Delicata Montana Guide2
  1. Valves rhombic-lanceolate
  2. Valves weakly dorsiventral
  3. Dorsal striae slightly shorter at valve center
  4. Apices broadly rounded

Valves are rhombic-lanceolate and weakly dorsiventral. Dorsal striae at the valve center are slightly shorter and sometimes irregularly spaced. Striae are more widely spaced near the valve center than at the apices. The apices are broadly rounded rather than protracted.