Onosma moussavi sp. nov (Boraginaceae) from Zagros Mountain (s), Iran

During field excursions in Western districts of Iran, an unknown species of Onosma was collected in eroded slopes in steppe formations near the border of Iran and Turkey. A detailed assessment on the basis the most important diagnostic characters as well as literature review led to introduce a new species of Onosma L.. The new species Onosma moussavi Mehrabian & Amini Rad is described and illustrated based on comprehensive literature review as well the study of type specimens of several other taxa in Iranian and European herbaria. The reason for this innovation is the author's evaluation on the basis of obvious differences in the most important diagnostic characters compared to their nearest taxa.