Cyclotella Atomus Guide
  1. Off-center fultoportula
  2. Marginal fultoportulae every 4th-5th costa
  3. Valve surface flat

This taxon is a small diatom with marginal striae and a fultoportula near the valve center. The fultoportula appears as a dark spot. Marginal fultoportulae are present every 4th-5th costa.