Morphometric parameters (plant height, number, length and width of vegetative and generative organs) of living specimens of the rare endemic plant Oxytropis popoviana Peschkova from reference natural populations of the northwestern coast of Lake Baikal were studied for the first time. The variability of various signs has been studied. The obtained morphometric parameters of O. popoviana were compared with those given in the protologue of this species and with the parameters of the closely related species Oxytropis grandiflora (Pall.) DC. The study of the variability of signs for use in diagnostics showed that the most stable parameters of the flower are: the length and width of the flag, the length and width of the boat, the length and width of the cup, the length of the wings. The length and width of the beans also change little. The lengths of the tip of the boat and the bean, as well as the signs of the leaves, are the most variable. A comparison of the morphometric parameters of O. popoviana obtained by us with the values indicated in the O. popoviana protologue, as well as with the data for O. grandiflora, showed the uniqueness of O. popoviana plants in the natural populations of Rytiy and Pokoyniki capes. According to the signs of the vegetative sphere, they approach O. grandiflora, and according to most quantitative and qualitative generative signs they correspond to the parameters of O. popoviana indicated in the protologue, or approach them.

Stepantsova N.V. Morphometric Parameters of Oxytropis popoviana Peschkova from Natural Populations of the Northwestern Coast of Lake Baikal (Irkutsk Region, East Siberia). The Bulletin of Irkutsk State University. Series Biology. Ecology, 2024, vol. 47, pp. 15-26. https://doi.org/10.26516/2073-3372.2024.47.15 (in Russian)

Oxytropis popoviana, northwest coast of Lake Baikal, reference populations, morphometric parameters, variability of features.

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