title: Cyphobasidium gen. nov., a new lichen-inhabiting lineage in the Cystobasidiomycetes (Pucciniomycotina, Basidiomycota, Fungi).
abstract: Pucciniomycotina is a highly diverse group of fungi, showing a remarkably wide range of lifestyles and ecologies. However, lichen-inhabiting fungi are only represented by a few species included in the genera Chionosphaera and Cystobasidium, and their phylogenetic position has never been investigated. Phylogenetic analyses using the nuclear SSU, ITS, and LSU ribosomal DNA markers reveal that the lichenicolous members of Cystobasidium (C. hypogymniicola, C. usneicola) form a monophyletic group distinct from Cystobasidium and outside the Cystobasidiales. The new genus Cyphobasidium is consequently described to accommodate these lichen-inhabiting species. Cyphobasidium is characterized by producing conspicuous galls on the host lichen thalli, by having distinctive basidia that arise from a thick-walled, cup-like structure, the probasidium, that persists after the senescence of the actual basidium (meiosporangium), and by its lichenicolous occurrence on species of Hypogymnia and Usnea. Cyphobasidium is one of the few representatives of the Cystobasidiomycetes in which the sexual stage predominates in nature, whereas most species in the group are known only from an asexual yeast phase. This is the first time the position of lichen-inhabiting taxa within the Pucciniomycotina is investigated using molecular data.
authors.affiliation: Universidad Rey Juan Carlos, Departmento de Biología y Geología, Física y Química Inorgánica, E-28933 Móstoles, Spain. Electronic address: ana.millanes@urjc.es.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Millanes
authors.affiliation: Musée national d'histoire naturelle, 25 rue Munster, L-2160 Luxembourg, Luxembourg.
authors.forename: Paul
authors.initials: P
authors.lastname: Diederich
authors.affiliation: Swedish Museum of Natural History, Department of Botany, P.O. Box 50007, SE-104 05 Stockholm, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Wedin
mesh_terms: D001487:Basidiomycota / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D004271:DNA, Fungal / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D008011:Lichens / Q000382:microbiology*; D010802:Phylogeny
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal
keywords: Cystobasidiales; Integrative taxonomy; Lichenicolous fungi; Mycoparasites