Results of a biodiversity study of Antarctic microfungi from ornithogenic soils are presented in this paper. A wide range of soil habitats within and adjacent to active and abandoned penguin rookeries were sampled in order to examine relationships between environmental factors and the biodiversity of soil microfungi. Soil samples were collected from two contrasting Antarctic locations: (1) Beaufort Island (Ross Sea, Continental Antarctica), which is largely ice- and snow-covered, isolated, difficult to access and infrequently visited, and (2) Barrientos Island (maritime Antarctica) which is mostly ice-free during summer and is often visited by scientists and tourists. Soil sampling at Beaufort and Barrientos Islands was completed during the austral summer seasons of 2004/05 and 2006/07, respectively. Warcup’s soil method was used for fungi cultivation. A total of 27 fungal taxa were isolated from the two study sites, consisting of 11 ascomycetes, 13 hyphomycetes
and three yeasts. Only three taxa — Geomyces sp., a pink and a white yeast — occurred on both sites. The isolated fungi were classified according to their thermal characteristics in culture, with seven psychrophilic, 10 psychrotrophic and 10 mesophilic fungi being isolated. Thelebolus microspores, Thelebolus sp., Geomyces sp. and Antarctomyces sp., were the most frequently isolated fungi. A total of 10 taxa were isolated from the 20 soil samples from Beaufort Island, consisting of five psychrophilic, four psychrotrophic and one mesophilic fungi. Thelebolus microsporus, Thelebolus sp., Asco BI8 and Phoma sp. were the most frequently obtained fungi
(20%–27% of isolates). A total of 22 fungal taxa were isolated from 23 soil samples from Barrientos Island, consisting of four psychrophilic, six psychrotrophic and 12 mesophilic fungi. Geomyces sp. and Antarctomyces sp. were the most frequently isolated taxa. Thus, the fungal diversity of Beaufort Island was dominated by Ascomycetes while that of Barrientos Island was dominated by hyphomycetes.