Aspergillus verrucosus sp. nov., a xerophilic species isolated from house dust and honey in Japan.

Abstract

Three strains of a xerophilic Aspergillus species were isolated from house dust and honey in Japan. A molecular phylogenetic analysis based on the combined dataset for four regions (internal transcribed spacer rDNA, calmodulin, β-tubulin, and RNA polymerase II second largest subunit) revealed that the strains formed an independent lineage, sister to Aspergillus halophilicus classified in section Restricti. Morphological comparisons show that the strains differ from A. halophilicus in three aspects: (i) the size of cleistothecia, as well as the surface structure and size of ascospores, (ii) the ability to grow on Harrold's agar and dichloran 18 % glycerol agar, and (iii) the lack of conidiophore formation on potato dextrose agar +20 % NaCl. These strains could be clearly distinguished from all known Aspergillus section Restricti species. Therefore, we consider it to be a novel species and propose the name Aspergillus verrucosus sp. nov. (NBRC 115547T).