DISTRIBUTION PATTERNS OF THE GENUS COUSINIA (ASTERACEAE) IN IRAN

The geographical distribution of the genus Cousinia in Iran has been analyzed using a dataset of 3095 georeferenced observations. The 241 species of the genus are distributed throughout Iran. However, about third of the observations are made from provinces like, Khorasan Razavi, Tehran, and Fars. The genus has 135 rare species and 197 endemic species. The maximum distance between two observations of the same species, (MaxD) is 1863 kilometers. Razavi Khorasan, Lorestan, Esfahan, North Khorasan and Tehran have the highest number of rare species. Species richness was mapped with the point-to-grid richness analysis tool DIVA-GIS, using a 10×10 kilometer grid cell and the circular neighborhood option with a 50 km radius. High species richness occurs in large area in North of Semnan province, Dena Mountains, Central Alborz, Lorestan province, NW Iran and also in Kopet Dagh Mountain in Khorasan where the hotspots for endemic species are located. Forty five 0.5o×0.5o grid cells are needed to capture all species at once, which have the most conservative importance for this group of plants