This paper provides an updated classification of the Kingdom Fungi (including fossil fungi) and fungus-like taxa.Five-hundred and twenty-three (535) notes are provided for newly introduced taxa and for changes that have been made since the previous outline.In the discussion, the latest taxonomic changes in Basidiomycota are provided and the classification of Mycosphaerellales are broadly discussed.Genera listed in Mycosphaerellaceae have been confirmed by DNA sequence analyses, while doubtful genera (DNA sequences being unavailable but traditionally accommodated in Mycosphaerellaceae) are listed in the discussion.Problematic genera in Glomeromycota are also discussed based on phylogenetic results.

Outline of Fungi and fungus-like taxa – 2021