Phylum: Charophyta   Family: Closteriaceae

Closterium boergesenii (W. Schmidle) P.F.M. Coesel & K.L. Meesters 2023

First described by Schmidle (1894: 50) as Closterium leibleinii f. boergesenii. Recently, it was raised to species level by Coesel & Meesters (2023: 46, pl. 15: 19).
Single cell dimensions: L: 169 µm; B: 32 µm; Ap: 3.4 µm; Arc: 172; L/B: 5.
A rare species that prefers circumneutral to slightly alkaline waters.

References: 
Coesel, P.F.M. & Meesters, K.J. (2023 second edition). Desmids of the Lowlands.
Schmidle, W. (1894). Algen aus dem Gebiete des Oberrheins.
Van Westen, M. (2024). Sieralgen in Drenthe.