Frontiers of Biogeography

Approximately 3,800 species of vascular plant species have been registered in the flora of Armenia, of which chromosome numbers are known for 798. Additionally, many species have several cytoraces in Armenia (a total of 904 cytoraces have been recorded). The main goal of the study was to elucidate some specific features of florogenesis on the basis of karyological data, and the aim is to characterize the distributions of the cytoraces across floristic regions of Armenia, including elevational zones, and habitats. The study is underpinned by results of our long-term study of Armenian flora, which entailed comprehensively characterizing their chromosome numbers and karyotypes. Geographical elements were established based on general distribution. As a result of the analysis, it was found that the Armenian flora was formed over a long period, starting from the Paleocene period, and is composed of nearly equal proportions of migrants from the Boreal and Ancient Mediterranean subkingdoms, and species that evolved in the Armenian Highlands and in the Greater Caucasus. The possession of a significant percentage of endemics (mainly neoendemics) indicates that the territory of Armenia is also an arena of intensive formation and speciation. In addition, we also illuminated a large karyological diversity among species whose distribution is confined to the Ancient Mediterranean subkingdom or its parts, including the Armeno-Iranian province; this is indicative of speciation having occurred in these territories. The “northern root” species, Boreal and Caucasian, became establish in Armenia mainly in the form of karyologically stable cytoraces.