Guide to Fistulifera

The frustules of Fistulifera are very lightly silicified. Valves range in shape from linear to elliptical. Cells are small (usually < 8 µm) and possess numerous thin girdle bands, up to fourteen or more. Striae are not visible with light microscopy. The central sternum is distinct and may remain in a sample after the thin frustule has been destroyed in standard preparation.

Fistulifera includes the former Navicula pelliculosa (Bréb.) Hilse and N. saprophila Lange-Bert. These species grow in a wide range of freshwaters and they may be often overlooked because of their small size and light silicification. Fistulifera can reach high abundance in eutrophic and polluted waters.