Navicula congqiancuoensis sp. nov. — a new diatom species (Bacillariophyceae) from Sichuan Province, China

In this study, we describe a new diatom, <i>Naviculacongqiancuoensis</i> <b>sp. nov.</b>, which was found in epilithon samples collected from a small mountain lake, at Lake Congqiancuo, Sichuan Province, China. A detailed morphological description of the new species is provided based on light and scanning electron micrographs. <i>Naviculacongqiancuoensis</i> <b>sp. nov.</b> valve is linear to linear-lanceolate, with a slight elevation in the center and broadly rounded at both apices. The striae are radiate and convergent at the apices. The axial area is narrow and linear, and the central area is small and elliptical in the middle. This new species is compared with similar species, such as <i>Naviculaangusta</i>, <i>N.leptostriata</i>, <i>N.piercei</i>, <i>N.heimansioides</i> which differ in size, valve shape, striae density and ultrastructure.