Oxytropis stukovii Palib. as the rare species of Oxytropis DC. of the Eastern Zabaikalye

The biomorphology and ontogenesis of the rare endemic species Oxytropis stukovii have been outlined and the onthogenetic structure of the population has been studied. The species ontogenesis includes 4 periods and 8 age stages. In our opinion, the factors limiting this species spreading are its steno- topic nature and also sharp fluctuations in quantity and ontogenetic structure of populations depending on climatic conditions within different years.