Agaricus section Minores: a new species to science, and six species recorded for the first time in Greece.

Abstract

Agaricus sect. Minores is characterized by the production of small to medium-sized basidiomata, high species diversity (including several cryptic taxa), and occurrence in a large variety of habitats. A new species to science, i.e. Agaricus draconis, is formally described by adopting an integrative approach based on morphological features, molecular criteria, and habitat characteristics. The multilocus phylogenetic analysis performed through the use of the internal transcribed spacer (ITS), the partial nuc 28S rDNA (28S), and the translation elongation factor 1-alpha (TEF1-α) gene clearly demonstrates that A. draconis is a sister species to A. brunneolus and A. dulcidulus. In addition, A. draconis exhibits distinct morphological features, including a predominantly white, smooth pileus with occasional tinges of gray, orange, violet, or yellowish colors lacking appressed scales and a single, solid rhizomorph at the stipe base. Furthermore, the presence of another 12 species of the A. sect. Minores was assessed in Greece, six of which constitute first national records, i.e. A. edmondoi, A. gemlii, A. heinemannianus, A. jacobi, A. kerriganii, and A. marisae. The most notable morphological features of these six species are presented, and their distribution in Mediterranean Europe is discussed.