A New Record of the Genus Onopordum from Asteraceae for the Flora of Iran

 Onopordum is one of the extremely armed genus of the family of Asteraceae which is native to the Mediterranean and Irano-Turanian regions. This genus comprises 7 species that are distributed in most parts of the country. In spite of 12% of Onopordum species are found in Iran, but few taxonomic studies have been carried out and it seems that there are still unknown species of this genus. For taxonomic study of the genus Onopordum, extensive collection of distribution areas of genus was conducted in Iran. Plant specimens were collected by conventional methods and identified based on reliable sources. As a observations, O. cinereum is reported as a new record from the flora of Iran. It is easily distinguished form the other species of genus in Iran by having densely tomentose-arachnoid-whitish indumentum in throughout the plant especially in the capitula. Finally, a key identification to all species of the genus Onopordum in Iran is presented.