title: The molecular phylogeny of aquatic hyphomycetes with affinity to the Leotiomycetes.
abstract: Aquatic hyphomycetes play a key role in decomposition of submerged organic matter and stream ecosystem functioning. We examined the phylogenetic relationships among various genera of aquatic hyphomycetes belonging to the Leotiomycetes (Ascomycota) using sequences of internal transcribed spacer (ITS) and large subunit (LSU) regions of rDNA generated from 42 pure cultures including 19 ex-types. These new sequence data were analyzed together with additional sequences from 36 aquatic hyphomycetes and 60 related fungi obtained from GenBank. Aquatic hyphomycetes, characterized by their tetraradiate or sigmoid conidia, were scattered in nine supported clades within the Helotiales (Leotiomycetes). Tricladium, Lemonniera, Articulospora, Anguillospora, Varicosporium, Filosporella, and Flagellospora are not monophyletic, with species from the same genus distributed among several major clades. The Gyoerffyella clade and the Hymenoscyphus clade accommodated species from eight and six different genera, respectively. Thirteen aquatic hyphomycete taxa were grouped in the Leotia-Bulgaria clade while twelve species clustered within the Hymenoscyphus clade along with several amphibious ascomycetes. Species of Filosporella and some species from four other aquatic genera were placed in the Ascocoryne-Hydrocina clade. It is evident that many aquatic hyphomycetes have relatives of terrestrial origin. Adaptation to colonize the aquatic environment has evolved independently in multiple phylogenetic lineages within the Leotiomycetes.
authors.affiliation: Federal Environment Agency, Corrensplatz 1, 14195 Berlin, Germany; Department of Environmental Microbiology, Technische Universitaet Berlin, Ernst-Reuter-Platz 1, 10587 Berlin, Germany. Electronic address: christiane.baschien@tu-berlin.de.
authors.forename: Christiane
authors.initials: C
authors.lastname: Baschien
authors.forename: Clement Kin-Ming
authors.initials: CK
authors.lastname: Tsui
authors.forename: Vladislav
authors.initials: V
authors.lastname: Gulis
authors.forename: Ulrich
authors.initials: U
authors.lastname: Szewzyk
authors.forename: Ludmila
authors.initials: L
authors.lastname: Marvanová
mesh_terms: D001203:Ascomycota / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020459:Genes, rRNA; D008969:Molecular Sequence Data; D010802:Phylogeny; D012331:RNA, Fungal / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics; D017422:Sequence Analysis, DNA; D014871:Water Microbiology
chemical_list: D004271:DNA, Fungal; D004275:DNA, Ribosomal; D012331:RNA, Fungal; D012335:RNA, Ribosomal; C065096:RNA, ribosomal, 26S
keywords: Biodiversity; Evolution; Molecular systematics; Taxonomy