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The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg genomic DNA from G. destructans. The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was qualified further by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.

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.

The effects of growth temperature on soluble carbohydrate and lipid content of Humicola marvinii, Geomyces pannorum and Mortierella elongata isolated from the Antarctic (Signy Island; 60° 43′S, 45°38′W) were investigated. Each of these fungi responded differently to suboptimal growth temperatures. At low temperatures Humicola marvinii accumulated cryoprotective carbohydrates (trehalose intracellularly and glycerol extracellularly), whereas Geomyces pannorum responded by altering its lipid composition with increases in unsaturated lipid content and overall unsaturation index. In the case of Mortierella elongata, features that may influence its ability to grow at low temperatures included the absence of detectable ergosterol, the presence of stearidonic acid and increased amounts of intracellular trehalose when grown at lower temperatures. The relative importance of lipid and carbohydrate metabolism in adaptation to temperature stress in these fungi is discussed.

Soil microfungal communities of two ad- jacent, but differently aged Alnus viridis coenoses were studied using the soil dilution plate method. A total of 84 taxa were isolated: 59 from the young com- munity, 51 from the old and 26 taxa shared. Morti- erella parvispora and Pythium sp. had the highest den- sity values in the young and the old alder community, respectively. Species compositions were compared be- tween plots of the two communities using a metric multidimensional scaling and a correspondence anal- ysis. Both analyses grouped plots from the young and the old community separately, suggesting a correla- tion between the changes in the fungal species com- position and the age of the alder communities. The correspondence analysis produced two species groups more related to one set of plots or the other, together with another group formed of Mortierella, Micromucor, Geomyces and Trichoderma species, whose distributions were more closely related to the general abiotic conditions than the age of the alder com- munities. It is proposed that the significant differ- ences in the composition of the two fungal commu- nities mirror the existence of a seral fungal succes- sion paralleling the aging of the alder communities.

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.

Increased temperature of incubation induces growth in vitro of the parasitic forms of some of the fungi which cause systemic mycoses in man. DeMonbreun observed this phenomenon when he described the growth of Histoplasma capsulatum Darling in vitro on various culture media and under differing conditions of incubation (5). DeMonbreun described also the development in vitro of the yeast form of Blastomyces dermatitids Gilchrist & Stokes when cultures were incubated at 37 C (6). Redaelli and Ciferri reported that the parasitic, multiple-budding form of Paracoccidioides brasiliensis (Splendore) Almeida can be maintained in vitro at 37 C (13). The effects of temperature and other factors upon the morphology of these and other fungal pathogens of man have been reviewed in many papers (3, 4, 10, 11, 12, 14, 15). The most notable features of Emmonsia crescens Emmons & Jellison as it grows in the lungs of animals are its great increase in size (up to 106 increase in volume of the inhaled conidia), the great thickness of the wall (up to 70 /A) and its failure to reproduce in mammalian tissue in any manner. The parasitic form of this fungus can be produced in vitro by incubation of the fungus at 37 C (8). Because of these striking characteristics of E. crescens Emmons and Jellison proposed the name "adiaspore" for the transformed conidium which grows to an enormous size (up to 700 , in diam) in the lung of a naturally or experimentally infected animal without reproducing (8). Because of these unusual features, the generic name proposed by Ciferri and Montemartini (2) is retained in this paper. Carmichael has referred Emmonsia parva (Emmons & Ashburn) Ciferri & Montemartini, E. crescens (which he designated as a variety of E. parva), Blastomyces dermatitidis, Aleurisma spp. and Geomyces spp. to the genus Chrysosporium Corda without attaching sufficient importance to the in vivo behavior of these fungi (1). Chrysosporium spp., as defined by

Two new species of xerophilic fungi are described: Geomyces pulvereus Hocking & Pitt, and Monascus eremophilus Hocking & Pitt. The Monascus species is an obligate xerophile, which does not appear to have an anamorphic state. A further occurrence of Eurotium halophilicum is reported, and a full description of this rarely encountered species is given. During the course of investigations into spoilage of various low water activity (aw) foodstuffs and commodities over several years, three unusual xerophilic fungi were isolated. One was identified as Eurotium halophilicum Christensen et al., a rarely encountered xerophile, and it was concluded that the other isolates belonged to two previously undescribed species. Although one species is represented by only a single isolate, and the other by only two isolates, the new taxa are sufficiently distinctive to warrant description as new species. E. halophilicum has not been reported in the literature since it was described in 1959.