Diversity and environmental characterization of Agaricales fungi in a young Tessaria integrifolia Ruiz & Pav. forest

It is estimated that there are between 2.2 and 3.8 million species of fungi, but only 3 to 8% are known. The order Agaricales in Argentina is not well known in certain areas and plant communities, as the Reserva Ecológica Costanera Sur (RECS), with a younger than 40 years Tessaria integrifolia Ruiz & Pav. riparian forest, characterized by a humid climate. The objective of this work was to document the diversity of Agaricales in the young forest of the RECS and analyze its diversity in relation to environmental characteristics. Sixteen rectangular plots were established and fungal species were collected monthly for one-year analyzing their macro- and microscopic structures. A total of 48 species belonging to 15 families were recorded with Inocybaceae Jülich, Pluteaceae Kotl. & Pouzar, and Psathyrellaceae Vilgalys, Moncalvo & Redhead being the most represented. Abundance, measured by the number of basidiomes, and dry weight, were 8 351 and 661.6 grams, respectively. The pH in the study plots was in general neutral and the light ranged from 101 to 48 056 lux. May exhibited the highest basidiome production and species richness. Three species were found for the first time in the area, which had previously been found in latitudes with a subtropical climate several years ago, potentially indicating climatic changes. Substrate type influenced the diversity, with wood being the preferred substrate for most species. This research contributes to the knowledge of Agaricales diversity in a young protected forest area and emphasizes their role in soil nutrient cycling and biodiversity maintenance.