Abstract
This study describes a new species of Pinnularia, P.hupingensissp. nov., on the basis of light and scanning electron microscope images. Pinnulariahupingensissp. nov. is characterised by its linear valve outline, extremely divergent striae, and very large hexagonal central area occupying ca. 1/5-1/8 of the valve length. The primary and secondary sides of the valve and the internal proximal raphe fissures are discussed. The new species is compared to similar taxa of the genus Pinnularia.