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 ┬Ám 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.