A diatom species is identified as Amphipleura pellucida (Kützing) Kützing during the study of diatom classification and diversity in the Wuling Mountains. The results demonstrate that A. pellucida possesses the following features: (1) spindleshaped valve outlines; (2) long and straight central sternum; (3) short raphe system only located next to two poles; (4) stria density 38-39/10 μm and areola density 54-58/10 μm; (5) external proximal raphe endings straight and distal raphe endings slightly dilated; (6) the internal areola openings occluding by hymenes. The results of this study provide clear ultrastructure pictures and scientific descriptions for A. pellucida.