Thainema gen. nov. (Leptolyngbyaceae, Synechococcales): a new genus of simple trichal cyanobacteria isolated from a solar saltern environment in Thailand

Simple trichal types constitute a group of cyanobacteria with an abundance of novel, often cryptic taxa. Here, we investigated material collected from wet surface-soil in a saline environment in Petchaburi Province, central Thailand. A morphological comparison of the isolated strain with similar known species, as well as its phylogenetic and species delimitation analyses based on the combined datasets of other related organisms, especially simple trichal cyanobacteria, revealed that the material of this study represented an independent taxon. Using a multifaceted method, we propose that this material represents a new genus, Thainema gen. nov., belonging to the family Leptolyngbyaceae, with the type species Thainema salinarum sp. nov. This novel taxon shares similar ecological habitats with strains previously placed in the same lineage.

简单丝状体蓝细菌类群（simple trichal cyanobacteria）是一类蕴含大量新颖且多为隐存分类单元的蓝细菌。本研究对采自泰国中部碧武里省（Petchaburi Province）盐生环境的湿润表层土壤样本开展了研究。通过将分离获得的菌株与已知近缘物种进行形态学比对，并基于其他相关类群（尤其是简单丝状体蓝细菌）的联合数据集开展系统发育分析与物种界定研究，结果表明本研究样本代表一个独立的分类单元。本研究采用多维度研究方法，提出该样本隶属于细鞘丝藻科（Leptolyngbyaceae）下的新属——泰蓝丝菌新属（Thainema gen. nov.），其模式种为盐生泰蓝丝菌（Thainema salinarum sp. nov.）。该新颖分类单元与此前归属于同一演化支的菌株具有相似的生态栖息生境。