Impact of DNA data on fungal and yeast taxonomy

Abstract

The species richness and diversity existing in microorganisms are unparalleled on our planet. In recent years, the use of molecular techniques for the detection and identification of microorganisms, especially through DNA sequencing, has revolutionised the way taxonomists look at the systematics of a species, especially when applying multilocus sequence data and concepts such as the genealogical concordance phylogenetic species recognition (GCPSR) concept1. Particularly problematic topics arising in the fungi are, for example, naming pleomorphic fungi (that is, fungi for which a teleomorph, meaning sexual form, and one or more anamorphs, meaning asexual forms, are formed), polyphyletic genera (that is, the same genus being presented in several distinct phylogenetic lineages or clades), morphospecies (a species which is differentiated from other species based on its distinctive morphological characters) that in fact represent distinct phylogenetic lineages and how to deal with species that are only known by their DNA sequence(s). Here we provide a brief overview of the effects and implications that the applications of molecular techniques such as DNA sequencing are having on the taxonomy of fungi (part 1) and yeasts (part 2), with specific reference to those which can be cultured. Although fungi and yeasts both belong to the kingdom Fungi, sometimes different approaches to the taxonomy of these two ‘groups’ were followed in the past and, therefore, they are treated individually below. For the purpose of this overview, genera of Oomycetes are excluded.