Closterium angustatum var. angustatum
Closterium angustatum var. boergesenii
Closterium angustatum var. annulatum
Closterium angustatum var. gracile
Closterium angustatum var. rectum
Closterium angustatum f. elongatum
Closterium angustatum f. boergesenii
Closterium angustatum var. asperum
Closterium angustatum var. clavatum
Closterium angustatum var. gracilius
Closterium angustatum f. multistriatum
Closterium angustatum var. sculptum
Closterium angustatum var. pseudoboergesenii
Closterium angustatum var. reticulatum
Closterium angustatum var. subclavatum
Closterium angustatum var. subrecta
Closterium angustatum f. tenuis