Cymbopleura stauroneiformis rev guide
  1. Valves lanceolate, dorsiventral
  2. Central area broad, nearly bow-tie shaped
  3. Proximal raphe ends deflected ventrally
  4. Terminal fissures curved dorsally

Valves are lanceolate, dorsiventral, and 6.5 to 11 µm wide. The central area is broad and often bow-tie shaped. The central area does not extend to the valve margin. Proximal raphe ends are deflected ventrally, while terminal fissures are curved toward the dorsal side.