Guide to Navicula freesei
Credit: Paul Hamilton
- Valves strongly lanceolate
- Ends narrow, attenuated
- Central area asymmetric
- Axial area straight
- Striae irregularly spaced at center
Valves are strongly lanceolate, with narrow, attenuated ends. The asymmetric central area is distinct. Striae are linear and radiate at the center to weakly convergent at the apices. Striae are coarse and distinct; they are more widely spaced at the central area (5 in 10 µm) than the rest of the valve (8–10 in 10 µm). The proximal raphe ends expand into a rounded terminal pore.