Phylogeny of selected aquatic hyphomycetes based on morphological and molecular data

The phylogenetic relationships of 11 species (pleomorphic as well as holoanamorphic) of aquatic hyphomycetes were analysed. The study comprised seven type species of anamorphic genera. Analyses of sequences of different rDNA regions reinforced the assumption of a polyphyletic origin of aquatic hyphomycetes. On the basis of 18S rDNA data, nine species (Tetracladium marchalianum, Lemonniera terrestris, L. aquatica, Varicosporium elodeae, Tricladium angulatum, T. splendens, Alatospora acuminata, Anguillospora crassa, and A. furtiva) were placed in the Ascomycota class Leotiomycetes. Heliscus lugdunensis and Anguillospora longissima belong to the classes Sordariomycetes and Dothideomycetes, respectively. According to ITS and LSU sequences, T. marchalianum most likely belongs to the Helotiales. ITS sequence data separate two morphotypes of A. acuminata and two clades named the sensu lato and the sensu stricto, respectively. T. splendens showed close relationships with A. crassa and the marine hyphomycete Zalerion varium in ITS analyses, all affiliated to the Helotiales. T. angulatum is also related to the Helotiales but showed closer relation to members of the family Hyaloscyphaceae as revealed from ITS analyses. A. longissima is a member of the Pleosporales. According to a recent molecular phylogenetic concept of Lophiostoma and Massarina, A. longissima is close to Lophiostoma.