So far, I have only found Ankistrodesmus arcuatus in the pond of the convent Hegne, where the species is, however, rare. Due to its slender and strongly curved shape, the alga is easy to recognize. There is only one chloroplast present, which lies against the convex side of the cell (s. fig. 3 b). In the middle of the concave side is the very small nucleus, which is often located in an indentation of the chloroplast (s. fig. 3 a). After cell division, the daughter cells remain connected by their concave sides before these aggregates later break down into individual cells (s. fig. 1 a).