Hymenomycetes

Hymenomycetes was the largest class of fungi within the division Basidiomycota, but the term is no longer taxonomically relevant. Many familiar fungi belong to this class, including bracket fungi and toadstools. This class contains the orders Agaricales, Boletales, and Russulales.

Formerly a taxonomic group of basidiomycetes, now understood as polyphyletic assemblage of basidiomycetes, the term refers to fungi with fruit bodies whose hymenophore develops either not enclosed or only so with a veil (velum), which is called a gymnocarpic or hemiangiocarpic ontogeny, respectively. Puffballs, on the other hand, have gasterocarpic development (hymenophore enclosed).

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