Fungal strains isolated from rocks and lichens collected in the Antarctic ice-free area of the Victoria Land, one of the coldest and driest habitats on earth, were found in two phylogenetically isolated positions within the subclass Dothideomycetidae. They are here reported as new genera and species, Recurvomyces mirabilis gen. nov., sp. nov. and Elasticomyces elasticus gen. nov., sp. nov. The nearest neighbours within the clades were other rock-inhabiting fungi from dry environments, either cold or hot. Plant-associated Mycosphaerella-like species, known as invaders of leathery leaves in semi-arid climates, are also phylogenetically related with the new taxa. The clusters are also related to the halophilic species Hortaea werneckii, as well as to acidophilic fungi. One of the latter, able to grow at pH 0, is Scytalidium acidophilum, which is ascribed here to the newly validated genus Acidomyces. The ecological implications of this finding are discussed.

A wide sampling for isolating highly destructive and extremotolerant black fungi was performed from Italian monuments in selected historical sites which include the “Cortile della Pigna”, Vatican Museum and the St Peter colonnade (Vatican City State), the monumental cemetery of Bonaria (Cagliari), and other monuments in the city of Cagliari. Thirty out of seventy-four strains isolated were identified basing on ITS Blastn comparison. Based on multilocus phylogeny and morphological data, one new genus and species Lithophila guttulata, five new species Knufia marmoricola, K. vaticanii, K. karalitana, K. mediterranea and Exophiala bonariae, order Chaetothyriales and one new genus and species, Saxophila tyrrhenica, and two new species Vermiconia calcicola and Devriesia sardiniae, order Capnodiales, were proposed. Ecological considerations are put forward.

The last decade has revealed an unexpected fungal diversity associated with natural rocks, often collected in environments influenced by harsh climatic conditions. Yet the phylogenetic affiliations and the taxonomy of many of these extreme fungi, mainly within Dothideomycetes, the largest class of Ascomycota, have only partially been described. In the present study we confirm that most rock inhabiting-fungi (RIF) are highly polyphyletic among Dothideomycetidae, mainly within the order Capnodiales, an order otherwise incorporating several families of major plant pathological importance. Novel taxa were identified within the two major and distinct clades of Teratosphaeriaceae, both comprising meristematic black fungi. Thirty one novel species and 13 new genera are proposed, based on ITS and partial nucLSU, RPB2 and BT2 sequences.

Fungi play irreplaceable roles for ecosystem functioning. They may adopt different lifestyles, for example saprotrophs, symbionts or parasites: some species are cosmopolitan with a wide distribution and others, thanks to their ecological plasticity, may adapt to harsh environments precluded to most of life forms. In stressing conditions, their role is even more crucial for the recycling of organic matter or favoring nutrients uptake. When the conditions become really extreme and competition is low, fungi focus on extremotolerance and evolve peculiar competences to exploit natural or xenobiotic resources in the particular constrains imposed by the environment. This paper focuses on three different cases of fungal life in the extremes: hydrocarbon-polluted sites, extremely acidic substrates, and littoral dunes, aiming to give few but significant examples of the role of these fascinating organisms in peculiar habitats and the valuable biotechnological potentialities of the abilities they have evolved in response to such constrains.

Drylands account for 45% of the Earth’s land area, supporting ~40% of the global population. These regions support some of the most extreme environments on Earth, characterized by extreme temperatures, low and variable rainfall, and low soil fertility. In these biomes, microorganisms provide vital ecosystem services and have evolved distinctive adaptation strategies to endure and flourish in the extreme. However, dryland microbiomes and the ecosystem services they provide are under threat due to intensifying desertification and climate change. In this review, we provide a synthesis of our current understanding of microbial life in drylands, emphasizing the remarkable diversity and adaptations of these communities. We then discuss anthropogenic threats, including the influence of climate change on dryland microbiomes and outline current knowledge gaps. Finally, we propose research priorities to address those gaps and safeguard the sustainability of these fragile biomes.