Genkalia Guide
Credit: Marina Potapova, Sarah Spaulding
  1. Valve outline linear to linear-elliptic or linear-lanceolate
  2. Valve face-mantle junction smooth
  3. Mantle deep
  4. Striae uniseriate
  5. Areolae round to elliptic

Genkalia was established in 2012 to accommodate Navicula digitulus and similar taxa. Valves are linear to linear-elliptic or linear-lanceolate in outline with rounded apices. The valve face-mantle junction is smooth and the mantle is deep. External proximal raphe ends are not expanded, but are often slightly curved towards primary valve side, or they may be straight. Terminal raphe fissures are long and broadly curved to the secondary side. Uniseriate striae continue uninterrupted from the valve face to the mantle. The striae are composed of round or elliptic, transapically elongated areolae.

Kulikovskiy et al. (2012) stated that areolae in Genkalia are unoccluded internally, while SEM images in Wojtal et al. (2014) show internal occlusions.

In North America, Genkalia species are common in high elevation lakes of the western US, including within Grand Teton National Park in Wyoming and Cascades National Park in Washington.