Chlorostroma vestlandicum (Xylariales): first records of the rare ascomycete in Russia

In this paper, for the first time in Russia we report on four new occurrences of the rare xylarialean ascomycete Chlorostroma vestlandicumrevealed in the course of mycological surveys of the Northwestern European Russia. Description and colour illustrations of the material studied are provided. Dutch Elm Disease as the major possible threat for the species is discussed. The species is recommended for inclusion in the next editions of the regional Red Data Books of Leningrad, Novgorod, and Pskov Regions.