A multigene phylogeny of the Dothideomycetes using four nuclear loci

Abstract

We present an expanded multigene phylogeny of the Dothideomycetes. The final data matrix consisted of four loci (nuc SSU rDNA, nuc LSU rDNA, TEF1, RPB2) for 96 taxa, representing five of the seven orders in the current classification of Dothideomycetes and several outgroup taxa representative of the major clades in the Pezizomycotina. The resulting phylogeny differentiated two main dothideomycete lineages comprising the pseudoparaphysate Pleosporales and aparaphysate Dothideales. We propose the subclasses Pleosporomycetidae (order Pleosporales) and Dothideomycetidae (orders Dothideales, Capnodiales and Myriangiales). Furthermore we provide strong molecular support for the placement of Mycosphaerellaceae and Piedraiaceae within the Capnodiales and introduce Davidiellaceae as a new family to accommodate species of Davidiella with Cladosporium anamorphs. Some taxa could not be placed with certainty (e.g. Hysteriales), but there was strong support for new groupings. The clade containing members of the genera Botryosphaeria and Guignardia resolved well but without support for any relationship to any other described orders and we hereby propose the new order Botryosphaeriales. These data also are consistent with the removal of Chaetothyriales and Coryneliales from the Dothideomycetes and strongly support their placement in the Eurotiomycetes.

• bitunicate asci
• hamathecium
• loculoascomycetes
• pseudoparaphyses

We thank Walter Gams for assistance with the Latin diagnosis and are grateful to Gary Samuels, Clement Tsui and Gillian Turgeon for photographs provided. Computational assistance by Scott Givan and Chris Sullivan from the Center for Gene Research and Biotechnology at Oregon State University is appreciated. The efforts of Ben O’Rourke at Oregon State University and Lisa Bukovnik at Duke University were vital in generating sequence data. We thank Richard Oliver for providing data from the Phaeosphaeria nodorum genome project. The authors also acknowledge the important contributions of Ewald Groenewald, Mahdi Arzanlou and other personnel at CBS. Finally, we acknowledge financial support from the National Science Foundation (DEB-0228725, Assembling the Fungal Tree of Life and DEB-0090301, Research Coordination Network: A Phylogeny for Kingdom Fungi).