The article provides information about the distribution and state of local populations in the Leningrad Region and the Republic of Karelia of a rare fungus Sarcosoma globosum (Schmidel) Casp. listed in the Red Data Book of the Russian Federation. Data on a number of new localities of the species are presented, including information on the occurrence of S. globosum in the eastern part of the Leningrad Region and on islands in the Gulf of Finland, where the fungus has been recorded for the first time. The authors’ own field surveys show
that within the regions in question the species is mainly associated with little disturbed mediumaged spruce and spruce-small-leaved forests (less often with old-growth communities) on well-moistened and relatively nutrient-rich soils. In the surveys, the number of fruit bodies in the local populations of S. globosum varied from single fruit bodies to 120–200. Phenological patterns were noted for the species in the Leningrad Region and Karelia: a majority of the findings were made from April to June, but in years with long and warm autumn periods fruit bodies were found to develop also in November and December. Alteration of the species distribution and increase in the number of localities with S. globosum are probably associated with climate change: the authors, in agreement with Finnish researchers, attribute a noticeable “upsurge” of new findings of the species in the Leningrad Region and Karelia in recent years to a decrease in the number of long, severe winters. The recommended measures for the species protection include establishment of protected areas in the places of its growth as well as inclusion of S. globosum in the Red Data Book of the Republic of Karelia.