Desmid of the month
December 2022

Closterium juncidum

Like Closterium lineatum Cl. juncidum is characterized by elongate, but little curved cells marked by a finely striate cell wall. However, as compared to Cl. lineatum, cells of Cl. juncidum are smaller and provided with (true) girdle bands. Moreover, sexual reproduction in Cl. juncidum is by way of single, globose zygospores versus urn-shaped twin zygospores in Cl. lineatum. In the Netherlands, Cl. juncidum is of occasional occurrence in acidic bogs and moorland pools.

Closterium juncidum. Notice linear cell shape with truncate poles.
Cell dimensions (L x B): 200 x 9 µm

Cl. juncidum. Mid-region of empty cell showing striation of the wall.

Conjugated cells of Cl. juncidum wh globose zygospore in between.


Cl. juncidum. Detail of conjugated cells showing striate cell wall with girdle band.