review of four genera of calcareous algae from upper triassic bidestan and howz-e khan members of the nayband formation (southeastern nayband mount)

for the study of upper triassic calcareous algae, four sections from the bidestan and howz-e khan members of the nayband formation, exposed in the southeast area of the nayband mountain were measured and sampled. to obtain the variation of algae, additional scattered samples were collected from this region. algal carbonate layer, rich of dasycladales was recovered in the howz-e khan member. after the laboratory and microscopic investigations, four genera and four species of calcareous algae, including griphoporella curvata (gümbel), chinianella carpatica (bystrický), diplopora interiecta fenninger and acicularia antique pia.have been recognized.