Halamphora Oligotraphenta Guide
Credit: Josh Stepanek
  1. Valve ends protracted capitate
  2. Dorsal striae punctate
  3. Proximal raphe ends widely spaced
  4. Striae 26-30 near middle, 32-34 near poles

Valves are semi-lanceolate and strongly dorsiventral. Valve ends are protracted and capitate.The proximal ends are widely spaced. The axial area is narrow throughout. Dorsal and ventral fascia are absent. Dorsal striae are punctate and radiate throughout. Ventral striae are continuous.