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Two new psychrophilic Pseudogymnoascus species with Geomyces anamorphs are described from a Sphagnum bog in Alberta, Canada. Pseudogymnoascus appendiculatus has long, branched, orange appendages and smooth, fusoid to ellipsoidal ascospores with a faint longitudinal rim. Pseudogymnoascus verrucosus has short, subhyaline appendages and warty peridial hyphae and ascospores, and both smooth to asperulate and irregularly warty conidia. Both species produce asci in chains, a feature that supports the distinction between this group and Myxotrichum, which produces asci singly. The discovery of species intermediate between Pseudogymnoascus and Gymnostellatospora, in having both ornamented ascospores and Geomyces anamorphs, prompted a re-evaluation of the genera. Sequence analysis of the internal transcribed spacer regions (ITS) of the nuclear ribosomal DNA indicates that the two genera remain distinct and comprise a monophyletic group. Pseudogymnoascus species have smooth to warty or lobate-reticulate ascospores while species of Gymnostellatospora have walnut-shaped spores with distinct longitudinal crests and striations. Anamorphs assignable to the form genus Geomyces are allied with both genera. A key is provided to the four species and varieties of Pseudogymnoascus.

Nuclear ribosomal DNA sequences (ITS region) of fifteen species in the hyphomycete genus Oidiodendron and ten species from the 4 genera in the Myxotrichaceae, Byssoascus, Gymnostellatospora, Myxotrichum, and Pseudogymnoascus, were analysed to: (i) reveal the levels of intra- versus interspecific sequence variation within the genus Oidiodendron, clarify species delimitation and examine the useful- ness of some morphological characters used for iden- tification; (ii) assess the possible conspecificity of doc- umented ericoid mycorrhizal strains of Oidiodendron; and (iii) test the hypothesis based on morphological inference that the genus Oidiodendron belongs with the genus Myxotrichum in the Myxotrichaceae (Ony- genales). Comparison of molecular and morpholog- ical data for multiple strains of 0. griseum, 0. tenuis- simum and 0. maius revealed that conidiophore length and the production of a diffusing pigment are not reliable key characters for the genus. Several his- torically important ericoid mycorrhizal strains, doc- umented as 0. griseum, were reidentified as 0. maius. Parsimony analyses of 23 Oidiodendron strains showed that three highly supported monophyletic groups, each one consisting of a pair of species, are resolved within the genus. A low level of sequence divergence between the species in these pairs suggests conspe- cificity for each pair. Other interspecific relationships were not well-supported by bootstrap values. Parsi- mony analysis of a second dataset composed of mi- totic and meiotic taxa showed that Oidiodendron, My- xotrichum and Byssoascus form a well-supported monophyletic group within the Myxotrichaceae, and

White-nose syndrome (WNS) is an emerging disease causing unprecedented morbidity and mortality among bats in eastern North America. The disease is characterized by cutaneous infection of hibernating bats by the psychrophilic fungus Geomyces destructans. Detection of G. destructans in environments occupied by bats will be critical for WNS surveillance, management and characterization of the fungal lifecycle. We initiated an rRNA gene region-based molecular survey to characterize the distribution of G. destructans in soil samples collected from bat hibernacula in the eastern United States with an existing PCR test. Although this test did not specifically detect G. destructans in soil samples based on a presence/absence metric, it did favor amplification of DNA from putative Geomyces species. Cloning and sequencing of PCR products amplified from 24 soil samples revealed 74 unique sequence variants representing 12 clades. Clones with exact sequence matches to G. destructans were identified in three of 19 soil samples from hibernacula in states where WNS is known to occur. Geomyces destructans was not identified in an additional five samples collected outside the region where WNS has been documented. This study highlights the diversity of putative Geomyces spp. in soil from bat hibernacula and indicates that further research is needed to better define the taxonomy of this genus and to develop enhanced diagnostic tests for rapid and specific detection of G. destructans in environmental samples.