Epilithic diatom diversity in Golestan waterfall

Waterfalls are considered as aquatic ecosystems, of which limited study was conducted on their biodiversity. Golestan waterfall is one of the outstanding waterfalls in eastern edge of Golestan National Park. Since no research was performed on algal flora in the area, the present study aimed to identify the epilithic diatoms of the waterfall, as a component of this ecosystem biodiversity. The samples were collected from stony substrates at each season. The results represented 24 genera including 47 species, which all taxa belonged to Bacillariophyceae. In addition, Cymbopleura with five species and Gomphonema, and Navicula with four species had more species, respectively. Further, Achnanthidium minutissimum, Amphipleura pellucida, Cymbella affinis, Cymbopleura kuelbsii, and Gomphonema pumilum were determined as the most abundant taxa. Furthermore, Delicatophycus verenae, Stauroneis separanda and Tryblionella brunoi were found in the diatom flora of Iran for the first time. Due to the few diatom studies in Iran, conducting detailed and local studies can improve data on diatom flora of Iran.