Abstract
This is a continuation of the papers "Towards a classification of Sordariomycetes" (2015) and "Families of Sordariomycetes" (2016) in which we compile a treatment of the class Sordariomycetes. The present treatment is needed as our knowledge has rapidly increased, from 32 orders, 105 families and 1331 genera in 2016, to 45 orders, 167 families and 1499 genera (with 308 genera incertae sedis) at the time of publication. In this treatment we provide notes on each order, families and short notes on each genus. We provide up-to-date DNA based phylogenies for 45 orders and 163 families. Three new genera and 16 new species are introduced with illustrations and descriptions, while 23 new records and three new species combinations are provided. We also list 308 taxa in Sordariomycetes genera incertae sedis. For each family we provide general descriptions and illustrate the type genus or another genus, the latter where the placement has generally been confirmed with molecular data. Both the sexual and asexual morphs representative of a family are illustrated where available. Notes on ecological and economic considerations are also given.