Diversity and distribution of fungal communities in lakes of Antarctica

Abstract

This study assessed the diversity and distribution of filamentous fungi obtained from water sampled from six lakes in the Antarctic Peninsula. One hundred and twenty-eight fungal isolates were purified and identified by analysis of nuclear rDNA ITS region sequences as belonging to 31 fungal different operational taxonomic units (OTUs). The most frequently isolated fungi were Geomyces pannorum and Mortierella sp.; these species occurred in six and three of the lakes sampled, respectively, and displayed the highest total colony-forming unit per L. Different species that have not been found to these lakes and/or had adapted to cold conditions were found. In general, the fungal community displayed low richness and high dominance indices. The species Cadophora cf. luteo-olivacea, Cadophora malorum, Davidiella tassiana, G. pannorum, Mortierella cf. alpina and Thelebolus cf. microsporus that were found in the lakes in question were also previously found in other cold ecosystems, such as Arctic, temperate and Alpine regions. The results of this study suggest the presence of an interesting aquatic fungal web, including symbionts, weak and strong saprophytes and parasite/pathogen fungal species. This aquatic web fungal may be a useful community model for further ecological and evolutionary studies of extreme habitats.