Description: The cells are (1.3)–1.4–1.6–(1.7) times longer than wide, broadly elliptical in shape. The lateral line of the shape showes soft ripples with horny ends. Cells are lightly tapered towards the rounded periphery with fine cuts in the middle and denticles on both sides. The incision in the middle of the cell (called sinus) runs deep and is straight-lined. At each center of the cell halves lies a thin swelling with a pattern of oblonged verrucae. Further nipples spread over the cell wall. Chloroplasts with few tiny pyrenoids.

Dimension: Length (23)–27–40 µm, width (14)–17–22–(26) µm.

Occurrence: Widely spread in acidic and middle acidic waters, in alpine regions up to altitude of 2000 m.

Left: Original graphic by Prof. Lenzenweger.
Right: Photomicrograph by Prof. Lenzenweger. For microphotography, the microscope illumination was adjusted in such a way that as many features as possible that are important for species identification are prominently displayed.

Copyright by Prof. Rupert Lenzenweger, Ried im Innkreis, Austria.