Zeinab Shariatmadari - PhD Student/Faculty of Biosciences, Shahid Beheshti University, G. C. Tehran, Iran
Hossein Riahi - Professor/Faculty of Biosciences, Shahid Beheshti University, G. C. Tehran, Iran

In the study of the genus Cylindrospermum Kützing ex Bornet & Flahault (Nostocaceae) in terrestrial habitats, ۱۸ specimens belonging to eight species were identified. Specimens were collected from ۱۱ paddy field soils located in seven provinces of Iran. Five taxa, including Cylindrospermum sphaericum B. N. Prasad, Cylindrospermum catenatum (Ralfs) Bornet & Flahault, Cylindrospermum marchicum Lemmermann, Cylindrospermum minutissimum Collinsand Cylindrospermum muscicola Kützing ex Bornet & Flahault are considered as new records to Iran. An identification key, description and pictures of these species are presented in this study.

Cylindrospermum, morphospecies, new record, geographical distribution, Iran