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In this study, we describe plant communities along the mesotopographic gradient in the low‐elevation subcontinental mountains of NE Finland (Utsjoki region). We sampled vascular plants, bryophytes and lichens along 18 mesotopographic ridge‐snowbed transects comprising a total of 180 plots. We used non‐metric multidimensional scaling (NMDS) ordination with envfit to explore the differentiation of plant communities in relation to mesotopography, elevation, rock cover, cover of bare ground, snowbed size and snowmelt time. The classification of communities was performed using DIANA clustering. Plant communities were differentiated along the mesotopographic gradient, snowmelt time, elevation and rock cover. The DIANA analysis distinguished seven clusters corresponding to the following communities: Betula nana–Lichenes heath, Empetrum–Myrtillus–Stereocaulon heath, Empetrum–Pleurozium–Lichenes heath, graminoid‐rich snow‐protected heath, Oreojuncus trifidus–Avenella flexuosa snow‐protected heath, Polytrichastrum sexangulare–liverwort snowbed, and Salix herbacea–Kiaeria starkei snowbed. Because of the strong impact of snowmelt time on plant community structure and distribution of communities, it is likely that climate change‐induced changes in snow conditions are affecting tundra vegetation and especially snowbeds are threatened. Snowbed communities in the Utsjoki region roughly align with previously described vegetation associations of mountain areas in NW Europe. The assignment of the graminoid‐rich snow‐protected heath community remains uncertain. [ABSTRACT FROM AUTHOR]

ABSTRACT The lichen genus Bagliettoa A. Massal. is being reported for the first time from India, represented by B. baldensis (A. Massal.) Vězda, B. calciseda (DC.) Gueidan & Cl. Roux, and B. limborioides A. Massal. Previously, specimens belonging to this genus were erroneously identified as species of Awasthiella and Verrucaria at herbarium LWG. Detailed descriptions, illustrations, notes on distribution and ecology, and a comparison with related species are provided along with a key to facilitate their identification. [ABSTRACT FROM AUTHOR]

Cliff ecosystems provide refuge to 35%–66% of the world's endemic plants. However, they face growing threats from sport climbing. Evidence suggests that unclimbed cliffs harbour approximately twice the plant richness compared with climbed cliffs, with increasing impact as climbing intensity increases. Unfortunately, it remains unknown whether the climbing impact on cliff vegetation originates from the development (opening) of climbing routes or from temporal changes resulting from subsequent climbing.We recorded cliff vascular plants and lichens at the protected natural area of El Potrero Chico (Mexico) before and after the development of new climbing routes. Subsequently, we re‐recorded the routes at sequential timepoints after 10, 20, and 30 ascents. Additionally, we examined whether the abundance of cliff vegetation influences the extent of climbing impact and whether the surroundings of the routes were also affected.We found that the opening of climbing routes exerted the strongest negative effects on cliff plants, reducing species richness by 38%, while subsequent ascents generated a minimal impact. Worryingly, route opening affected not only species richness in the route itself but also the surroundings of the routes. After 30 ascents, cliff plant abundance decreased by 60.6% within the bolted routes, whereas it decreased by 42.3% in the surroundings. However, this impact depended on the original cliff vegetation abundance. Lichen cover showed a gradual decrease, indicating that cliff‐dwelling lichens are affected not only by the opening of the route but also by subsequent ascents.Synthesis and applications: Given the almost non‐existent regulation of outdoor climbing activities in most countries, we urge the implementation of a conservation management protocol that defines clear strategies to regulate climbing activities and preserve pristine cliffs. On yet unclimbed cliffs with narrow endemic, rare, or threatened species, we propose banning the establishment of new climbing areas. On climbed cliffs lacking protected species, dynamic management actions should be implemented, such as setting a maximum number of routes that can be established and defining limits of acceptable change as climbing intensity increases. The proposed conservation management should help to halt the loss of unique cliff biodiversity and safeguard pristine cliff ecosystems. [ABSTRACT FROM AUTHOR]

Despite their ecological significance, non‐vascular photoautotrophs (NVPs) are frequently excluded from ecological experimental studies, leading to a limited comprehension of how their communities are affected by the ecosystem dynamics and an underestimation of their role in ecosystem functioning. We studied the impact of vascular plant taxonomic and functional diversity on three groups of ground NVPs (lichens, bryophytes, and cyanobacteria) within one of the longest‐running plant biodiversity experiments (Biodiversity and Ecosystem Function at Cedar Creek Ecosystem Science Reserve). Utilizing the permanent plot framework of this experiment, we analyzed the effects of almost 30 years of treatment across various levels of vascular plant taxonomic and functional diversity on NVPs. For each diversity level we documented NVP cover and richness. Using generalized linear models we evaluated the effect of vascular plant taxonomic and functional diversity, as well as environmental factors affected by vascular diversity (such as vascular plant cover, light penetration, soil nutrient content, and microtopography) on NVP richness and cover. Using these models, we conducted structural equation modeling analyses (SEM) that allowed us to differentiate the direct and indirect impacts of vascular plant taxonomic and functional diversity on NVPs. Our results showed that both lichen and bryophyte richness and cover decreased with higher vascular plant taxonomic and functional diversity, while cyanobacteria cover increased as a function of the same parameters. We also showed that microtopography serves as better predictor for lichens and bryophytes, while nutrient‐related factors perform better as predictors for cyanobacteria. Additionally, our findings indicate that NVP cover ranged from 0.001% to 100% (mean 15%) in the surveyed plots, representing a major, still ignored, component of the experimental plots. This study shows that vascular plant diversity directly and indirectly affects NVP communities, but the consequences of these effects at community and ecosystem levels are still to be explored. [ABSTRACT FROM AUTHOR]

Being poikilohydric, lichens are inherently exposed to alternating desiccation and hydration cycles. They can exhibit extraordinary resistance to extreme temperatures in a dehydrated state but thermal thresholds for hydrated lichens are lower. The ability of the lichen Cetraria aculeata to recovery after high temperature treatment (40°C, 60°C) at different air humidity levels (relative humidity [RH]: <15%, 25%, 50%, 75%, ≅100%) was examined to find a linkage between passive dehydration of the lichen and its physiological resistance to heat stress. The response to heating was determined by measuring parameters related to photosynthesis and respiration after 2‐ and 24‐h recovery. A higher RH level resulted in a slower decline in relative water content (RWC) in hydrated thalli. In turn, the stress resistance of active thalli depended on the ambient humidity and associated RWC reduction. Elevated temperature had a negative impact on bioenergetic processes, but only an unnatural state of permanent full hydration during heat stress resulted in a lethal effect. Hydrated lichen thalli heated at 40°C and 50% relative humidity (RH) tended to be least susceptible to stress‐induced damage. Although atypical climatic conditions may lead lichens to lethal thresholds, the actual likelihood of deadly threat to lichens due to heat events per se is debatable. Summary statement: Passive dehydration of lichens is a property that protects them well against the lethal effects of extreme temperatures. Heat stress takes its toll on viability of Cetraria aculeata but only in the unnatural state of its full hydration leads to fatal inhibition of photosynthesis and respiration. [ABSTRACT FROM AUTHOR]

The fruticose lichen Stereocaulon vesuvianum is among the most abundant and widespread lichens in upland Britain. It typically produces cephalodia (nodules) that contain the cyanobacterium Stigonema, which can fix atmospheric nitrogen. However, over much of England, Wales, and southern Scotland S. vesuvianum no longer produces cephalodia and does not fix nitrogen, a morphological change linked to elevated atmospheric nitrogen deposition. This provided a unique opportunity to compare the 15N natural abundance signatures in N2‐fixing and non‐N2‐fixing lichen populations, keeping in mind that fixed nitrogen has a 15N content close to that of atmospheric N2 while, in comparison, several components of atmospheric combined N (e.g. nitrate and ammonium in precipitation) tend to be 15N depleted. We found that in N2‐fixing samples, there was a steep gradient in 15N relative abundance in the terminal 15 mm of thallus branches (pseudopodetia), changing from 15N depleted tissues at 10–15 mm below the tips to values close to that of atmospheric N2 at the apices while in non‐N2‐fixing samples thallus branches were uniformly 15N depleted. The 15N gradient in N2‐fixing material could not be explained by the presence of cephalodia since these are more abundant towards branch bases. The data provide the first evidence in lichens of translocation of recently fixed N to sink regions of active growth and production of asexual reproductive propagules, bringing lichens into line with N source‐sink relationships in N2‐fixing plant symbioses. [ABSTRACT FROM AUTHOR]

Soil salinization is a major environmental threat to the entire terrestrial ecosystem. Lichens arose from the symbiosis of fungi and algae or cyanobacteria. They have a high tolerance to various extreme environments, including adaptation to saline‐alkali habitats. Thus, lichens are pioneer species on saline‐alkali soil. However, the separate resilience of the two symbiotic partners under saline‐alkali conditions remains insufficiently understood. In this study, two representative symbiotic algae, Diplosphaera chodatii and Trebouxia jamesii, were studied for their physiological response to the saline‐alkali stress by adjusting different concentrations of NaHCO3, together with their respective symbiotic fungi Endocarpon pusillum (terricolous lichen) and Umbilicaria muhlenbergii (saxicolous lichen). The results indicate that cell growth rate and biomass in all four cultures decreased in alkali‐alkaline substrate, while cellular activities and ultrastructure were affected to a distinct extent. Compared with the symbiotic fungi, the algae were found to be more active in coordinating oxidative stress and lipid peroxidation damage under the saline‐alkali stress. The antioxidant system of the alga was especially shown as a key adaptive trait and it provides an important strategy for species survival and persistence in arid saline‐alkali desert. The specific survival ability of the lichen symbiosis relies on the stress resilience advantages of the symbiotic partners in combination. Our study provided new insights into understanding the adaptation of lichen symbiosis to desert saline‐alkali soil, and the potential of lichen symbiotic algae in the future desert ecological restoration. [ABSTRACT FROM AUTHOR]

Biological soil crusts (biocrusts) can thrive under environmental conditions that are stressful for vascular plants such as high temperatures and/or extremely low moisture availability. In these settings, and in the absence of disturbance, cover of biocrusts commonly exceeds cover of vascular plants. Arid landscapes are also typically slow to recover from disturbance and prone to altered vegetation and invasion by exotic species. In the sagebrush ecosystems, cover of annual, exotic, invasive grasses are lower where cover of biocrusts and vascular plants are greater, suggesting that biocrusts play a role in helping arid sites avoid conversion to dominance by invasive grasses. The conceptual framework for assessing ecological resistance and resilience (R&R) is used across the region to estimate the risk of invasion by annual grasses and the likelihood of recovery of native plants following disturbance. However, this framework does not currently account for biocrusts. We used data collected by the Bureau of Land Management Assessment, Inventory, and Monitoring program to relate biocrusts, specifically the presence of lichens and mosses, to the R&R framework. Lichens frequently occur on warm, dry sites, classified as lower R&R. Mosses frequently occur on sites classified as moderate or moderately low R&R. Without management practices that favor biocrusts in low‐moderate R&R, these areas may be more vulnerable to transitioning from being dominated by shrubs to annual grasses. Under climate change scenarios, the area occupied by lower R&R sites is likely to increase, suggesting that the role of biocrusts in maintaining site resistance to invasion may also increase. [ABSTRACT FROM AUTHOR]

Restoring biological crust (biocrust) in disturbed drylands is challenging due to the difficult environmental conditions, such as limited soil moisture, low soil nutrients, and extreme temperatures, that impede growth. Understanding how the key components of biocrust—mosses, lichens, and cyanobacteria—react to different environmental factors informs the optimal timing, locations, and species composition for biocrust reintroduction, thereby increasing the likelihood of establishment. Here, we inoculated soils with a diverse range of biocrust organisms, analogous to seeding an area with diverse vascular plant seeds, and varied environmental conditions to observe how these changes influenced the development and functions of reintroduced biocrust. We found that by manipulating soil texture and time spent wet, we can change the proportional cover of biocrust within a restoration‐like setting. Specifically, we found that 4 months after inoculation, finer textured soils that received more water become dominated by moss cover, while coarser textured soils with less water remained dominated by cyanobacteria cover, and the interactions between texture and time spent wet strongly influenced cover. We found biocrust morphological group cover had a small, but detectable, effect on ecosystem functions (soil stability and nitrogenase activity, a proxy for nitrogen fixation), but that environmental conditions had a stronger impact on the functions we measured. Manipulative experiments in controlled environments, like this one, can help elucidate the mechanisms underlying the establishment rate and patterns of biocrusts post‐inoculation, and inform implementation of inoculations in the field. [ABSTRACT FROM AUTHOR]

This research presents the contents of K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Rb, Sr, and Pb in lichen and moss samples used as biomonitors of air pollution collected in Ulaanbaatar city. X‐ray fluorescence (XRF) methods were used, employing for excitation a Pd X‐ray tube with a molybdenum secondary target. Matrix effects were corrected by the use of normalization for the coherent and incoherent scattered peak, in this way the determination is more efficient. For quality control of the results, comparisons were made with results from other certified laboratories. No significant differences were found between the different techniques. The elemental distribution patterns obtained for each metal were associated with different pollution sources, thus contributing to the assessment of air pollution in Ulaanbaatar. [ABSTRACT FROM AUTHOR]

Questions: The alpine vegetation of the Alps is particularly vulnerable to climate change, as the temperature increase in this region is twice the global average and the available area for new colonisations decreases with increasing elevation. While numerous studies have investigated the response of vascular plants to a warming climate in the alpine belt, only a handful have investigated that of cryptogams in the European Alps. Based on a 21‐year monitoring project, we assessed the effects of climate change on cryptogams along elevation, from the treeline to the subnival belt. Location: Four GLORIA summits in Valais (Switzerland). Methods: Between 2001 and 2022, terricolous lichens and bryophytes (from 2008) were inventoried in 52 1‐m2 plots distributed across four summits: 2360 m a.s.l. (treeline), 2550 m (lower alpine), 2990 m (upper alpine) and 3210 m (subnival). Changes in species cover and richness were analysed using generalised linear mixed‐effects model (GLMMs). Results: For bryophytes, total cover remained stable overall. However, six species declined significantly between 2008 and 2022, and the species richness decreased after 2015. For terricolous lichens, total cover significantly increased on the lower alpine summit, while species richness increased on the upper alpine and subnival summits. Conclusions: Bryophytes have probably suffered from the increasingly dry conditions, with a succession of very warm and dry summers over the last decades. Terricolous lichens have taken advantage of the warmer conditions to increase their cover on the lower alpine summit, and new species have colonised the upper summits. However, as they compete with vascular plants for soil and light, they may suffer from shrub and tree encroachment in the future and will be limited upwards by the rarity of developed soils. The large topo‐climatic gradient (850 m) and the length of the time series suggest that similar trends are likely to be more widespread across the Alps. [ABSTRACT FROM AUTHOR]

Aim: Climate warming is shifting the bioclimatic optima of species towards mountaintops, but the ability of organisms to track these changes also depends on their dispersal skills. Here, we assessed the role of dispersal over niche‐driven processes in connecting assemblages along mountain slopes and between mountain massifs. Location: Cantabrian Mountains, Spain. Taxon: Birds (Animalia; Aves) and Lichens (Fungi; Ascomycota, Basidiomycota). Methods: We examined the change with elevation of community‐level traits that are dispersal proxies (wing shape in birds and type of dispersing propagule in lichens) and ecological niche proxies (micro‐habitat, substrate, and foraging features). We then permutate species composition within sites and massifs to create models of species distribution constrained by dispersal and niche processes. These models were compared with observed species distribution to disclose the relative contribution of dispersal and niche‐based processes in the biotic interchange along mountain slopes (vertical connectivity) and between isolated summits (horizontal connectivity). Results: Both bird and lichen communities were formed by species with traits that enhance dispersal at high elevations. These groups also showed similarities in the elevational patterns of niche diversity, which dropped at high elevations. Dispersal was by far the dominant assembly mechanism in both taxa. Pairwise community comparisons among elevation belts showed weak vertical connectivity, with predominant dispersal limitations but also niche barriers between the extremes of the gradient. Among massifs, horizontal connectivity was higher among high mountain assemblages than those from lower elevations. Main Conclusion: Dispersal was found to be the dominant assembly mechanism in mountain systems, even in taxa with high dispersal potential. Highland assemblages had low functional diversity but their species had high mobility. This permits biotic interchange between isolated summits and, potentially, colonization of other summits as climate warms. Our framework combining traits and occurrence‐permutation models improve the understanding of community assembly mechanisms along elevation gradients and points to dispersal limitations, especially at low‐middle elevations. [ABSTRACT FROM AUTHOR]

Parmotrema perlatum, a lichen belonging to the family Parmeliaceae, is well known for its culinary benefits and aroma used as a condiment in Indian homes is also known as the "black stone flower" or "kalpasi" in India. This research intends to analyze the antioxidant power of the crude extracts using four pH‐based buffers solubilized proteins/peptides and RP‐HPLC fractions of P. perlatum obtained by purification. The proteins that were extracted from the four different buffers were examined using LC‐MS/MS‐based peptide mass fingerprinting. When compared to the other buffers, the 0.1 M of Tris‐HCl buffer pH 8.0 solubilized proteins/peptides had the strongest antioxidant capacity. The sequential purification of the peptide was carried out by using a 3‐kDa cut‐off membrane filter and semipreparative RP‐HPLC. Additionally, the purified fractions of the peptide's antioxidant activity were assessed, and effects were compared with those of the crude and 3 kDa cut‐‐off membrane filtrates. The peptide fractions were sequenced by LC‐MS/MS, which reveals that fraction 2 from RP‐HPLC with the sequence LSWFMVVAP has shown the highest antioxidant potential in comparison with other fractions which can serve as the potential natural antioxidant drug. Further, fraction 2 also showed antibacterial activity against the selected microorganisms. [ABSTRACT FROM AUTHOR]

The Lobaria pulmonaria holobiont comprises algal, fungal, cyanobacterial and bacterial components. We investigated L. pulmonaria's bacterial microbiome in the adaptation of this ecologically sensitive lichen species to diverse climatic conditions. Our central hypothesis posited that microbiome composition and functionality aligns with subcontinental‐scale (a stretch of ~1100 km) climatic parameters related to temperature and precipitation. We also tested the impact of short‐term weather dynamics, sampling season and algal/fungal genotypes on microbiome variation. Metaproteomics provided insights into compositional and functional changes within the microbiome. Climatic variables explained 41.64% of microbiome variation, surpassing the combined influence of local weather and sampling season at 31.63%. Notably, annual mean temperature and temperature seasonality emerged as significant climatic drivers. Microbiome composition correlated with algal, not fungal genotype, suggesting similar environmental recruitment for the algal partner and microbiome. Differential abundance analyses revealed distinct protein compositions in Sub‐Atlantic Lowland and Alpine regions, indicating differential microbiome responses to contrasting environmental/climatic conditions. Proteins involved in oxidative and cellular stress were notably different. Our findings highlight microbiome plasticity in adapting to stable climates, with limited responsiveness to short‐term fluctuations, offering new insights into climate adaptation in lichen symbiosis. [ABSTRACT FROM AUTHOR]

The nomenclature and taxonomy of Acarospora molybdina is revised using morphological and molecular data. The new combination Myriospora molybdina is proposed and Acarospora hysgina is recognized as a distinct species while A. brunneola is reduced to synonymy with A. hysgina. In its new circumscription M. molybdina is an arctic species, in Scandinavia only occurring in northernmost Norway. Further localities are reported from Greenland, Russia, Svalbard and the USA (Alaska). Acarospora hysgina is the correct name for a species distributed along the west coast of Sweden and Norway, formerly thought to belong to A. molybdina. Localities are also reported from Canada (New Brunswick), Greenland and the USA (Maine). The following names are lectotypified: Acarospora brunneola, A.molybdina var. confusa, Lecanoraereutica β microcyclos, Parmelia ereutica, P. hysgina and P. molybdina. [ABSTRACT FROM AUTHOR]

A lectotype is designated for the name of the iconic and well‐known macrolichen Ramalina menziesii Taylor from among a suite of largely overlooked syntypes deposited in the Thomas Taylor Herbarium at the Farlow Herbarium, Harvard University. Lectotypes are also selected for the synonyms of R. menziesii: Chlorodictyon foliosum, Ramalina reticulata (≡ Lichen reticulatus Noehd., nom. illeg.) and R. retiformis. The place of publication of L. reticulatus Noehd. is discussed in detail. The case highlights the surprising degree to which the application of names for taxa that have been extensively studied and are widely known outside a narrow specialist field, can remain unresolved. [ABSTRACT FROM AUTHOR]

Dust is a mineral aerosol of the atmosphere that often contains trace elements such as As, Cd, and Pb. Lhù'ààn Mân' (Kluane Lake), located in southwestern Yukon, is a region of frequent dust activity. In 2016, the lake level fell due to a dramatic decrease in inflow from glacier meltwater, and the delta of the lake became an important source of dust to surrounding ecosystems. To determine the impacts of dust deposition on vegetation and soil trace element concentrations and characteristics, we sampled the lichen Peltigera canina and soil layers at 57 sites along a deposition gradient located 1.4–33.6 km downwind from the principal dust source. Arsenic, Cd, Cu, Ni and Pb in lichens were negatively correlated with the distance away from the dust source, with the highest correlations in Ni and Pb (r2 = 0.50 and 0.48, respectively). Lichen and tree abundances were negatively impacted by dust deposition, suggesting that dust can affect ecosystem vegetation composition. Starting 8 km away from the dust source, the concentrations of As, Ni, and Pb decreased by more than 50% per km, while Cd and Cu concentrations decreased by more than 40% per km. Overall, within the sampled ecosystems, soil pH is 1.4 times higher in the first 8 km from the dust source while carbon content and nutrients are lower, which implies changes in nutrient availability and cycling in dust‐affected ecosystems. Plain Language Summary: The delta of Lhù'ààn Mân' (Kluane Lake), located in southwest Yukon and on the traditional lands of Kluane First Nation, Champagne‐Aishihik First Nation, and White River First Nation, is an area where dust often settles and climate change has accelerated the melting of glaciers since the last ice age. Due to reduced glacier water flowing into the lake, the sediments in the delta are more exposed to wind, creating dust storms. To understand the impacts of dust deposition within the surrounding ecosystems, we assessed the levels of trace metals in lichens and soils across a gradient from the delta to the lake. We found that distance from the dust source affected trace metal concentrations in lichens, surface soils, and vegetation. It is essential to understand how these metals spread as they can be potentially toxic and harmful to ecosystems and humans. Key Points: Dust deposition, indicated by high trace element concentrations, is higher closest to the delta of the Ä'ą̈y Chù' into Lhù'ààn Mân'Evidence for dust deposition at Lhù'ààn Mân' can be found in trace elements of the 0–2 cm soil layer and lichens influenced by distanceVegetation characteristics are impacted by dust deposition more than soil characteristics [ABSTRACT FROM AUTHOR]

Environmental filtering and competition are two fundamental processes that shape plant community assembly in terms of functional composition, that is, the distribution of trait values. Understanding the role of these two processes in the assembly of non‐vascular vegetation, such as bryophytes and lichens, is important since these communities provide essential ecosystem services in many regions around the world, and these depend on functional composition. Responses of non‐vascular communities to environmental selection pressures have been explored in a range of experimental and modelling studies. However, it is still largely unknown to what extent competition affects the distribution of functional traits of non‐vascular communities. Moreover, it remains poorly explored which traits that are associated with competition are key for shaping community functional assembly.Here, we integrated a field transplantation experiment with a process‐based model to disentangle the effects of environmental filtering and competition on the assembly of non‐vascular communities. Following the validation of environmental selection in the model using field observations, we performed a simulation experiment to understand the impacts of competition on trait distributions in non‐vascular communities growing in two temperate locations that differ in microclimatic conditions (a shaded and an open location).Our results suggest that the functional composition is likely a result of weak competition or may not depend on competitive exclusion at all while environmental filtering plays an essential role. Plant height seems to be a key trait for competition. However, no single‐trait competition scheme could consistently explain the observed functional composition of the studied non‐vascular communities.Synthesis. The presented model provides a new trait‐based approach for simulating the functional assembly of non‐vascular communities. Environmental filtering appears to be more essential than competition for predicting trait distributions of non‐vascular communities under temperate climatic conditions and we recommend caution in associating competition to a single trait while analysing community functional assembly. [ABSTRACT FROM AUTHOR]

By providing water during the long dry rainless season, non‐rainfall water (NRW), principally dew and fog, is commonly thought to serve as an important water source for arid soil biocrusts, which require water threshold of 0.05 (for lichens) and 0.1 mm (for cyanobacteria) for growth. Such values are commonly reported in the literature. Moreover, values of >0.45 mm/d (considered as the practical theoretical threshold for dew) are also reported. Following an analysis of limited (29 days) dewy mornings, it was recently reported that dew is incapable of forming on the soil surface. Being of limited scope, we therefore analyse days that yielded the highest amounts of NRW during 2 years (2021–2023) of measurements (22 days with NRW ≥0.15 mm). We conducted measurements at 1 m above ground, cobbles, rocks, and the soil surface, and compared them to the cloth‐plate method. Additionally, periodical temperature measurements were conducted, and the dewpoint temperature (Td) was calculated. Our findings indicate that (a) dew yield never surpassed 0.4 mm, (b) while the water threshold amounts were reached on the rocks and especially on the cobbles, these thresholds were seldom reached on soil (a single morning with 0.1 mm and 3 days with ≥0.05 mm), (c) in comparison to air temperatures at 0.05 m and especially at 1 m‐height above ground, surface nocturnal soil temperatures were 2–3°C warmer, thus eliminating possible vapour condensation. Our data cast doubt on values of >0.45 mm reported from various deserts. Additionally, while supporting the view that NRW may provide water for the growth of rock‐dwelling lichens, NRW in the Negev does not provide the soil biocrusts with sufficient water for growth. [ABSTRACT FROM AUTHOR]

This research explores an environmentally friendly alternative: lichens, which produce natural compounds with antioxidant effects. This study focuses on the inhibition of corrosion by lichens, which has not been previously explored for this purpose. The anti‐corrosion potential of methanol extracts of Parmotrema hypoleucinum, Roccella phycopsis, and Xanthoria parietina was examined. The electrochemical impedance and weight loss methods were used to examine the corrosion inhibition process of mild steel XC48 in 1 M HCl by three lichen extracts. [ABSTRACT FROM AUTHOR]

To date (1 November 2023), the online database AlgaeBase has documented 50,589 species of living algae and 10,556 fossil species here referred to four kingdoms (Eubacteria, Chromista, Plantae, and Protozoa), 14 phyla, and 63 classes. The algae are the third most speciose grouping of plant‐like organisms after the flowering plants (≈382,000 species) and fungi (≈170,000 species, including lichens) but are the least well defined of all the botanical groupings. Priority is given to phyla and class names that are familiar to phycologists and that are nomenclaturally valid. The most species‐rich phylum is the Heterokontophyta to which 18 classes are referred with 21,052 living species and which is dominated by the diatoms in three classes with 18,673 species (16,427 living; 2239 fossil). The next most species‐rich phyla are the red algae (7276 living), the green algae (6851 living), the blue‐green algae (Cyanobacteria, 5723 living), the charophytes (4950 living, including the Charophyceae, 511 species living, and the Zygnematophyceae, 4335 living species), Dinoflagellata (2956 living, including the Dinophyceae, 2828 extant), and haptophytes (Haptophyta 1722 species, 517 living). [ABSTRACT FROM AUTHOR]

This study aimed to comprehensively assess the antimicrobial, antifouling, and antibiofilm‐forming potential of lichen symbiotic bacteria against marine fouling bacterial strains. A total of 50 lichen‐associated bacteria (LAB) isolates were successfully characterized and evaluated for their effectiveness in mitigating biofouling caused by various marine biofoulers. Through a battery of biological assays encompassing enzymatic, antagonistic, antimicrobial, and antifouling assays, 15 LAB isolates were identified based on their antagonist activities. Notably, the strain LAB4 exhibited remarkable performance across all bioassays, demonstrating its proficiency as an antifouling agent. The production of crude LAB extracts was successfully scaled up using a large‐scale fermentor and further optimized. Additionally, a phylogenetic analysis of the isolated strain Bacillus proteolyticus D65's 16S ribosomal RNA gene revealed a high query coverage and percentage identity of 92.62% (accession no. MK883171.1). In conclusion, the lichen bacterial symbiotic isolate B. proteolyticus exhibited significant in vitro and in vivo inhibition of foulants. This study highlights the potential of lichens as a valuable source of yet unexplored bacteria. The bacterial consortium associated with Parmotrema sp. holds promise in combatting biofouling, which poses a substantial threat to the maritime industries and their economic stability. [ABSTRACT FROM AUTHOR]

Premise: Methods to evaluate lichen thalli hydrophobicity have previously been described, but only recently has hydrophobicity been shown to be an important functional trait related to water regulation dynamics that could be used to predict future climate change effects. We describe a novel protocol to measure lichen thallus hydrophobicity that aims to be an easier and more affordable approach. Methods and Results: Our protocol requires only a micropipette, distilled water, a tripod, and a smartphone or camera. Hydrophobicity is inferred from multiple metrics associated with the absorption times of standardized droplets (initial and total absorption time). We used a data set of 93 lichen taxa with different growth forms and from different biomes and demonstrated that this method is well suited for capturing different levels of hydrophobicity, including very hydrophilic species. Conclusions: Our results show that this new protocol to measure lichen hydrophobicity is a rapid and low‐cost method to assess an ecophysiologically based functional trait that can be used with almost no limitations, including in different climates, lichen species, and growth forms. [ABSTRACT FROM AUTHOR]

Lichens are combinations of two symbiotic organisms, a green alga or cyanobacterium and a fungus. They grow in nearly all terrestrial ecosystems and survive in habitats, which are very dry or cold, or too poor in nutrients to maintain vegetation growth. Because lichens grow on visible surfaces and exhibit spectral properties, which are clearly different from, for example, vegetation, it is possible to distinguish them in remote sensing data. In this first systematic review article on remote sensing of lichens, we analyze and summarize which lichen species or genera, and in which habitats and geographical regions, have been remotely sensed, and which remote sensing or spectroscopic technologies have been used. We found that laboratory or in situ measured spectra of over 70 lichen species have been reported to date. We show that studies on remote sensing of lichens fall under seven broad themes: (1) collection of lichen spectra for quantification of lichen species or characteristics, (2) pollution monitoring with lichens as ecological indicators, (3) geological and lithological mapping, (4) desert and dryland monitoring, (5) animal habitat monitoring, (6) land cover or vegetation mapping, and (7) surface energy budget modeling. [ABSTRACT FROM AUTHOR]

Question: What are the extent and the possible causes of imperfect detection in lichens? Because lichens are sessile and lack seasonality, they should be easier to survey than animals that can move or plants and fungi with seasonal morphology, and one could therefore expect relatively high detection probabilities. Location: 826 standardised sampling plots across Switzerland. Methods: Using repeated detection/non‐detection data from a national lichen survey conducted by professional lichenologists, we estimated the mean and variation in detectability for 373 tree‐living species with a multi‐species occupancy model. We also quantified the effect of species conspicuousness, identifiability and observer experience on detection probability. Results: The average detection probability for a single survey was unexpectedly low with an average of 0.49 (range across species: 0.25–0.74). Conspicuous species showed higher average detectability (0.56) than inconspicuous species (0.41), and identifiability as well as previous experience with a species substantially increased the probability of a person detecting it. Accounting for experience, the mean detection probabilities of observers ranged from 0.32 to 0.69. Conclusions: Our study confirms that detection probability per survey is often far below 1 also in sessile organisms, even when a standardised survey is conducted by experts. When species are seasonal (plants, fungi, etc.), survey areas are larger, or field personnel are less experienced, as is the case for many surveys and monitoring programs, detectabilities are likely to be substantially lower. We therefore argue that imperfect detection should systematically be considered in the survey design and data analysis also for sessile organisms. [ABSTRACT FROM AUTHOR]

Summary: Lichens are exemplar symbioses based upon carbon exchange between photobionts and their mycobiont hosts. Historically considered a two‐way relationship, some lichen symbioses have been shown to contain multiple photobiont partners; however, the way in which these photobiont communities react to environmental change is poorly understood.Lichina pygmaea is a marine cyanolichen that inhabits rocky seashores where it is submerged in seawater during every tidal cycle. Recent work has indicated that L. pygmaea has a complex photobiont community including the cyanobionts Rivularia and Pleurocapsa. We performed rRNA‐based metabarcoding and mRNA metatranscriptomics of the L. pygmaea holobiont at high and low tide to investigate community response to immersion in seawater.Carbon exchange in L. pygmaea is a dynamic process, influenced by both tidal cycle and the biology of the individual symbiotic components. The mycobiont and two cyanobiont partners exhibit distinct transcriptional responses to seawater hydration.Sugar‐based compatible solutes produced by Rivularia and Pleurocapsa in response to seawater are a potential source of carbon to the mycobiont. We propose that extracellular processing of photobiont‐derived polysaccharides is a fundamental step in carbon acquisition by L. pygmaea and is analogous to uptake of plant‐derived carbon in ectomycorrhizal symbioses. See also the Commentary on this article by Grube & Balestrini, 241: 1888–1890. [ABSTRACT FROM AUTHOR]

Cover Legend The marine lichen Lichina pygmaea at low tide in the eulittoral zone of the shore, Plymouth Hoe. Image courtesy of Chris Parkes, Marine Biological Association (Chrismas et al., pp. 2243–2257). [Extracted from the article]

Atmospheric pollution containing soil‐nitrifying ammonium sulfate ((NH₄)₂SO₄) affects semi‐natural ecosystems worldwide. Long‐term additions of (NH₄)₂SO₄ to nitrogen (N)‐limited habitats, including heathlands, increase climate stress affecting recovery from wildfires. Although heathland vegetation largely depends on ericoid mycorrhizal fungi (ErM) to access soil N, we lack detailed understanding of how prolonged exposure to (NH₄)₂SO₄ may alter ErM community composition and host plants' reliance on fungal partners following wildfire and affect recovery. Simulation of atmospheric pollution ((NH₄)₂SO₄) occurred bi‐weekly for 5 years after a 2006 wildfire in a UK heathland. Ten years after treatments ceased, we measured vegetation structure, lichen and lichen photobiont composition, soil characteristics, ErM colonization, ErM diversity in roots and soil, and assessed ErM potential as novel recovery indicators. Heather height and density, and moss groundcover, were greater in N‐enriched plots. Lichen community indices showed significant treatment effects, but without differences in photobionts. Soil pH and Mg were significantly lower in treated plots while soil cation exchange capacity was significantly higher. There were no detectable differences in ErM composition and keystone ErM taxa between control and treated plots. Soil carbon stock measures were variable. Our results indicate atmospheric pollution following fire can have significant lingering effects above‐ and belowground. ErM diversity and root colonization were not assessed in the original N‐addition experiment; we advocate for their inclusion in future studies as an integral part of the recovery assessment toolkit. We show that mycorrhizal fungi diversity is a viable ecological tool and summarize key steps for ErM identification. [ABSTRACT FROM AUTHOR]

Biofouling poses a significant economic challenge for marine transportation. The use of chemical compounds to eliminate fouling layers beneath the ship's surface, albeit effective, raises concerns due to its potential harm to the aquatic ecosystem. Lichen symbiotic associations, an underexplored research area, show promise in producing antimicrobial and antifouling compounds. These lichen‐associated bacteria engage in various functional activities and have multiple bacterial counterparts. The optimal conditions for cultivating lichen‐associated bacteria for maximum growth were identified as a pH of 7, a temperature of 30°C, and an incubation period of 8 days. Glucose served as the carbon source, while yeast extract served as the nitrogen source. Additionally, zinc nanoparticles were successfully synthesized from the thriving lichen‐associated bacteria. Fourier transform infrared spectroscopy (FTIR) analysis indicated distinctive bands at 3890 and 3103 cm−1, corresponding to the OH stretching of alcohol and acid stretch bands, respectively. Furthermore, the presence of amide in NH banding in the synthesized zinc nanoparticles was represented by a band at 1636 cm−1. SEM images of the produced zinc NPs displayed a spherical shape, ranging in size from 40 to 70 nm. To assess the impact of these nanoparticles from lichen‐associated bacteria on biofouling activity in marine transportation, zebrafish results were analyzed. [ABSTRACT FROM AUTHOR]

Circadian regulation is linked to local environmental adaptation, and many species with broad climatic niches display variation in circadian genes. Here, we hypothesize that lichenizing fungi occupying different climate zones tune their metabolism to local environmental conditions with the help of their circadian systems. We study two species of the genus Umbilicaria occupying similar climatic niches (Mediterranean and the cold temperate) in different continents. Using homology to Neurospora crassa genes, we identify gene sets associated with circadian rhythms (11 core, 39 peripheral genes) as well as temperature response (37 genes). Nucleotide diversity of these genes is significantly correlated with mean annual temperature, minimum temperature of the coldest month and mean temperature of the coldest quarter. Furthermore, we identify altitudinal clines in allele frequencies in several non‐synonymous substitutions in core clock components, for example, white collar‐like, frh‐like and various ccg‐like genes. A dN/dS approach revealed a few significant peripheral clock‐ and temperature‐associated genes (e.g. ras‐1‐like, gna‐1‐like) that may play a role in fine‐tuning the circadian clock and temperature‐response machinery. An analysis of allele frequency changes demonstrated the strongest evidence for differentiation above the genomic background in the clock‐associated genes in U. pustulata. These results highlight the likely relevance of the circadian clock in environmental adaptation, particularly frost tolerance, of lichens. Whether or not the fungal clock modulates the symbiotic interaction within the lichen consortium remains to be investigated. We corroborate the finding of genetic variation in clock components along altitude—not only latitude—as has been reported in other species. [ABSTRACT FROM AUTHOR]

Interactions between organisms are determined by life‐history traits. Ecological strategies regarding species specialisation range from generalist to highly specialised relationships. Although it is expected that habitat fragmentation's effect on species abundance and survival depends on their degree of specialisation and life‐history traits, few studies have delved into the interplay between interaction specialisation, life‐history traits and habitat fragmentation.Here, we investigate the combined effect of habitat fragmentation, forest structure and life‐history traits (growth form and reproductive mode) on the specialisation of lichen‐forming fungi (mycobionts) toward their photosynthetic partners (photobionts) in lichen symbioses.We studied mycobiont specialisation in epiphytic lichen communities present in 10 fragments of Quercus rotundifolia forest embedded in an agricultural matrix. Both mycobionts and photobionts were identified DNA barcoding and mycobiont specialisation was measured through interaction parameters calculating the relative number of interactions (normalised degree; ND) and the specialisation of each species based on its discrimination from a random selection of partners (d'). Phylogenetic generalised linear mixed models were used to analyse the effect of patch size as well as the life history traits growth form (crustose, foliose, fruticose) and reproduction mode (sexual vs. asexual) on mycobiont specialisation.Both mycobiont and photobiont richness along the patch size gradient followed a hump‐back pattern, which was more pronounced in photobionts. Mycobionts forming crustose thalli established the largest number of interactions. Mycobiont specialisation (d') was larger for fruticose and foliose forms and species with vegetative reproduction. Along the gradient of fragment size, the relative number of interactions decreased and the specialisation of mycobionts with vegetative reproduction increased.Synthesis. The study of mycobiont specialisation towards their photobionts in epiphytic lichen communities in a fragmented Mediterranean forest revealed a complex interaction between species' life history traits and habitat fragmentation. In particular, this interplay had a significant impact on the specialisation of mycobionts. The results show the ability of some species to modulate their specialisation according to habitat conditions, suggesting that some species may be more resilient to abiotic changes than expected. [ABSTRACT FROM AUTHOR]

Premise: Bryophytes and lichens have important functional roles in many ecosystems. Insight into their CO2‐exchange responses to climatic conditions is essential for understanding current and predicting future productivity and biomass patterns, but responses are hard to quantify at time scales beyond instantaneous measurements. We present PoiCarb 1.0, a model to study how CO2‐exchange rates of these poikilohydric organisms change through time as a function of weather conditions. Methods: PoiCarb simulates diel fluctuations of CO2 exchange and estimates long‐term carbon balances, identifying optimal and limiting climatic patterns. Modelled processes were net photosynthesis, dark respiration, evaporation and water uptake. Measured CO2‐exchange responses to light, temperature, atmospheric CO2 concentration, and thallus water content (calculated in a separate module) were used to parameterize the model's carbon module. We validated the model by comparing modelled diel courses of net CO2 exchange to such courses from field measurements on the tropical lichen Crocodia aurata. To demonstrate the model's usefulness, we simulated potential climate‐change effects. Results: Diel patterns were reproduced well, and the modelled and observed diel carbon balances were strongly positively correlated. Simulated warming effects via changes in metabolic rates were consistently negative, while effects via faster drying were variable, depending on the timing of hydration. Conclusions: Reproducing weather‐dependent variation in diel carbon balances is a clear improvement compared to simply extrapolating short‐term measurements or potential photosynthetic rates. Apart from predicting climate‐change effects, future uses of PoiCarb include testing hypotheses about distribution patterns of poikilohydric organisms and guiding conservation strategies for species. [ABSTRACT FROM AUTHOR]

The present study aims to explore the inhibitory action of lichen metabolites against important protein targets of marine fouling organisms using computational methods. Lichens with their unique ability to produce various secondary metabolites find versatile applications in Biotechnology and allied fields. The 3D structure of target proteins associated with fouling activity of marine organism were collected from the protein data bank (PDB) and the computational docking analysis was performed using the PyRx software with 40 lichen compounds that are collected from PubChem. The lichen compounds were docked against the following protein targets—mannose‐specific lectin CGL1 of Crassostrea gigas, Proximal thread matrix protein 1 PTMP 1 of Mytilus galloprovincialis, and G protein‐coupled receptor (GPCR) of Balanus amphitrite. As there was no experimentally determined structure available for GPCR of B. amphitrite, homology modeling was performed to predict the protein structure. The docking study showed effective binding of lichen compounds to various fouling targets with the binding energies in the range of −10.1 to −5 kcal/mol. Among the lichen compounds studied, roccanin showed the least binding energy for CGL1, PTMP1 and GPCR. The correlation assessments predict a positive relationship between binding energy, molecular weight and retention time. MD Simulation studies were performed using LARMD online tool and the RMSD and radius of gyration (Rg) values was recorded. This study proves that the compounds produced by lichens have high antifouling effect against marine foulers under in silico conditions. [ABSTRACT FROM AUTHOR]

The term 'succession' was first proposed to describe the gradual development of plants from an initial stage such as a bare ground to a well‐developed plant community, which at its peak, may reach a climax (primary succession). Accordingly, the earlier and fast growing stage (such as an annual plant community) may grant stability, organic matter and nutrients to the latter, high‐biomass and slow‐growing stages, such as trees. Commonly, reference to the different successional stages is also made once intact and disturbed communities (such as due to mechanical disturbance, tillage, fire, etc.) are compared (secondary succession). The concept was borrowed by many ecologists to describe variable biocrust types. Cyanobacterial or algal biocrust is regarded as an initial stage before turning to a later, more mature biocrust, whether composed of lichens or mosses. The underlain assumptions are that (a) the cyanobacteria provide essential stability and (b) nutrients that are required for the development of the later stages; (c) the initial biocrusts improve the water regime for the later successional stages; (d) cyanobacteria promote the lichen symbiosis; (e) due to substantial differences in the recovery time, a linear succession is inevitable, commonly from cyanobacterial/alga to lichen and lastly to moss; and (f) the cyanobacterial/algal biocrust is a temporary stage, just before being outcompeted by a later stage. It is argued hereafter that the above‐mentioned assumptions are not necessarily correct. As with higher plants, unless a direct comparison between disturbed and intact crusts justifies a reference to successional stages, different types of biocrusts commonly reflect the abiotic conditions at their site, and as such, unless the abiotic conditions change, they reflect stable communities of variable crust types. This paradigm shift may have important implications regarding inoculation efforts and directions and may explain the low success thus far obtained following inoculation experiments once performed with the more developed biocrusts, lichens and mosses. [ABSTRACT FROM AUTHOR]

Pseudomonas syringae is a bacterial complex that is widespread through a range of environments, typically associated with plants where it can be pathogenic, but also found in non‐plant environments such as clouds, precipitation, and surface waters. Understanding its distribution within the environment, and the habitats it occupies, is important for examining its evolution and understanding behaviours. After a recent study found P. syringae living among a range of vascular plant species in Iceland, we questioned whether lichens could harbour P. syringae. Sixteen different species of lichens were sampled all over Iceland, but only one lichen genus, Peltigera, was found to consistently harbour P. syringae. Phylogenetic analyses of P. syringae from 10 sampling points where lichen, tracheophyte, and/or moss were simultaneously collected showed significant differences between sampling points, but not between different plants and lichens from the same point. Furthermore, while there were similarities in the P. syringae population in tracheophytes and Peltigera, the densities in Peltigera thalli were lower than in moss and tracheophyte samples. This discovery suggests P. syringae strains can localize and survive in organisms beyond higher plants, and thus reveals opportunities for studying their influence on P. syringae evolution. [ABSTRACT FROM AUTHOR]

Holobionts are dynamic ecosystems that may respond to abiotic drivers with compositional changes. Uncovering elevational diversity patterns within these microecosystems can further our understanding of community‐environment interactions. Here, we assess how the major components of lichen holobionts—fungal hosts, green algal symbionts, and the bacterial community—collectively respond to an elevational gradient. We analyse populations of two lichen symbioses, Umbilicaria pustulata and U. hispanica, along an elevational gradient spanning 2100 altitudinal metres and covering three major biomes. Our study shows (i) discontinuous genomic variation in fungal hosts with one abrupt genomic differentiation within each of the two host species, (ii) altitudinally structured bacterial communities with pronounced turnover within and between hosts, and (iii) altitude‐specific presence of algal symbionts. Alpha diversity of bacterial communities decreased with increasing elevation. A marked turnover in holobiont diversity occurred across two altitudinal belts: at 11°C–13°C average annual temperature (here: 800–1200 m a.s.l.), and at 7°C–9°C average annual temperature (here: 1500–1800 m a.s.l.). The two observed zones mark a clustering of distribution limits and community shifts. The three ensuing altitudinal classes, that is, the most frequent combinations of species in holobionts, approximately correspond to the Mediterranean, cool‐temperate, and alpine climate zones. We conclude that multitrophic microecosystems, such as lichen holobionts, respond with concerted compositional changes to climatic factors that also structure communities of macroorganisms, for example, vascular plants. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Mycosis fungoides is a diagnostic challenge. Herein, we report a case with marked lichenoid features in pathology assessments. After several biopsies and clinicopathologic correlation, the diagnosis of lichenoid mycosis fungoides was made. Mycosis fungoides (MF) is a great imitator and mimicks other dermatoses clinically and histopathologically. We report a 61‐year‐old patient with 5‐year history of generalized violaceous patches and plaques. His biopsy revealed a marked lichenoid band‐like infiltrate of inflammatory cells along the basal layer with basal layer vacuolar changes; the diagnosis of lichen planus was first made histopathologically. Several biopsy specimens, clinicopathologic correlation, and immunohistochemistry findings confirmed the diagnosis of lichenoid MF. Awareness of peculiar histopathologic findings of MF is essential to avoid a potential misdiagnosis. When in doubt, multiple biopsies with other diagnostic methods should be employed. [ABSTRACT FROM AUTHOR]

The great extension of forests in the Djebel El Ghorra massif of El Kala National Park (north‐eastern Algeria) allowed us to recognise three distinct forest formations: cork oak stands (Quercus suber), zeen oak stands (Quercus canariensis) and mixed oak (Quercus suber and Quercus canariensis) forest. Their peculiarities showed ideal ecological characteristics for the colonisation of corticolous lichens the two phorophytes. The three forest formations were sampled between 2017 and 2022. The identification of the taxa is based on stereo‐microscopic examinations and usual chemical tests. Systematic surveys were conductedand allowed us to establish a list of 141 lichen taxa divided into 30 families. [ABSTRACT FROM AUTHOR]

Summary: Information on appointments to the Fungal Nomenclature Bureau is provided. Appointments to two Special‐purpose Committees are reported. The following four generic names are recommended for conservation: Bilimbia with a conserved type; Coccotrema against Lepolichen; Fuscidea against Maronea; and Leptogium (lichenized Ascomycota) with a conserved type. The following two generic names are not recommended for conservation: Marcelaria against Buscalionia; and Variolaria Pers. against Lepra and Variolaria Bull. The following seven species names are recommended for conservation: Lecidea parmeliarum (Abrothallus parmeliarum) against Endocarpon parasiticum; Lichen cervinus (Acarospora cervina) with a conserved type; L. ferrugineus (Blastenia ferruginea) with a conserved type; L. flavus Bellardi (Pleopsidium flavum) against L. flavus Schreb.; Megaspora verrucosa (Ach.) Arcadia & A. Nordin against M. verrucosa Hafellner & V. Wirth.; Umbilicaria spodochroa with a conserved type and with that spelling; and Usnea fulvoreagens with a conserved type. The following three species names are not recommended for conservation: Alectoria fuscescens (Bryoria fuscescens), nom. cons., against the additional names Usnea implexa, A. capillaris, A. cana, A. rubens, A. fuscidula, A. degenii, A. forissii, A. ostrobotniae, A. kuemmerleana, A. haynaldiae, A. achariana, A. lanestris, A. prostratosteola, and A. viridescens; Lichen fuscovirens (Collema fuscovirens) against L. pulcher; and Ochrolechia szatalaensis against Pertusaria poriniza. The following two species names are recommended for rejection under Art. 56: Lecidea cornea and Lichen conspurcatus. The following generic name is recommended for rejection under Art. 56: Huea (and the original proposal to conserve Huea with a conserved type is not recommended). It is recommended that the species name Variolaria torta not be rejected under Art. 56. The proposal to conserve Pertusariaceae against Variolariaceae is considered unnecessary because the latter name is illegitimate. The Nomenclature Committee for Fungi could not arrive at a recommendation on the proposal to conserve Lagerheimia (De Toni) Chodat against Lagerheima Sacc. and nor resolve requests for binding decisions on whether the pair Geisleria Nitschke and Geissleria Lange‐Bert. & Metzeltin and the pair Lagerheima Sacc. and Lagerheimia (De Toni) Chodat are sufficiently alike to be confused – but these three items have now been resolved by the General Committee. [ABSTRACT FROM AUTHOR]

This article discusses a study that examines the selection of host microbiota in arid desert lichen crusts. The researchers focused on a specific type of lichen called Endocarpon and analyzed the bacterial communities in four different layers of the lichen. The study found that the bacteria in the lichen primarily come from the soil, indicating a clear preference for specific hosts. These findings provide valuable insights into how lichen symbionts maintain a balanced relationship and how the lichen community forms in desert environments. The study also identified important bacterial species that contribute to the lichen microbiota. Overall, this research enhances our understanding of how lichens function and interact with their environment. [Extracted from the article]

Aim: Lichens are often regarded as paradigms of mutualistic relationships. However, it is still poorly known how lichen‐forming fungi and their photosynthetic partners interact at a community scale. We explored the structure of fungus‐alga networks of interactions in lichen communities along a latitudinal transect in continental Antarctica. We expect these interactions to be highly specialized and, consequently, networks with low nestedness degree and high modularity. Location: Transantarctic Mountains from 76° S to 85° S (continental Antarctica). Time Period: Present. Major Taxa Studied: Seventy‐seven species of lichen‐forming fungi and their photobionts. Methods: DNA barcoding of photobionts using nrITS data was conducted in 756 lichen specimens from five regions along the Transantarctic Mountains. We built interaction networks for each of the five studied regions and a metaweb for the whole area. We explored the specialization of both partners using the number of partners a species interacts with and the specialization parameter d'. Network architecture parameters such as nestedness, modularity and network specialization parameter H2' were studied in all networks and contrasted through null models. Finally, we measured interaction turnover along the latitudinal transect. Results: We recovered a total of 842 interactions. Differences in specialization between partners were not statistically significant. Fungus‐alga interaction networks showed high specialization and modularity, as well as low connectance and nestedness. Despite the large turnover in interactions occurring among regions, network parameters were not correlated with latitude. Main Conclusions: The interaction networks established between fungi and algae in saxicolous lichen communities in continental Antarctica showed invariant properties along the latitudinal transect. Rewiring is an important driver of interaction turnover along the transect studied. Future work should answer whether the patterns observed in our study are prevalent in other regions with milder climates and in lichen communities on different substrates. [ABSTRACT FROM AUTHOR]

Lung cancer is the leading cause of cancer‐related deaths all over the world. Therefore, it has gained importance in the development of new chemotherapeutic strategies to identify anticancer agents with low side effects, reliable, high anticancer potential, and specific to lung cancer cells. Thioredoxin reductase 1 (TrxR1) is an important therapeutic target for lung cancer treatment because of its overexpression in tumor cells. Here, we aimed to examine the anticancer effect of diffractaic acid, a lichen secondary metabolite, in A549 cells by comparing it with the commercial chemotherapeutic drug carboplatin and also to investigate whether the anticancer effect of diffractaic acid occurs via TrxR1‐targeting. The IC50 value of diffractaic acid on A549 cells was determined as 46.37 μg/mL at 48 h, and diffractaic acid had stronger cytotoxicity than carboplatin in A549 cells. qPCR results revealed that diffractaic acid promoted the intrinsic apoptotic pathway through the upregulation of the BAX/BCL2 ratio and P53 gene in A549 cells, which is consistent with the flow cytometry results. Furthermore, migration analysis results indicated that diffractaic acid impressively suppressed the migration of A549 cells. While the enzymatic activity of TrxR1 was inhibited by diffractaic acid in A549 cells, no changes were seen in the quantitative expression levels of gene and protein. These findings provide fundamental data on the anticancer effect of diffractaic acid on A549 cells targeting TrxR1 activity, suggesting that it could be considered a chemotherapeutic agent for lung cancer therapy. Our previous study revealed that diffractaic acid inhibited mitochondrial TrxR purified from rat lung. In this study, we examined the cytotoxic, apoptotic, and migratory effects of diffractaic acid in lung cancer A549 cell line and also determined whether these effects were mediated through TrxR1 targeting. The results exhibited that diffractaic acid performed anticancer effects by inhibiting TrxR1 activity. Thereby, diffractaic acid may be a novel TrxR1 inhibitor and a potent chemotherapeutic agent for lung cancer. [ABSTRACT FROM AUTHOR]

One of the most commonly occurring bacteria, Bacillus subtilis, can produce a wide variety of secondary metabolites. In this study, the antimicrobial effect of B. subtilis KSRLAB3 against Vibrio alginolyticus was optimized using the Plackett–Burman design (PBD) method, response surface methodology (RSM), and genetic algorithm (GA). Initially, the effects of carbon source, nitrogen source, NaCl concentration, pH, temperature, and incubation time on antimicrobial effects were studied. Among the carbon and nitrogen sources investigated, mannose and peptone elicited maximum antimicrobial effect. Using PBD, the most significant variables that influence the antimicrobial effect were identified, including incubation time, peptone concentration, and temperature. The optimum conditions required for attaining maximum antimicrobial effect was identified using the RSM‐GA hybrid method, and the optimum condition includes 49.999 h of incubation time, 4.39 g/L of peptone concentration, and 27.629°C of incubation temperature. The confirmatory experiments performed around the optimum condition showed a zone of inhibition of 35 ± 0.52 mm. Methanolic extract also proved the presence of antibacterial lipopeptide surfactin. Therefore, the RSM‐GA hybrid method was successfully used in this study to model the antimicrobial effect of B. subtilis KSRLAB3 against V. alginolyticus. The effective inhibition of V. alginolyticus can be investigated further for the development of antifouling coatings. [ABSTRACT FROM AUTHOR]

This article is a Commentary on Chrismas et al. (2024), 241: 2243–2257. [ABSTRACT FROM AUTHOR]

The article discusses the current proposals to redefine lichens and highlights the disadvantages of these proposals. Lichens are currently defined as a symbiotic relationship between a fungus (mycobiont) and an alga or cyanobacterium (photobiont). However, some lichen biologists have suggested expanding this definition to include other microorganisms that colonize the lichen thallus. The article argues that these proposals are not justified because the roles and significance of these additional microorganisms are still poorly understood and their inclusion would blur the distinction between lichens and other ecosystems. The article concludes that the current definition of lichens as a partnership between mycobiont and photobiont remains meaningful and should not be amended. [Extracted from the article]

[Lichens are a] highly successful yet confounding entity. " Twelve Readings on the Lichen Thallus." http://www.waysofenlichenment.net. - Honegger ([4]) To me the real conceptual challenge posed by the lichen thallus derives from its unsettling capacity for transmutation even at the slightest shift in perspective.... Lichens ... exist at a kind of conceptual doorway, a portal. [Extracted from the article]

This study focused on the taxonomic evaluation of the genus Verrucaria Shrad (Ascomycota, Verrucariaceae) in northeast Iran. Lichen samples were collected from the Khorasan Razavi province and their morphological, anatomical, and ecological characteristics were investigated. According to the result, the species Verrucaria ahtii Pykälä, Launis and Myllys, Verrucaria cataleptoides (Nyl.) Nyl., Verrucaria dolosa Hepp., Verrucaria hochstetteri Fr., and Verrucaria muralis Ach., are new records from Iran. [ABSTRACT FROM AUTHOR]

Premise: Little is known about the ability of individual species to grow successfully outside of their realized niche. Here, the vitality of two epiphytic bryophyte and two epiphytic lichen species were assessed in their fundamental and realized niches in the Pacific Northwest coniferous forest at low, mid, and high elevations. Methods: Two lowland epiphytic bryophyte species (Frullania nisquallensis, Neckera douglasii) and one lowland epiphytic lichen species (Usnea longissima) were transplanted to sites at mid and high elevations. One high‐elevation epiphytic lichen species (Hypogymnia rugosa) was transplanted to mid and low elevations. Results: The fundamental and realized niches of F. nisquallensis and U. longissima are similar, and they can both survive outside of their realized niches. For N. douglasii, dispersal limitations could shape its distribution along elevation and local microclimate conditions could be important for its vitality. Conclusions: Certain bryophyte and lichen species can survive outside of their realized niches, information that can contribute to knowledge about species niches along elevational gradients. Future studies should focus on cryptogam species interactions in a changing climate. [ABSTRACT FROM AUTHOR]

Habitat loss is considered a major threat for biodiversity. However, the scales on which its effects occur are still insufficiently understood, namely, is the amount of available habitat important for species richness on both local and landscape scales? We studied the effects of local and landscape‐scale habitat amount on local‐scale species density of deadwood‐dependent lichens in Swedish boreal forests. Creation and retention of deadwood are common practices to benefit forest biodiversity, and recognizing the relevant scale is critical for them to be successful.We surveyed deadwood‐dependent lichens in 90 unmanaged forest stands that differed in the local and landscape habitat amount. The local habitat amount was measured as the amount of deadwood in the sampled stands (m2 deadwood ha−1), while six alternative proxies were used to estimate the landscape habitat amount, that is, the amount of deadwood in the surrounding landscapes. Lichen species density (number of species per standardized deadwood area of 3.7 m2) was modelled as a function of local and landscape habitat amount at multiple scales (300 m–5 km from the stands).Lichen species density increased with the landscape habitat amount. The proportion of old forests (>100 years, including newly clear‐cut stands that until recently were old forests) within 5 km from the stands explained species density better than the other proxies of landscape habitat amount. Local deadwood amount did not affect species density, and there was no interaction between the local and landscape habitat amount.Synthesis and applications: To promote the conservation of deadwood‐dependent lichens, the amount of old forests in managed forest landscapes should be maintained or increased. A certain amount of deadwood hosted more lichen species when situated in a landscape with more old forest, while there was no effect of the local deadwood amount. This suggests that management aimed at increasing the local species density of deadwood‐dwelling lichens should focus on creating and maintaining habitat in the surrounding landscape rather than only adding deadwood to that local site. In other words, effective management for deadwood‐dependent lichen diversity requires landscape‐scale habitat protection. [ABSTRACT FROM AUTHOR]

Specialization, contextualized in a resource axis of an organism niche, is a core concept in ecology. In biotic interactions, specialization can be determined by the range of interacting partners. Evolutionary and ecological factors, in combination with the surveyed scale (spatial, temporal, biological, and/or taxonomic), influence the conception of specialization. This study aimed to assess the specialization patterns and drivers in the lichen symbiosis, considering the interaction between the principal fungus (mycobiont) and the associated Nostoc (cyanobiont), from a community perspective considering different spatial scales. Thus, we determined Nostoc phylogroup richness and composition of lichen communities in 11 Nothofagus pumilio forests across a wide latitudinal gradient in Chile. To measure specialization, cyanobiont richness, Simpson's and d′ indices were estimated for 37 mycobiont species in these communities. Potential drivers that might shape Nostoc composition and specialization measures along the environmental gradient were analysed. Limitations in lichen distributional ranges due to the availability of their cyanobionts were studied. Turnover patterns of cyanobionts were identified at multiple spatial scales. The results showed that environmental factors shaped the Nostoc composition of these communities, thus limiting cyanobiont availability to establish the symbiotic association. Besides, specialization changed with the spatial scale and with the metric considered. Cyanolichens were more specialized than cephalolichens when considering partner richness and Simpson's index, whereas the d′ index was mostly explained by mycobiont identity. Little evidence of lichen distributional ranges due to the distribution of their cyanobionts was found. Thus, lichens with broad distributional ranges either associated with several cyanobionts or with widely distributed cyanobionts. Comparisons between local and regional scales showed a decreasing degree of specialization at larger scales due to an increase in cyanobiont richness. The results support the context dependency of specialization and how its consideration changes with the metric and the spatial scale considered. Subsequently, we suggest considering the entire community and widening the spatial scale studied as it is crucial to understand factors determining specialization. [ABSTRACT FROM AUTHOR]