Image © Alfred van Geest
Closterium calosporum. Notice evenly curved cell with smooth wall.
Cell dimensions (L x B): 135 x 12 µm
Cl. calosporum belongs to the large group of Closterium species characterized by a smooth cell wall without any girdle bands. Cells of Closterium calosporum are evenly curved and gradually taper from the middle to the poles. The apices are obliquely truncate, usually with a marked end-pore. Vegetative cells may be confused with those of some other species (in particular Cl. dianae) but its zygospore is most distinctive as it is provided with conical projections whereas zygospores of most other Closterium species are smooth-walled.
Image © Marien van Westen
Another cell of Cl. calosporum showing obliquely truncate apices provided with an end-pore.
Image © Alfred van Geest
Conjugated cells of Cl. calosporum with a zygospore in between.
Image © Alfred van Geest
Cl. calosporum, detail of zygospore. Notice conical projections.