Phylogeny and morphology of dematiaceous freshwater microfungi from Perú.

A survey of freshwater ascomycetes conducted along an elevational gradient in Perú in the Districts of Cusco, Junín, and Madre de Dios yielded specimens of Cancellidium applanatum, Cordana abramovii, Sporoschisma juvenile, S. uniseptatum, and S. saccardoi. With the exception of S. saccardoi, these are new records for Perú. Molecular data was generated for three previously unsequenced species: Cancellidium applanatum, Cordana abramovii and Sporoschisma saccardoi. These taxa are reported herein from the neotropics with an accompanying phylogeny based on partial 28S nuclear ribosomal large-subunit sequence data. The sexual morph of S. saccardoi has previously been linked to Melanochaeta hemipsila through cultural studies. Molecular data from ascospores and conidia of M. hemipsila and S. saccardoi, respectively, were used to demonstrate a genetic connection of the sexual and asexual morphs of these fungi for the first time, resulting in the new combination Sporoschisma hemipsila being made.

A molecular phylogenetic assessment of the genus Gyromitra in North America.

Gyromitra is a widespread genus of macroscopic apothecial ascomycetes whose taxa may be mycorrhizal, saprophytic or parasitic. Nuclear ribosomal 28S large subunit sequence data from 35 specimens from North America, along with sequences available in GenBank, were used in maximum-parsimony, maximum-likelihood and Bayesian analyses to reconstruct a phylogeny of Gyromitra in North America. Gyromitra sensu lato forms a monophyletic group within the Discinaceae composed of five distinct subgenera and 11 well supported clades that include Discina, Hydnotrya and Pseudorhizina. A new subgenus is proposed to accommodate G. californica and G. sphaerospora.

Freshwater ascomycetes: Minutisphaera (Dothideomycetes) revisited, including one new species from Japan.

During investigations of freshwater ascomycetes we found one interesting taxon from Aomori (Japan), as well as three additional taxa from North Carolina (USA), which were morphologically similar to Minutisphaera, a recently described freshwater fungus in the Dothideomycetes. The ascomata of all the collections bore dark hair-like structures around the ostiolar region, obovoid to obclavate bitunicate asci, and one to three septate hyaline to brown ascospores with a sheath (in material from Japan), and with both sheath and appendages (in material from the USA). The apothecial ascomata of these taxa, however, differ from those of the type species of the genus, which are perithecial. Two collections of Minutisphaera-like fungi from the USA were morphologically quite similar but differed in ascospore size. To assess the phylogenetic affinities of Minutisphaera-like taxa with the type species, M. fimbriatispora, we sequenced 18S and 28S nrDNA of five newly collected strains of Minutisphaera. We also sequenced the nrDNA for the entire internal transcribed spacer region of 10 strains to assess interspecific and intraspecific variation with M. fimbriatispora. Additionally we examined the secondary metabolite profiles of two strains from USA. Based on maximum likelihood and Bayesian analyses of combined 18S and 28S, and separate ITS sequences, as well as examination of morphology, we describe and illustrate a new species, M. japonica. One collection from North Carolina is confirmed as M. fimbriatispora, while two other collections are Minutisphaera-like fungi that had a number of similar diagnostic morphological characters but differed only slightly in ascospore sizes. The phylogeny inferred from the internal transcribed spacer region suggested that two out of the three North Carolina collections may be novel and perhaps cryptic species within Minutisphaera. Organic extracts of Minutisphaera from USA, M. fimbriatispora (G155-1) and Minutisphaera-like taxon (G156-1), revealed the presence of palmitic acid and (E)-hexadec-9-en-1-ol as major chemical constituents. We discuss the placement of the Minutisphaera clade within the Dothideomycetes. The description of the genus Minutisphaera is emended to accommodate M. japonica within Minutisphaera.