A new species of Phormidium (Cyanobacteria, Oscillatoriales), Lake Tuz (Türkiye)

Some interesting Cyanobacteria (Oscillatoriales) samples adapted to the high salt environment were collected from shore of Lake Tuz (Central Anatolia, Türkiye). After detailed examination, it was determined that the samples belonged to the Phormidium genus, but had some differences in trichome structure and cell size. As a result of comparison with similar species of the genus, it was determined that these differences were of species-level importance. Based on morphological and ecological data, the Lake Tuz samples, which were decided to be a new species for the scientific world, were named Phormidium obaliae. The samples of the new species grow in regions with high saltwater, where seasonal streams flow into Lake Tuz. Phormidium obaliae is closely related to P. coricum and P. retzi. However, in P. obaliae, the apical cells are dome-shaped (not truncated), and the sheaths are thin and colorless (not thick and dark green to brown). The description of the new species, its comparison with similar taxa, informative photographs, and some of its ecological preferences are given in this study.