PDF(Pubmed)
Abstract：
Stauroneis (Naviculales, Bacillariaceae) are widespread, mostly in fresh-water habitats, and account for 343 species. They are described mainly on the basis of morphology and morphometric traits. These characteristics vary during life cycles and may overlap between species, making their identification difficult. We isolated two strains of naviculoid diatoms and examined them using an integrative approach (phylogenetic, morphological, ultrastructural data, and life cycle). Phylogenetic analyses based on chloroplast rbcL gene data showed affinity of the new strains to the genus Stauroneis. Our algae share morphological features typical of Stauroneis but differ from similar species in minimal valve length measurements, valve apex shape, and minimal number of striae in 10 μm. Two strains are distinct from each other in maximal valve length and width, partially valve shape, the number of areolae in 10 μm, and cingulum structure. It was revealed that the strains reproduce via isogamy. Three species delimitation methods (ASAP, PTP, and GMYC) also confirmed that the two closely related new strains represent distinct species. Based on molecular data and phenotypic traits examined within the framework of an integrative approach, we describe two new isolates as Stauroneis urbani sp. nov. and Stauroneis edaphica sp. nov.
摘要：
Stauroneis（Naviculales，芽孢杆菌科）很普遍，主要在淡水栖息地，占343种。主要根据形态和形态特征对它们进行描述。这些特征在生命周期中有所不同，并且可能在物种之间重叠，使他们难以识别。我们分离了两株naviculoid硅藻，并使用综合方法对其进行了检查（系统发育，形态学,超微结构数据，和生命周期)。基于叶绿体rbcL基因数据的系统发育分析显示，新菌株与Stauroneis属的亲和力。我们的藻类具有Stauroneis的典型形态特征，但在最小瓣膜长度测量方面与相似物种不同，瓣膜顶点形状，和10μm的最小条纹数。两个应变在最大瓣膜长度和宽度上彼此不同，部分瓣膜形状，10μm的乳晕数，和扣带结构。结果表明，该菌株通过同种关系繁殖。三种物种划界方法(ASAP，PTP,和GMYC）也证实了这两个密切相关的新菌株代表不同的物种。根据在综合方法框架内检查的分子数据和表型性状，我们将两个新的分离株描述为Stauroneisurbanisp。11月。和Stauroneisedaphicasp。11月。
