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False smut caused by Cercospora seminalis is an important disease of buffalograss (Buchloedacty- loides) affecting seed production. The pathogen prevents normal caryopsis development and causes considerable yield loss and reduced seed germina- tion. The current taxonomic placement of the false- smut causal pathogen in the genus Cercospora is incorrect based on its morphological characteristics and DNA phylogeny. In the present study the phylogenetic position of C. seminalis is clarified based on DNA sequence analysis of three loci namely the internal transcribed spacer (ITS) region, partial nuclear ribosomal large subunit (LSU) and partial sequences of the RNA polymerase II second largest subunit (RPB2). A collection of C. seminalis isolates was made from buffalograss sites near Lincoln, Nebraska. DNA sequence data indicated that Cercos- pora seminalis is phylogenetically close to but distinct from species of Bipolaris and Curvularia (Pleospor- aceae, Pleosporales). Cercospora seminalis morpholog- ically had unique characteristics, namely densely aggregated and repeatedly branched conidiophores arising from a brown stroma, monotretic conidioge- nous cells with inconspicuous loci, and scolecospor- ous conidia with distosepta, and thickened, darkened hila. Porocercospora is introduced as a new genus to accommodate the buffalograss false-smut pathogen.

Sporothrix inflata is a saprobic member of the Ophiostoma stenoceras-Sporothrix schenckii species complex, reported mainly from soil. Ophiostoma bragantinum, an ascomycete described from Brazil, has been proposed as its possible teleomorph. Previous studies revealed that Sporothrix inflata is phenotypically and genetically variable, suggesting the existence of cryptic species. During a continued survey on the biodiversity of microfungi from different countries, seven isolates morphologically similar to S. inflata were obtained from soil samples collected in Spain and USA. In this study their phenotypic features and phylogenetic relationships were assessed. DNA sequence data of two nuclear loci revealed that these isolates correspond to two unnamed clades in S. inflata s.l., one of which also included the type strain of Humicola dimorphospora, a species that traditionally has been considered a synonym of S. inflata. These two groups are proposed herein as Sporothrix brunneoviolacea sp. nov. and Sporothrix dimorphospora comb. nov. S. brunneoviolacea is characterized phenotypically by the production of a diffusible violet-brown pigment in culture and mostly globose, pigmented, lateral blastoconidia. On the other hand S. dimorphospora lacks diffusible pigments and shows mostly subglobose to obovoid pigmented lateral blastoconidia. In contrast to the type strain of S. inflata S. brunneoviolacea and S. dimorphospora assimilate raffinose. The phylogenetic analysis suggested that the proposed anamorph-teleomorph connection between S. inflata and O. bragantinum might not be correct.

In a study on soil microfungi from different countries two new hyphomycetes were found. The first one, Ramophialophora humicola, isolated from a soil sample collected in Ronda (Spain), is characterized by producing profusely branched conidiophores ending in sterile, sometimes swollen apices, and subhyaline, dacryoid conidia borne from both integrated and discrete phialides with conspicuous collaretes. ITS sequence data reveal its relationships with members of the Sordariales and its genetic differences with other fungi morphologically close, such as Cladorrhinum spp. The second species, Fibulochlamys chilensis, isolated from a soil sample collected in LaJunta (Chile), is characterized by micronematous, clamped, mostly branched conidiophores producing thallic, one-celled, thick-walled conidia that exhibit strongly wrinkled surfaces in age. The analysis of partial sequences of the ITS region and 28S rRNA gene reveal that this fungus is close to members of the gilled Agaricales.

Two interesting fungi belonging to the genus Cordana have been isolated recently in Spain from plant debris. Both are proposed here as new species, described and illustrated. Cordana mercadiana sp. nov. produces 0-1-septate conidia, with a prominent basal scar. Cordana verruculosa sp. nov. differs from the other species of the genus by its unique combination of aseptate, verruculose and small conidia. Both species are compared morphologically with other species of Cordana and their identities supported by the analysis of rDNA sequences. LSU sequence analysis revealed the congeneric relationship of Cordana and Pseudobotrytis; the members of both genera are in a well supported monophyletic lineage that appears to be related to the Coniochaetales but remains incertae sedis within the Sordariomycetes. To establish nomenclatural stability of the genus Cordana, an isolate of C. pauciseptata is designed here as epitype and the two species of Pseudobotrytis are transferred to Cordana. A dichotomous key is provided to identify the currently accepted species of Cordana.

Two new species of Cladorrhinum, C. flexuosum and C. microsclerotigenum, are described and their sequences of the 5.8S and 28S ribosomal DNA and internal transcribed spacers 1 and 2 of the ribosomal RNA gene cluster analyzed. Cladorrhinum flexuosum, isolated from soil in Spain, forms fast-growing, dull yellow colonies, flexuous conidiophores and globose to dacryoid conidia. Cladorrhinum microsclerotigenum, isolated from Musa sp. in Turkey, strongly resembles Cladorrhinum phialophoroides in the production of abundant terminal phialides, ellipsoid conidia and microsclerotia in culture. It differs from C. phialophoroides in its ability to grow at 36 C and high number of intercalary phialides, which only infrequently occur in C. phialophoroides.