Towards evidence-based conservation of subterranean ecosystems.

Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems have traditionally been overlooked in global conservation agendas and multilateral agreements, a quantitative assessment of solution-based approaches to safeguard subterranean biota and associated habitats is timely. This assessment allows researchers and practitioners to understand the progress made and research needs in subterranean ecology and management. We conducted a systematic review of peer-reviewed and grey literature focused on subterranean ecosystems globally (terrestrial, freshwater, and saltwater systems), to quantify the available evidence-base for the effectiveness of conservation interventions. We selected 708 publications from the years 1964 to 2021 that discussed, recommended, or implemented 1,954 conservation interventions in subterranean ecosystems. We noted a steep increase in the number of studies from the 2000s while, surprisingly, the proportion of studies quantifying the impact of conservation interventions has steadily and significantly decreased in recent years. The effectiveness of 31% of conservation interventions has been tested statistically. We further highlight that 64% of the reported research occurred in the Palearctic and Nearctic biogeographic regions. Assessments of the effectiveness of conservation interventions were heavily biased towards indirect measures (monitoring and risk assessment), a limited sample of organisms (mostly arthropods and bats), and more accessible systems (terrestrial caves). Our results indicate that most conservation science in the field of subterranean biology does not apply a rigorous quantitative approach, resulting in sparse evidence for the effectiveness of interventions. This raises the important question of how to make conservation efforts more feasible to implement, cost-effective, and long-lasting. Although there is no single remedy, we propose a suite of potential solutions to focus our efforts better towards increasing statistical testing and stress the importance of standardising study reporting to facilitate meta-analytical exercises. We also provide a database summarising the available literature, which will help to build quantitative knowledge about interventions likely to yield the greatest impacts depending upon the subterranean species and habitats of interest. We view this as a starting point to shift away from the widespread tendency of recommending conservation interventions based on anecdotal and expert-based information rather than scientific evidence, without quantitatively testing their effectiveness.

Fungi populate deep-sea coral gardens as well as marine sediments in the Irish Atlantic Ocean.

Fungi populate deep Oceans in extreme habitats characterized by high hydrostatic pressure, low temperature and absence of sunlight. Marine fungi are potential major contributors to biogeochemical events, critical for marine communities and food web equilibrium under climate change conditions and a valuable source of novel extremozymes and small molecules. Despite their ecophysiological and biotechnological relevance, fungal deep-sea biodiversity has not yet been thoroughly characterized. In this study, we describe the culturable mycobiota associated with the deepest margin of the European Western Continental Shelf: sediments sampled at the Porcupine Bank and deep-water corals and sponges sampled in the Whittard Canyon. Eighty-seven strains were isolated, belonging to 43 taxa and mainly Ascomycota. Ten species and four genera were detected for the first time in the marine environment and a possible new species of Arachnomyces was isolated from sediments. The genera Cladosporium and Penicillium were the most frequent and detected on both substrates, followed by Candida and Emericellopsis. Our results showed two different fungal communities: sediment-associated taxa which were predominantly saprotrophic and animal-associated taxa which were predominantly symbiotic. This survey supports selective fungal biodiversity in the deep North Atlantic, encouraging further mycological studies on cold water coral gardens, often overexploited marine habitats.

White-Nose Syndrome Confirmed in Italy: A Preliminary Assessment of Its Occurrence in Bat Species.

Although no mass mortality has been recorded so far, the precise demographic effect of white-nose syndrome (WNS) on European bats still remains to be ascertained. Following the first isolation of P. destructans in Italy, further surveys were performed to assess the distribution of the fungus in NW Italy and its effects on bats. Data were collected from March 2019 to April 2020 at sites used for hibernation (six sites) and/or for reproduction (four sites) in Piedmont and Aosta Valley. A total of 138 bats, belonging to 10 species, were examined to identify clinical features possibly related to the fungal presence. Culture from swabs and the molecular identification of isolates confirmed the presence of P. destructans in bats from five sites, including two maternal roosts. Dermal fungal infiltration, the criterion to assess the presence of WNS, was observed in biopsies of bats belonging to Myotis blythii, M. daubentonii, M. emarginatus and M. myotis. This is the first report of the disease in Italy. The results suggest a greater susceptibility to the infection of the genus Myotis and particularly of M. emarginatus, possibly due to the long length of its hibernation period. Other fungal dermatophytes were also observed.

Marine Fungi from the Sponge Grantia compressa: Biodiversity, Chemodiversity, and Biotechnological Potential.

The emergence of antibiotic resistance and viruses with high epidemic potential made unexplored marine environments an appealing target source for new metabolites. Marine fungi represent one of the most suitable sources for the discovery of new compounds. Thus, the aim of this work was (i) to isolate and identify fungi associated with the Atlantic sponge Grantia compressa; (ii) to study the fungal metabolites by applying the OSMAC approach (one strain; many compounds); (iii) to test fungal compounds for their antimicrobial activities. Twenty-one fungal strains (17 taxa) were isolated from G. compressa. The OSMAC approach revealed an astonishing metabolic diversity in the marine fungus Eurotium chevalieri MUT 2316, from which 10 compounds were extracted, isolated, and characterized. All metabolites were tested against viruses and bacteria (reference and multidrug-resistant strains). Dihydroauroglaucin completely inhibited the replication of influenza A virus; as for herpes simplex virus 1, total inhibition of replication was observed for both physcion and neoechinulin D. Six out of 10 compounds were active against Gram-positive bacteria with isodihydroauroglaucin being the most promising compound (minimal inhibitory concentration (MIC) 4-64 µg/mL) with bactericidal activity. Overall, G. compressa proved to be an outstanding source of fungal diversity. Marine fungi were capable of producing different metabolites; in particular, the compounds isolated from E. chevalieri showed promising bioactivity against well-known and emerging pathogens.

The culturable mycobiota of Flabellia petiolata: First survey of marine fungi associated to a Mediterranean green alga.

Algae-inhabiting marine fungi represent a taxonomically and ecologically interesting group of microorganisms still largely neglected, especially in temperate regions. The aim of this study was to isolate and to identify the culturable mycobiota associated with Flabellia petiolata, a green alga frequently retrieved in the Mediterranean basin. Twenty algal thalli were collected from two different sampling sites in the Mediterranean Sea (Elba Island, Italy). A polyphasic approach showed the presence of a relevant alga-associated mycobiota with 64 taxa identified. The fungal isolates belonged mainly to Ascomycota (61 taxa), while only three Basidiomycota were detected. The phylogenetic position of sterile mycelia and cryptic taxa, inferred on the basis of LSU partial region, highlighted the presence of putative new phylogenetic lineages within Dothideomycetes and Sordariomycetes. This work represents the first quali-quantitative analysis of the culturable mycobiota associated to a green alga in the Mediterranean Sea.