。十一月 据报道，（Wilmottiaceae）是这些属的第一个水生物种。这些新类群的描述以及来自亚速尔群岛的阿拉斯加细线虫分离株的遗传研究遵循多相方法，识别变音特征。我们的结果强调了对来自较少研究的习性和地理区域的蓝藻进行分类学研究的必要性，这些蓝藻有可能进行新的分类群描述。