Environmental changes and heavy metal pollution are some of the consequences of anthropogenic activities. Many ecosystems, including edaphic ecosystems, suffer from the effects of pollution. The accurate assessment of soil heavy metal contamination leads to better approaches for remediating soils. The exploration of different ways, including biological methods, to conduct environmental monitoring is still ongoing. Here, we focus on reviewing the potential of ectomycorrhizal fungi as a natural indicator of soil heavy metal pollution. Mycorrhizal fungi fulfill basic criteria required as natural bio-indicators for heavy metal contamination. These fungi use different mechanisms such as avoidance and tolerance to survive in metalliferous soils. Thus, we promote ectomycorrhizal fungi as natural indicators. This review also synthesizes existing research on ectomycorrhizal mushrooms as natural bio-indicators for heavy metal pollution and the elaboration of mechanisms, by which ectomycorrhizal fungi meet the criteria required for a successful bio-indicator.

Materials and methods Sample collection and macromorphological character examinationThe Entoloma specimens were collected during field excursions in Mengsong, Yunnan Province, between May and September 2014. The basidiomata were photographed in the field using a digital camera. Information including habitat, ecotype, and attached substrate as well as Abstract: A new agaric species, Entoloma mengsongense, is described and illustrated from samples collected in Mengsong, Yunnan Province, China. Microscopic observations were carried out to describe the micro-and macromorphological characteristics of specimens, and molecular identification was performed to verify the novelty of the species. The species is mainly recognized by its conical to planoconcave pileus, with yellowish brown fibril and 4-8 × 4-6 µm sized, cuboid-quadrate basidiospores. Molecular phylogenetic analysis using ITS sequence data also indicated that this is a new species closely related to E. virescens and E. hochstetteri. Morphological and molecular phylogenetic differences separate E. mengsongense from all other known species of Entoloma.