New Data on Agaricoid and Gasteroid Agaricomycetes in Penza Region (Russia)

The study of agaricoid and gasteroid fungi belonging to the class Agaricomycetes in the Penza region has been carried out beginning with 1976. Due to significant changes in the taxonomy of this group in recent decades, it became necessary to revise the materials accumulated over a 46-year research period. As a result of such a revision, it was found that in the territory of the Penza region, were recorded 837 species of agaricoid and gasteroid fungi of the class Agaricomycetes. They belong to 8 orders, 39 families and 137 genera. The largest families, including more than 50 species, are Agaricaceae, Cortinariaceae, Psathyrellaceae, Russulaceae, Strophariaceae, Tricholomataceae, from 20 to 50 species – Boletaceae, Bolbiticaeae, Crepidotaceae, Entolomataceae, Hygrophoraceae, Marasmiaceae, and Mycenaceae. The remaining families include less than 20 species each. The first place in terms of species richness is occupied by the genus Cortinarius (109 species), the second by the genus Russula (60 species). The genera uniting from 30 to 60 species are Inocybe and Mycena, from 20 to 30 species – Agaricus, Entoloma, Lactarius, Lepiota, Psathyrella, and Tricholoma, from 10 to 20 species – Amanita, Clitocybe, Conocybe, Coprinopsis, Galerina, Hebeloma, Hygrocybe, Hygrophorus, Marasmius, Melanoleuca, Panaeolus, Pholiota. The remaining genera are characterized by lower species richness levels, although they make up 82% of the total species number. Of these, 41 genera include only one species. In the course of research carried out from 2018 to 2022, a total of 27 species of Agaricomycetes new to the region were found. Three of them, Russula groenlandica, R. insignis, and R. melzeri, were noted in Russia for the first time. At the same time, 20 previously discovered species were not confirmed as a result of our revision. During observations from 1976 to 2022, it was found that the number of some species of fungi in the group under consideration is not constant and is subject to changes in the long-term regime. For example, in Agaricus xanthodermus, Caloboletus radicans, Infundibulicybe geotropa, Lactarius semisanguifluus, Lepista personata, Mutinus ravenellii and Rubinoboletus rubinus, this number increases, whereas in Floccularia luteovirens, Lactarius turpis, Leucopaxillus tricolor, Russula chloroides, and Tylopilus felleus, on the contrary, it tends to decrease.