Guide to Nitzschia
Credit: Marina Potapova, Sarah Hamsher, Sarah Spaulding
- Raphe eccentric, within a keel
- Keel supported by internal fibulae
- Raphe of each valve on opposite sides of the frustule
The nitzschioid raphe is positioned eccentrically within a keel which is supported by fibulae. Valves lack a sternum. Within the genus, species have a large range in size, from very small to very large.
Nitzschia is a very common genus with a large number of species that are often difficult to identify. Some Nitzschia species reach great abundance in waters high in organic pollution.