Population of Calypso bulbosa (Orchidaceae) at the northern part of its distribution range (Belomor-Kuloy plateau, river Polta basin)

The structure of the large population (265 ind.) of the rare taiga orchid species Calypso bulbosa in the basin of River Polta (Starokoleynaya Riv.) was studied for the first time. Morphometric variations inside the population was recoded. The comparison with the plants from other areas of the distribution revealed a high similarity in morphology on different stages of ontogeny. The morphological parameters Starokoleynaya Riv. population plants are similar to the parameters of plants Khibiny and the Ural population. The population has right-handed age spectrum. It consists of 77% of adult vegetative and generative individuals.