Abstract: Studies of biological soil crusts (biocrusts) have proliferated over the last few decades. The biocrust literature has broadened, with more studies assessing and describing the function of a variety of biocrust communities in a broad range of biomes and habitats and across a large spectrum of disciplines, and also by the incorporation of biocrusts into global perspectives and biogeochemical models. As the number of biocrust researchers increases, along with the scope of soil communities defined as ‘biocrust’, it is worth asking whether we all share a clear, universal, and fully articulated definition of what constitutes a biocrust. In this review, we synthesize the literature with the views of new and experienced biocrust researchers, to provide a refined and fully elaborated definition of biocrusts. In doing so, we illustrate the ecological relevance and ecosystem services provided by them. We demonstrate that biocrusts are defined by four distinct elements: physical structure, functional characteristics, habitat, and taxonomic composition. We describe outgroups, which have some, but not all, of the characteristics necessary to be fully consistent with our definition and thus would not be considered biocrusts. We also summarize the wide variety of different types of communities that fall under our definition of biocrusts, in the process of highlighting their global distribution. Finally, we suggest the universal use of the Belnap, Büdel & Lange definition, with minor modifications: Biological soil crusts (biocrusts) result from an intimate association between soil particles and differing proportions of photoautotrophic (e.g. cyanobacteria, algae, lichens, bryophytes) and heterotrophic (e.g. bacteria, fungi, archaea) organisms, which live within, or immediately on top of, the uppermost millimetres of soil. Soil particles are aggregated through the presence and activity of these often extremotolerant biota that desiccate regularly, and the resultant living crust covers the surface of the ground as a coherent layer. With this detailed definition of biocrusts, illustrating their ecological functions and widespread distribution, we hope to stimulate interest in biocrust research and inform various stakeholders (e.g. land managers, land users) on their overall importance to ecosystem and Earth system functioning.

Abstract: A collation of the available lichen records for churches, graveyards and burial grounds in England from 1650 to January 2017, for purposes of conservation, future monitoring and research. Habitat and substrate information is included where available.

Abstract: Lichens: Records administered by the KMBRC.

Abstract: Lists of Lichens recorded during the Botanical Society of Edinburgh excursion to Knoydart.

Abstract: This survey was commissioned by the John Muir Trust to study the lichen communities of the Ben Nevis plateau and any threats posed to these communities. Field work was carried out over a 4 day period in September 2006. The plateau is a vast boulder-field with pebble, cobble, and boulder size scree and occasional outcrops. The rock is of two lava types: Trachyte and Dacite.

Abstract: Lichens are the symbiotic outcomes of open, interspecies relationships, central to which are a fungus and a phototroph, typically an alga and/or cyanobacterium. The evolutionary processes that led to the global success of lichens are poorly understood. In this review, we explore the goods and services exchange between fungus and phototroph and how this propelled the success of both symbiont and symbiosis. Lichen fungal symbionts count among the only filamentous fungi that expose most of their mycelium to an aerial environment. Phototrophs export carbohydrates to the fungus, which converts them to specific polyols. Experimental evidence suggests that polyols are not only growth and respiratory substrates but also play a role in anhydrobiosis, the capacity to survive desiccation. We propose that this dual functionality is pivotal to the evolution of fungal symbionts, enabling persistence in environments otherwise hostile to fungi while simultaneously imposing costs on growth. Phototrophs, in turn, benefit from fungal protection from herbivory and light stress, while appearing to exert leverage over fungal sex and morphogenesis. Combined with the recently recognized habit of symbionts to occur in multiple symbioses, this creates the conditions for a multiplayer marketplace of rewards and penalties that could drive symbiont selection and lichen diversification.

Abstract: Observations opportunistes Flore, Fonge et Bryophytes de l'ONCFS en Midi-Pyrénées

Abstract: DREAL_Lichens / Les données ont été acquises par le Conservatoire botanique national du Massif-Central.

Abstract: Lichens are among the most widely distributed plants on earth and have the longest growth cycle. Usnic acid is an abundant characteristic secondary metabolite of lichens and the earliest lichen compound used commercially. It has diverse pharmacological activities, such as anti-inflammatory, antibacterial, antiviral, anticancer, antioxidant, and photoprotective effects, and promotes wound healing. It is widely used in dietary supplements, daily chemical products (fodder, dyes, food, perfumery, and cosmetics), and medicine. However, some studies have found that usnic acid can cause allergic dermatitis and drug-induced liver injury. In this paper, the bioactivity, toxicity, in vivo and in vitro metabolism, and pharmacokinetics of usnic acid were summarized. The aims were to develop and utilize usnic acid and provide reference for its future research.

Abstract: Partner flexibility is increasingly recognized as integral to successful mutualistic symbioses. Fungi are some of the most diverse, impactful, and widespread mutualistic symbionts. Growing evidence from lichen genomics, biochemistry, evolution, and ecology are challenging long-held perspectives on these key groups of mutualists. We draw on this new research to present a framework for reconceptualizing lichens and propose lichen symbioses as ideal model systems. Several decades of research across disciplines have overturned historical perspectives of symbioses dominated by binary characterizations of highly specific species–species interactions. This paradigm shift has unlocked the previously underappreciated and overlooked dynamism of fungal mutualisms such as mycorrhizae. Lichens are another example of important fungal mutualisms where reconceptualization is urgently needed to realize their potential as model systems. This reconceptualization requires both an objective synthesis of new data and envisioning a revised integrative approach that unifies the spectrum of ecology and evolution. We propose a ten-theme framework that if pursued would propel lichens to the vanguard of symbiotic theory. Several decades of research across disciplines have overturned historical perspectives of symbioses dominated by binary characterizations of highly specific species–species interactions. This paradigm shift has unlocked the previously underappreciated and overlooked dynamism of fungal mutualisms such as mycorrhizae. Lichens are another example of important fungal mutualisms where reconceptualization is urgently needed to realize their potential as model systems. This reconceptualization requires both an objective synthesis of new data and envisioning a revised integrative approach that unifies the spectrum of ecology and evolution. We propose a ten-theme framework that if pursued would propel lichens to the vanguard of symbiotic theory. a series of chemical reactions in living organisms that are catalyzed by enzymes. interactions between two or more living organisms. a symbiotic relationship in which one partner benefits while the other is neither harmed nor benefited. a character that arises independently in evolutionary unrelated organisms. the total breadth of multidimensional ecological conditions in which a species can survive. extraordinarily complex communities of microbial symbionts from a minimum of three evolutionarily distantly related phyla representing at least two kingdoms and that repeatedly form a phenotypically consistent, recognizable, mutually beneficial symbiosis. Taxonomically classified by the primary fungus and defined by a quintessential mutualistic relationship between that fungus and one or more photosynthesizing partners. a symbiotic relationship in which all partners benefit. soil-dwelling fungi that form mutualistic symbiotic relationships with plants wherein hyphae connect directly to the roots. when an organism remains at equilibrium with the moisture content of the surrounding environment. substances that are generated through the processes that maintain the basic functions in cells and organisms. substances produced by organisms that are not required for primary metabolism, vary between species, and with concentrations that can vary across tissues or growth stages. the ability of one symbiont to associate with a diversity of other symbiont species or genotypes. the degree of taxonomic breadth and genetic diversity among partners in a symbiosis (e.g., one-to-one versus one-to-many). intimate, sustained biotic interactions with variable degrees of benefits for the partners involved. the means by which an organism acquires essential nutrients.

Abstract: Historically the study of diet caribou and reindeer (Rangifer tarandus (Gmelin, 1788)) has been specific to herds and few comprehensive circumpolar analyses of Rangifer diet exist. As a result, the importance of certain diet items may play an outsized role in the caribou diet zeitgeist, e.g., lichen. It is incumbent to challenge this notion and test the relevant importance of various diet items within the context of prevailing hypotheses. We provide a systematic overview of 30 caribou studies reporting caribou diet and test biologically relevant hypotheses about spatial and temporal dietary variation. Our results indicate that in the winter caribou primarily consume lichen, but in warmer seasons, and primary productivity is lower, caribou primarily consume graminoids and other vascular plants. In more productive environments, where caribou have more competitors and predators, consumption of lichen increased. Overall, our description of caribou diet reveals that caribou diet is highly variable, but in circumstances where they can consume vascular plants, they will. As climate change affects Boreal and Arctic ecosystems, the type and volume of food consumed by caribou has become an increasingly important focus for conservation and management of caribou.

Abstract: Abstract Lichen symbioses are thought to be stabilized by the transfer of fixed carbon from a photosynthesizing symbiont to a fungus. In other fungal symbioses, carbohydrate subsidies correlate with reductions in plant cell wall-degrading enzymes, but whether this is true of lichen fungal symbionts (LFSs) is unknown. Here, we predict genes encoding carbohydrate-active enzymes (CAZymes) and sugar transporters in 46 genomes from the Lecanoromycetes , the largest extant clade of LFSs. All LFSs possess a robust CAZyme arsenal including enzymes acting on cellulose and hemicellulose, confirmed by experimental assays. However, the number of genes and predicted functions of CAZymes vary widely, with some fungal symbionts possessing arsenals on par with well-known saprotrophic fungi. These results suggest that stable fungal association with a phototroph does not in itself result in fungal CAZyme loss, and lends support to long-standing hypotheses that some lichens may augment fixed CO 2 with carbon from external sources.

Abstract: The Indian Himalayan Region harbor about half of the flowering plant species recorded in India, of which nearly 30% species are endemic. The state of Uttarakhand, also known as the ‘herbal state of India,’ harbors more than 5000 species of vascular plants, of which one-third species have medicinal uses. Thus, considering the immense floral, ecological, and ethno-botanical values, the current communication aims to conduct an extensive review of scientific research on such aspects in this Himalayan state, in the absence of any such previous attempt. Based on an extensive review of 276 studies in the form of scientific peer-reviewed literature on floristics, medicinal and aromatic plants, ethno-botany, and threatened species, it is revealed that among various plant groups, vascular plants including angiosperms, gymnosperms and pteridophytes are the most studied group. Angiosperms alone accounts to 15% of the studies followed by pteridophytes and gymnosperms (10% each), whereas, the lower plants are distinctly understudied with lichens (8%) and bryophytes (6%). Interestingly, the alpine, sub-alpine, and temperate regions are explored in terms of floristic studies as compared to lower elevations such as Upper Gangetic Plains and adjacent Siwalik and Sub-Himalayan tracts in the state. The present review highlights that the remote cold-arid regions along the northern frontiers such as Nilang, Niti, Girthi, Mana, Johar, Darma, and Byans valleys, to name a few are under explored or unexplored in terms of current levels of pressure or patterns of plant diversity. Further, knowledge on the available growing stock of threatened vis-à-vis high-value medicinal plants, information on agro-techniques of key threatened species-specific to their landscape, information on the quantity of raw material traded that eventually leads to decline in its natural population, regeneration, and survival are the matter of grave concern. Subsequently, addressing depleting ethno-botanical knowledge, studies pertaining to the lower plants, control over exploitation, illegal or pre-mature harvesting of economically valued threatened and medicinal species is the need of the hour.

Abstract: Free radicals play a critical role in the chemical processes that occur in all cells. Pharmaceutical companies manufacture a variety of synthetically prepared antioxidants, but it is known that many of these can be carcinogenic. As a result, efforts are being made to find natural antioxidants that do not have these side effects. Lichens may be suitable candidates because they contain secondary metabolites with proven antioxidant properties. This could be explained by the presence of compounds with phenolic groups in lichens. The radical scavenging reaction is a chemical reaction governed by stoichiometry, and our aim is to determine the efficacy of these reactions. The aim of this study is to compare metabolite activity based on the same amount of substance involved in radical scavenging, calculated in micromoles rather than weight concentration. This provides an accurate way of comparing radical scavenging activity. We tested superoxide anion scavenging activity and free radical scavenging activity of isolated lichen secondary metabolites and their mixtures in different ratios. The following compounds were isolated and tested for antioxidant activity: gyrophoric acid (Umbilicaria hirsuta), evernic acid (Evernia prunastri), physodic acid, 3-hydroxyphysodic acid, physodalic acid and atranorin (Hypogymnia physodes), and usnic acid (as a synthetic compound). Of all the tested compounds, 3-hydroxyphysodic acid, as well as mixtures containing this metabolite, showed the strongest scavenging activity. The results also demonstrated that calculation by amount of substance leads to a new consideration of antioxidant activity.

Abstract: This dataset contains the digitized treatments in Plazi based on the original journal article Habib, Kamran, Zulfiqar, Rizwana, Khalid, Abdul Nasir (2022): Lecaimmeria pakistanica, a new lichen from Azad Jammu and Kashmir, Pakistan. European Journal of Taxonomy 834: 94-101, DOI: 10.5852/ejt.2022.834.1901, URL: http://dx.doi.org/10.5852/ejt.2022.834.1901

Abstract: We assess the identification accuracy of ‘research grade’ observations of lichens posted on the online platform iNaturalist. Our results show that these observations are frequently misidentified or lack the necessary chemical and (or) microscopic information for accurate identification. Lichens are a taxonomically difficult group, but they are ubiquitous and eye-catching and are regularly the subject of observations posted on iNaturalist. Therefore, we provide best practice recommendations for posting lichen observations and commenting on observations. Data from iNaturalist are a valuable tool for understanding and managing biodiversity, particularly at this crucial time when large scale biodiversity decline is occurring globally. However, the data must be accurate for them to effectively support biodiversity conservation efforts. Our recommendations are also applicable to other taxonomically difficult taxa.

Abstract: 2020_02_28_Leprince_lichens

Abstract: Biodiversity is a key criterion in nature protection and often indicates habitats and localities rich in endangered species. Our research, using 48 one-man one-day field trips, located an exceptional lichen diversity hotspot and refugium for rare species, the Týřov National Nature Reserve (Czech Republic, central Bohemia). Within its 410 hectares, we detected 787 species of lichens and related taxa (675 lichens, 35 semilichens, 58 lichenicolous fungi and 19 bark microfungi). This is more species of these organisms than has ever been recorded from such a small area, up to 10 km2, anywhere in Europe (and probably anywhere in the world). The species richness is positively correlated with the habitat heterogeneity within Týřov, which is very far from uniform. In most of the reserve, the species richness is fairly typical for the broader region, and only three sites, with an overall area of a mere 80 hectares, have distinctly higher species richnesses. The most species-rich site, with 502 species, is only about 25 hectares and is distinctly more diverse in habitats than other sites. The enormous importance of Týřov for biodiversity protection is emphasized by the nine species described as new to science: Acarospora fissa, Bacidia hyalina, Buellia microcarpa, Micarea substipitata, Microcalicium minutum, Rufoplaca griseomarginata, Verrucaria substerilis, V. tenuispora and V. teyrzowensis. Three species are new to Europe, 55 to the Czech Republic and 191 species are included in the national Red-list.

Abstract: GALTIER_Lichen_Mezenc / Les données ont été acquises par le Conservatoire botanique national du Massif-Central.

Abstract: Lichens and mosses play important functional roles in all terrestrial ecosystems, particularly in tundra and drylands. As with all taxa, to maintain their current niche in a changing climate, lichens and mosses will have to migrate. However, there are no published estimates of future habitat suitability or necessary rates of migration for members of these groups at the global scale.

Abstract: 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 analyze populations of two lichen symbioses, Umbilicaria pustulata and U. hispanica, along an elevational gradient spanning 2100 altitudinal meters 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 11-13°C average annual temperature (here: 800-1200m a.s.l.), and at 7-9°C average annual temperature (here: 1500-1800m a.s.l.). The two observed zones mark a clustering of distribution limits and community shifts. The three ensuing altitudinal classes, i.e. 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, e.g. vascular plants.

Abstract: Fungal–algal relationships—both across evolutionary and ecological scales—are finely modulated by the presence of the symbionts in the environments and by the degree of selectivity and specificity that either symbiont develop reciprocally. In lichens, the green algal genus Trebouxia Puymaly is one of the most frequently recovered chlorobionts. Trebouxia species-level lineages have been recognized on the basis of their morphological and phylogenetic diversity, while their ecological preferences and distribution are still only partially unknown. We selected two cosmopolitan species complexes of lichen-forming fungi as reference models, i.e., Rhizoplaca melanophthalma and Tephromela atra, to investigate the diversity of their associated Trebouxia spp. in montane habitats across their distributional range worldwide. The greatest diversity of Trebouxia species-level lineages was recovered in the altitudinal range 1,000–2,500 m a.s.l. A total of 10 distinct Trebouxia species-level lineages were found to associate with either mycobiont, for which new photobionts are reported. One previously unrecognized Trebouxia species-level lineage was identified and is here provisionally named Trebouxia “A52.” Analyses of cell morphology and ultrastructure were performed on axenically isolated strains to fully characterize the new Trebouxia “A52” and three other previously recognized lineages, i.e., Trebouxia “A02,” T. vagua “A04,” and T. vagua “A10,” which were successfully isolated in culture during this study. The species-level diversity of Trebouxia associating with the two lichen-forming fungi in extreme habitats helps elucidate the evolutionary pathways that this lichen photobiont genus traversed to occupy varied climatic and vegetative regimes.

Abstract: Lichens are well-known examples of complex symbiotic associations between organisms from different Kingdoms. Microfungi in particular, establish diverse associations with the hosting lichen thallus, as species-specific parasites or transient co-inhabitants. The whole community of lichen-associated fungi constitute the 'lichen mycobiome' comprising both ascomycetes and basidiomycetes, including filamentous and yeast taxa. Metabarcoding results and microscopy analyses show that in some thalli, basidiomycetes are frequent lichen-associated fungi but still only a few species could be axenically isolated and morphologically characterized. Within a broad project aiming at characterizing the mycobiome diversity by culture-dependent and independent approaches in two lichen species selected as reference models - Rhizoplaca melanophthalma and Tephromela atra, we succeed in isolating and culturing 76 new strains of basidiomycetous yeasts. The lichen thalli were collected in different mountain regions worldwide and at relatively high elevation. The yeast strains were isolated on different growth media and were studied for their morphological and genetic diversity. Nuclear internal transcribed spacer (ITS) and ribosomal large subunit (LSU) sequence analyses identified them to belong to ten families within the orders Agaricostilbomycetes, Cystobasidiomycetes, Microbotryomycetes, Tremellomycetes and Ustilaginomycetes. The yeasts here detected showed patterns of host-preference in a few cases and they are potentially related to the ecological conditions.