Tabellaria Guide
Credit: Sarah Spaulding
  1. Valve elongate, swollen in the middle, capitate
  2. Rimoportula present at midvalve
  3. Frustules with numerous copulae
  4. Cells form zig-zag colonies

Tabellaria valves are elongate with capitate ends. The valves are generally wider at the center than at the ends. A rimoportula is present in the center of the valve face. Septa are present on the numerous copulae (girdle bands). Pseudosepta may also be present. Cells form zig-zag colonies joined by mucilage pads secreted from apical porefields.

Tabellaria is considered a close relative of Oxyneis. The two genera share the presence of septa, which may be detached in some preparations. Species within the genus are found in a range of water types, from acidic to alkaline waters.