Arthrocatenales, a new order of extremophilic fungi in the Dothideomycetes.

The widely treated order Capnodiales is one of the most important orders in the class Dothideomycetes. Recently, the order Capnodiales s. lat. was reassessed and split into seven orders (Capnodiales s. str., Cladosporiales, Comminutisporales, Mycosphaerellales, Neophaeothecales, Phaeothecales and Racodiales) based on multi-locus phylogeny, morphology and life strategies. In this study, two strains isolated from sooty mould communities on the leaves of and needles of in southern Poland were analyzed. Multi-locus phylogenetic analyses (ITS-LSU-SSU--) along with morphological examination showed that they belong to , which represents a sister taxon to . is a rock-inhabiting fungus described from Turkey. The following new combination is proposed: . Phylogenetic analyses also showed that and related genus , both known previously only from rocks, form a sister lineage to orders Cladosporiales and Comminutisporales. The new order Arthrocatenales and new family Arthrocatenaceae are proposed to this clade. Representatives of this order are extremophilic fungi that live on rocks and in sooty mould communities.