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We describe two novel fungi isolated from soil samples collected in Northern Argentina and belonging to the family Aspergillaceae of the order Eurotiales: Leiothecium cristatum sp. nov. and Aspergillus posadasensis sp. nov. Leiothecium cristatum sp. nov., represented by the ex-type strain FMR 11998(T) ( = CBS 134260(T) = NBRC 109843(T)), is distinguishable morphologically from the type species of the genus, Leiothecium ellipsoideum, by the presence of irregular reticulate ascospores with two prominent equatorial crests, and Aspergillus posadasensis sp. nov., represented by the ex-type strain FMR 12168(T) ( = CBS 134259(T) = NBRC 109845(T)), is differentiated from Aspergillus acanthosporus, the nearest species phylogenetically, by its non-sclerotioid ascomata and a lack of an asexual stage on all culture media tested. The taxonomic proposals are supported by the analysis of the sequences of the internal transcribed spacer region, the D1-D2 domains of the 28S rRNA gene, the fragments of the RNA polymerase II largest subunit, and the putative chaperonin complex related to TCP-1, β-tubulin and calmodulin genes., (© 2014 IUMS.)

We report a comprehensive multi-year study of thermophilic fungi at the Sevilleta National Wildlife Refuge in central New Mexico. Recovery of thermophilic fungi from soils showed seasonal fluctuations, with greater abundance correlating with spring and summer precipitation peaks. In addition to grassland soils, we obtained and characterized isolates from grassland and riparian litter, herbivore dung and biological soil crusts. All strains belonged to either the Eurotiales or Sordariales (Chaetomiaceae). No particular substrate or microhabitat associations were detected. Molecular typing of strains revealed substantial phylogenetic diversity, eight ad hoc phylogroups across the two orders were identified and genetic diversity was present within each phylogroup. Growth tests over a range of temperatures showed substantial variation in maximum growth rates among strains and across phylogroups but consistency within phylogroups. Results demonstrated that 45-50 C represents the optimal temperature for growth of most isolates, with a dramatic decline at 60 C. Most strains grew at 60 C, albeit slowly, whereas none grew at 65 C, providing empirical confirmation that 60 C presents an evolutionary threshold for fungal growth. Our results support the hypothesis that fungal thermophily is an adaptation to transient seasonal and diurnal high temperatures, rather than simply an adaptation to specialized high-temperature environments. We note that the diversity observed among strains and the frequently confused taxonomy within these groups highlight the need for comprehensive biosystematic revision of thermophilic taxa in both orders.

Eupenicillium parvum was recorded for first time during isolation of phosphate-solubilizing microorganisms from the tea rhizosphere. The fungus developed a phosphate solubilization zone on modified Pikovskaya agar, supplemented with tricalcium phosphate. Quantitative estimation of phosphate solubilization in Pikovskaya broth showed high solubilization of tricalcium phosphate and aluminium phosphate. The fungus also solubilized North Carolina rock phosphate and Mussoorie rock phosphate, and exhibited high levels of tolerance against desiccation, acidity, salinity, aluminium, and iron. Solubilization of inorganic phosphates by the fungus was also observed under high stress levels of aluminium, iron, and desiccation, though the significant decline in phosphate solubilization was marked in the presence of aluminium than iron. The fungal isolate showed 100% identity with E. parvum strain NRRL 2095 ITS 1, 5.8S rRNA gene and ITS 2, complete sequence; and 28S rRNA gene, partial sequence.

Phenotypic and genotypic characters of strains of Neosartorya spinosa and related taxa were analysed. N. spinosa, Neosartorya botucatensis and Neosartorya paulistensis had identical partial beta-tubulin and calmodulin gene sequences and could not be differentiated on macro- and micro-morphological characteristics, including by scanning electron microscopy. Based on partial beta-tubulin and calmodulin gene sequences and ascospore morphology, two separate groups are distinguished and are proposed as novel species. Neosartorya laciniosa sp. nov. has microtuberculate ascospores with two bent crests and two distinct equatorial rings of small projections. Neosartorya coreana sp. nov. has rugose to weak reticulate ascospores with two often bent crests, but without the equatorial rings of small projections. The type strain of N. laciniosa is CBS 117721T (=NRRL 35589T=KACC 41657T) and the type strain of N. coreana is CBS 117059T (=NRRL 35590T=KACC 41659T).