A new Pseudostaurosira species (Bacillariophyta, Staurosiraceae) from lowland rivers and lakes in Europe (Atlantic Biogeographic Region)

During a biomonitoring survey of the Flemish rivers, an unknown Pseudostaurosira taxon was observed. After detailed light and scanning electron microscopy research and careful analysis with similar species in literature, the taxon is described as Pseudostaurosira katharinae sp. nov. The new species can be separated from similar Pseudostaurosira species by its larger sternum and central area, the presence of rings of granules around the spines, the shape and diminishing size of the areolae towards the center and the particular structure of the cingulum. The new species was typically found in meso-eutrophic, alkaline conditions.