Navicula sovereignii is distinguished by the vermiform markings on the axial and central areas, bulbous and laterally expanded proximal raphe ends, and a round central area. Navicula aurora has triangular proximal raphe ends and a transversely rectangular central area. Navicula reinhardtii has small bulbous proximal raphe ends, a narrow transverse central area, and coarser areolae in the striae. Navicula oblonga has linear valves, simple, undifferentiated proximal raphe ends and bent terminal striae.