Eunotia panda

Valves are arcuate, isopolar, having a curvature of 0.74–1.00 radians, with a slight increase in curvature from the largest to the smallest valves (Figs 56–86), with length to breadth ratio 12–27:1, 33–97 μm long, 3–4 μm wide (mostly 3.5 μm). Ventral and dorsal valve margins are parallel through most of the valve, only tapering very near the apices, slightly reflexed dorsally at the weakly protracted ends (Figs 56–87). Valve apices bear many minute, sharp siliceous protrusions, which are situated irregularly between the striae or areolae (Figs 88, 90, 93, 95). Valve margins are typically sharply beveled with a single row (rarely double rows) of areolae in the beveled portion (Fig. 89). In LM the raphe is distinct, but short. It begins on the valve mantle (Fig. 92), and curves subapically on the valve face back towards the main part of the valve (Figs 87–93, 95) as visible from SEM. The raphe is centered in the apical region, with external fissures visible on the external portion of the valve (e.g., Figs 88, 95), but not penetrating the internal part of valve past the helictoglossa (Figs 96–103). Helictoglossa is visible in the LM (Figs 56–86). A single rimoportula, placed at the apex, is present per valve (Figs 96–103). Striae are lowered in between hyaline ridges, parallel in the center of the valve, radiating towards the apices (Figs 56–93), 14.5–17(20) in 10 μm in the center valve, up to 21 in 10 μm near the apices. Areolae are open, rounded with irregular edges or irregular in shape (Figs 88–90, 92–95, 98, 99, 101, 102), 33–40 in 10 μm.

• Author
  J.Veselá and J.R.Johans. 2014
• Length Range
  33–97 µm
• Width
  3–4 µm
• Striae in 10µm
  14.5–17 (up to 21 near the apices)