Phylogeny, evolution and a re-classification of the Lichinomycetes

Abstract

The Lichinomycetes is an independent lichenized lineage within the Ascomycota comprising ca. 390 species and 50 genera. Very few studies have dealt with family and genus classification using molecular data and many groups are in need of thorough revision. Thus, we constructed a multilocus phylogeny (mtSSU, RPB2 and mcm7 gene regions) including 190 specimens of Lichinomycetes belonging to 126 species. Ancestral state reconstruction analyses were carried out to trace the evolution of selected characters. The current classification scheme of the Lichinomycetes based on morphological and anatomical characters is in great conflict with the phylogenetic relationships resulting from the present study. The results suggest substantial non-monophyly at the family and genus levels. A revised classification is proposed here and an overview of genera accepted in the Lichinomycetes is given. Ancestral Lichinomycetes are reconstructed as crustose with pycnoascocarps and octosporous asci. We used a combination of characters to delineate groups including the ascoma development and the type of asci. The revised classification includes 11 new genera, five resurrected genera, and 54 new combinations distributed in four families (three emended and one new). Three new species are also described.