Planothidium Haynaldii Guide
Credit: Marina Potapova
  1. Valves lanceolate to elliptic-lanceolate with capitate to subrostrate apices
  2. Valves 4.8-7.0 μm wide
  3. Rapheless valve with asymmetric central area containing rimmed depression

Valves are lanceolate to elliptic-lanceolate. Valve apices are capitate to subrostrate apices, 4.7-7 μm wide. The rapheless valve has an asymmetric central area containing a rimmed depression.