The revision of specimens of the Cladonia pyxidata-chlorophaea group (lichenized Ascomycota) from northeastern Poland deposited in the herbarium collections of University in Bialystok

In northeastern Poland, the chemical variation of the Cladonia chlorophaea-pyxidata group was much neglected, as TLC has not been used in delimitation of species differing in the chemistry. As a great part of herbal material of University in Bialystok from NE Poland was misidentified, I found my studies to be necessary. Based on the collection of 123 specimens deposited in Herbarium of University in Bialystok, nine species of the C. pyxidata-chlorophaea group are reported from NE Poland. The morphology, secondary chemistry, and ecology of examined lichens are presented and the list of localities is provided. The results revealed that C. fimbriata is the most common species in the northeastern Poland, comprising around 33% of the studied specimens. Cladonia conista, C. cryptochlorophaea, and C. merochlorophaea are known only from very few locations. This study shed light on the role of the lichens substances to diagnosis of the species of C. pyxidatachlorophaea group.