The Numbers Behind Mushroom Biodiversity

Fungi are among the most diverse groups of organisms on Earth. with a global diversity estimated at 0.8 million to 5.1 million species. They play fundamental ecological roles as decomposers, mutualists, and pathogens, growing in almost all habitats and being important as sources of food and health benefits, income, and to maintain forest health. Global assessment of wild edible fungi indicate the existence of 2327 useful wild species; 2166 edible and 1069 used as food; 470 medicinal species. Several million tonnes are collected, consumed, and sold each year in over 80 countries. The major mushroom-producing countries in 2012 were China, Italy, USA, and The Netherlands, with 80% of the world production, 64% of which came from China. The European Union produces 24% of the world production. Italy is the largest European producer, Poland is the largest exporter, UK the largest importer.Fungi are difficult to preserve and fossilize and due to the poor preservation of most fungal structures, it has been difficult to interpret the fossil record of fungi. Hyphae, the vegetative bodies of fungi, bear few distinctive morphological characteristicss, and organisms as diverse as cyanobacteria, eukaryotic algal groups, and oomycetes can easily be mistaken for them (Taylor & Taylor 1993). Fossils provide minimum ages for divergences and genetic lineages can be much older than even the oldest fossil representative found. According to Berbee and Taylor (2010), molecular clocks (conversion of molecular changes into geological time) calibrated by fossils are the only available tools to estimate timing of evolutionary events in fossil‐poor groups, such as fungi. The arbuscular mycorrhizal symbiotic fungi from the division Glomeromycota, generally accepted as the phylogenetic sister clade to the Ascomycota and Basidiomycota, have left the most ancient fossils in the Rhynie Chert of Aberdeenshire in the north of Scotland (400 million years old). The Glomeromycota and several other fungi have been found associated with the preserved tissues of early vascular plants (Taylor et al. 2004a). Fossil spores from these shallow marine sediments from the Ordovician that closely resemble Glomeromycota spores and finely branched hyphae arbuscules within plant cells were clearly preserved in cells of stems of a 400 Ma primitive land plant, Aglaophyton, from Rhynie chert 455–460 Ma in age (Redecker et al. 2000; Remy et al. 1994) and from roots from the Triassic (250–199 Ma) (Berbee & Taylor 2010; Stubblefield et al. 1987).info:eu-repo/semantics/publishedVersio