Prestauroneis dayaensis—a new diatom species (Bacillariophyceae: Stauroneidaceae) from Guangdong Province, China

In this study, we describe a new diatom, Prestauroneis dayaensis sp. nov., found in a coastal river, Danao River, at Daya Bay, Huizhou City, Guangdong Province, China. A detailed morphological description of the new species is provided based on light and scanning electron microscopy. P. dayaensis sp. nov, has an elliptical to lanceolate-elliptical valve outline with distinctive rostrate to subcapitate apices, the raphe straight, and the proximal raphe ends slightly enlarged toward to the same side. Its areolar structure is variable in shape, circular at the central area, linear to elliptic at the ends, and distinct pseudosepta present at both apices. Length 25.5–32.0 μm, width 8.0–11.5 μm. This axial area is narrow and linear. The central area is nearly rectangular, some with one short stria at one side of the valve. Striae are relatively widely spaced and radiate at the center, becoming nearly parallel at both apices. The new species is compared with species from the genus Prestauroneis and Dorofeyukea.