Prasiola calophylla and Closterium navicula, two new records of algal flora from Iran

Two new algal species, namely, Prasiola calophylla (Prasiolaceae), and Closterium navicula (Closteriaceae) were collected from west coasts of the Caspian sea (Mazandaran province, N Iran), and runoff in south Tehran, respectively. Both the species were analyzed on the bases of morphological and anatomical characters and were determined using identification keys and interspecific comparison. Prasiola calophylla had a length of 1–2 cm and a width of 2–3 mm. It was found in three forms of membranous, uniseriate and biseriate filaments. Cells were quadrate, polygonal and rarely rectangular. The ribbon-like thallus, the disk-like rhizoid, stipe and blade, central chloroplast, one or two pyrenoids in each cell, and anticlinal and periclinal cell divisions were other characteristics of this species. Closterium navicula had an average dimension of 12 × 57 μm. Cells were straight and fusiformwith raphe groove prominence, rounded-truncated pole, and had polar vacuoles. Both species are introduced in Iran for the first time.