title: Annulusmagnus and Ascitendus, two new genera in the Annulatascaceae.
abstract: Two pyrenomycetes in the Annulatascaceae described from freshwater, Annulatascus triseptatus and Ascolacicola austriaca, are reported from North and South America for the first time. Both species occur commonly on submerged wood in the U.S.A. The two taxa are similar morphologically in having black coriaceous ascomata, cylindrical necks, septate paraphyses, cylindrical pedicellate asci with prominent apical rings and three-septate ascospores. Molecular data demonstrates that Annulatascus is polyphyletic, with A. triseptatus on a clade widely separated from the type species of the genus, A. velatisporus. Ascolacicola austriaca is on a monophyletic clade within the Annulatascaceae as sister taxon of A. triseptatus. Based on morphological data and phylogenetic analyses of 28S rDNA sequence data, new genera Annulusmagnus and Ascitendus are established for Annulatascus triseptatus and Ascolacicola austriaca, respectively.
authors.affiliation: Department of Plant Biology, University of Illinois, 265 Morrill Hall, 505 S. Goodwin Avenue, Urbana, Illinois 61801.
authors.forename: Jinx
authors.initials: J
authors.lastname: Campbell
authors.forename: Carol A
authors.initials: CA
authors.lastname: Shearer