Antarctic cryptoendolithic fungal communities are highly adapted and dominated by Lecanoromycetes and Dothideomycetes

This is the accepted manuscript of the paper:

Coleine C., Stajich J.E., Zucconi L., Onofri S., Pombubpa N., Egidi E., Franks A., Buzzini P., Selbmann L. (2018). Antarctic cryptoendolithic fungal communities are highly adapted and dominated by Lecanoromycetes and Dothideomycetes. Frontiers in Microbiology, Vol. 9, Art. 1392, doi.org/10.3389/fmicb.2018.01392

Abstract:

Endolithic growth is one of the most spectacular microbial adaptations to extreme
environmental constraints and the predominant life-form in the ice-free areas of
Continental Antarctica. Although Antarctic endolithic microbial communities are known
to host among the most resistant and extreme-adapted organisms, our knowledge on
microbial diversity and composition in this peculiar niche is still limited. In this study, we
investigated the diversity and structure of the fungal assemblage in the cryptoendolithic
communities inhabiting sandstone using a meta-barcoding approach targeting the
fungal Internal Transcribed Sequence region 1 (ITS1). Samples were collected from 14
sites in the Victoria Land, along an altitudinal gradient ranging from 1,000 to 3,300 m
a.s.l. and from 29 to 96 km distance to coast. Our study revealed a clear dominance of a
‘core’ group of fungal taxa consistently present across all the samples, mainly composed
of lichen-forming and Dothideomycetous fungi. Pareto-Lorenz curves indicated a very
high degree of specialization (F0 approximately 95%), suggesting these communities
are highly adapted but have limited ability to recover after perturbations. Overall, both
fungal community biodiversity and composition did not show any correlation with the
considered abiotic parameters, potentially due to strong fluctuations of environmental
conditions at local scales.