6 Pezizomycotina: Dothideomycetes and Arthoniomycetes

Abstract

The modern concepts of Dothideomycetes and Arthoniomycetes can be traced back to Luttrell (Mycologia 47:511–532, 1955) who, relying on data from a number of previous publications, combined lichenized and nonlichenized fungi in a single class, Loculoascomycetes. A current concept of two separate classes, as well-defined sister taxa, is still new, but it is closely tied to the use of DNA-sequence-based phylogenies to define fungal taxa. DNA sequence comparisons, which have now been in use in mycology since the early 1990s, confirmed that important morphological and developmental characters traditionally used in the taxonomy of loculoascomycetes are homoplasious. What was earlier referred to as the bitunicate ascomycetes contains multiple diverse lineages, which have now been placed in three different classes within Ascomycota. The class Eurotiomycetes contains Pyrenulales, Verrucariales, and Chaetothyriales within subclass Chaeothyriomycetidae (Geiser et al. Mycologia 98:1053–1064, 2006) and the remaining (and majority of) bitunicate species reside within two sister classes, Arthoniomycetes and Dothideomycetes. This review describes the latest taxonomic classifications substantiated with DNA and protein sequence comparisons and discusses morphology, biology, and ecology within this context.