زینب شریعتمداری - Ph.D. student, Faculty of Biosciences, Shahid Beheshti University, G.C., Tehran, Iran
حسین ریاحی - Prof., Faculty of Biosciences, Shahid Beheshti University, G.C., Tehran, Iran (E-mail: h-riahi@cc.sbu.ac.ir)

Four paddy fields in Guilan province in the north of Iran seasonally were sampled from April ۲۰۰۸ to January ۲۰۰۹. Twenty-two morphospecies belonging to three families of the heterocystous blue-green algae were identified. Fourteen species and one variety of these taxa are new record for Iran. Among the families Nostocaceae with six genera and ۱۶ species showed the highest species richness.

Blue-green algae, identification, morpho-species, Iran