N Recens Guide
Credit: Marina Potapova
  1. Valve lanceolate with blunt, subrostrate ends
  2. Central area round to transversely rectangular
  3. Proximal raphe ends straight

Valve lanceolate with blunt, subrostrate ends. The central area is variable in shape, from circular to transversely rectangular. The raphe is straight, as are the proximal raphe ends.