Ali Asghar Maassoumi - Botany Research Division, Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), P. O. BOX ۱۳۱۸۵-۱۱۶, Tehran, Iran.
Mohammad Mahmoodi - Botany Research Division, Research Institute of Forests and Rangelands, Agricultural Research, Education and Extension Organization (AREEO), P. O. BOX ۱۳۱۸۵-۱۱۶, Tehran, Iran.
Ali Bagheri - Department of Plant and Animal Biology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan, Iran.

Based on morphological and molecular phylogenetic data, here we describe Astragalus sect. Irania Maassoumi, Mahmoodi & Bagheri as a new section in the immense genus Astragalus. Description and diagnosis are given. Morphologically, the new section is closely related to sect. Stereothrix Bunge, which is widely, distributed in Elburz and Zagros Mountains ranges. The new section differs from sect. Stereothrix in characters of the inflorescence, color of petals and stipules. But in the molecular phylogenetic analysis, it is surprisingly placed among the thorny Astragalus species. Type of the new section is A. issatissensis Maassoumi, Mahmoodi, which is so far known only from the highest elevations of Shirkuh Mt. above ۳۸۰۰ m a.s.l in Yazd province.

new section, Astragalus issatissensis, Shirkuh, Alpine, Yazd, Iran