Image © Marien van Westen
Closterium praelongum. Notice slender cell with cylindrical midregion and gradually attenuated ends.
Cell dimensions (L x B): ca 250 x 11 µm
Closterium praelongum is a rather large-sized species. Cells are slender, in their midregion almost straight and cylindric, towards the ends slightly curved and gradually attenuated. Most characteristic are the slightly recurved cell ends. Cell wall is seemingly smooth. but may show a delicate sculpture of punctae or short striae as well. In the Netherlands, Cl. praelongum is of occasional occurrence in various meso-eutrophic waters.
Image © Alfred van Geest
Cl. praelongum. A couple of semicells showing recurved cell ends.
Image © Alfred van Geest
Cl. praelongum. Detail of cell apex showing vacuole with many small crystals.