Proschkinia Browderiana Guide2
  1. 2-4 nearly parallel striae at mid-valve
  2. Valve lanceolate
  3. Striae convergent near apices (SEM)
  4. Fistula not reaching axial rib (SEM)

Only the middle 2-4 striae can be resolved using light microscopy. Striae near the apices are not visible. The valves are lanceolate and often have protracted or rostrate apices. The striae are convergent near the apices (SEM). The internal opening of the fistula is located a short distance from the axial rib, but requires SEM to resolve.