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In this study Astragalus L. with bifurcating hairs in sectional levels in Iran are discussed (subgenus Cercidothrix Bunge). This subgenus has more than 800 species in the Old World. Major areas of species endemism for this subgenus occur in Turkey, Iran, Kazakhstan and Afghanistan. Iran, with 158 species, is one of the most important centres of diversity. Leucocercis Bunge is the only endemic section for Iran, although other sections have some species in different countries. Thus having a knowledge of the distribution quality in other areas is also important. In reality, this study is part of the authors research on bifurcating Astragalus in the whole of the Old World. In this article, the most important characteristics for the separation of the sections, the relationships between the sections and an identification key for the sections in Iran are presented. For each section a distribution map is provided. [ABSTRACT FROM AUTHOR]

Abstract: A network of continuous GPS stations has been installed in NW Iran since 2005 to complement the survey GPS network already existing in the region. We present the 1999–2009 GPS-derived velocity field for this region based on the continuous and survey-mode observations. The results confirm a right lateral slip of 7±1mm/yr for the North Tabriz fault, in agreement with previous studies. This rate is consistent with earthquakes of magnitude 7–7.3 and recurrence times of 250–300yr. The higher spatial coverage of the new network shows that deformation is localized in the vicinity of the Chalderan, south Gailatu-Siah Cheshmeh-Khoy fault and the North Tabriz fault. However the eastern end of the North Tabriz fault appears to cross Mount Bozgush rather than following its southern foothills. This new velocity field does not indicate the 8mm/yr of NNE–SSW extension suggested earlier for the region, but rather shows lower extension of 1–2±1mm/yr across the eastern segment of the North Tabriz fault and the Talesh. To the west, the Chalderan and the western North Tabriz fault segment act like pure strike slip faults without significant extension or compression. The denser network in the Rudbar earthquake region (Ms 7.3, 1992) shows no significant motion across the fault, suggesting that the recurrence time of earthquakes like the Rudbar event must be very long. The lack of substantial compressive strain and the sharp azimuth change of the velocity vectors in the transition zone from Arabia to Lesser Caucasus motion imply that processes other than “extrusion”, possibly related to old subduction or delamination, contribute to active deformation. [Copyright &y& Elsevier]