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Deforestation is the most important cause of biodiversity loss in tropical ecosystems. Epiphytic species, lichens and bryophytes, are very sensitive to environmental changes, including those produced by conversion of primary forests into secondary vegetation. However, little is known about the differences between different secondary forests and plantations regarding the epiphytic biota. We compared epiphytic communities among different secondary forests and non-native plantations in southern Ecuador. Four forest types were considered: non-native Pinus patula plantations, monospecific secondary forests of Alnus acuminata, monospecific secondary forests of Andesanthus lepidotus and mixed secondary forests. Within each forest type, two stands were surveyed, establishing a total of 80 plots and analyzing four trees per plot. We estimated lichen and bryophyte cover in four inventories per tree and calculated and compared different metrics for taxonomic and functional diversity, as well as community composition. The results revealed forest type as the major predictor for the species and functional traits richness, and for diversity and composition. In total, 422 taxa were identified (312 lichens and 110 bryophytes), with mixed secondary forests having the richest communities (194 species) and non-native plantations having the lowest richness (105 species). Bryophyte richness was highest in A. lepidotus forests. Taxonomic and functional diversity, and species composition differed greatly among forest types and followed a different pattern depending on the organism considered. Lichens were the most sensitive indicators of environmental conditions associated with different tropical forest types.

The present paper reports the first record of Diplotomma cedricola (Werner) Etayo in the eastern Mediterranean (Creta Island, Greece), being the nearest record from Corsica (France). This lichen species was found near Iérapreta on decorticated Cupressus sempervirens L. and Pinus brutia Ten. trees. This finding constitutes a great expansion of the distribution range of this species.

RESUMEN Los trópicos albergan la mayor biodiversidad del planeta, pero todavía son zonas inexploradas. Entre estas áreas remotas se encuentran los Tepuyes del Valle de Nangaritza, en la provincia de Zamora Chin-chipe, al sureste de Ecuador. Constituyen sistemas montañosos aislados de gran importancia biológica y con altos niveles de endemicidad. Debido a estas características, el objetivo principal del estudio es elaborar el primer catálogo de líquenes epifitos de varios Tepuyes del Valle de Nangaritza. Como resultado de dos expediciones realizadas en los Tepuyes, entre 900 y 2000 m de altitud, se recolectaron aproximadamente 1.000 muestras de líquenes en diferentes hábitats: bosque denso piemontano, bosque denso montano bajo, bosque chaparro y páramo arbustivo atípico. Se identificaron 174 especies, pertenecientes a 57 géneros y 26 familias. De ellas, trece especies son nuevos registros para Sudamé-rica, 64 para Ecuador y 132 para la provincia de Zamora Chinchipe. Se encontraron nuevos quimiótipos para especies de la familia Cladoniaceae. La forma de crecimiento crustácea fue dominante, con alrededor del 40 % de la riqueza total, siendo Graphidaceae la familia con mayor riqueza (27 especies). Predominaron las especies de líquenes con alga verde como fotobionte, presentando Trenthepholia un gran número de especies (66 especies). Este catálogo es una primera aproximación al conocimiento de la diversidad de líquenes de los Tepuyes del Valle de Nangaritza, donde el alto número de nuevos registros indican la falta de conocimiento de la diversidad asociada a estos bosques tropicales. ABSTRACT Tropics harbour the greatest biodiversity in the planet but are still largely unknown. Among these remote areas, there are the Tepuyes of Nangaritza Valley, in the Zamora Chinchipe province, southeastern Ecuador. They constitute isolated mountainous systems with great biological importance and high levels of endemicity. Therefore, the main objective of this study was the elaboration of the first catalogue of epiphytic lichens from several Tepuyes in the Nangaritza Valley. Two expeditions were carried out in two Tepuyes, between 900 and 2000 m of altitude, approximately 1,000 samples of lichens where collected at different habitats: piemontane wet forest, lower montane wet forest, dwarf forest, and paramillo. We identified 174 lichen species, belonging to 57 genera and 26 families. We found thirteen new records for South America, 64 for Ecuador, and 132 for the Zamora Chinchipe province. New chemotypes for species belonging to the Cladoniaceae family were found. Lichens with a crustose growth-form were the most abundant with around 40 % of the total richness, being Graphidaceae the richest family (27 species). Lichen species with green algae as photobiont were dominant, and especially those with Trenthepholia (66 species). This catalogue is a first approximation to the knowledge of the diversity of lichens from the Tepuyes of the Nangaritza Valley, and the high number of new records indicates a lack of knowledge of the biodiversity from these tropical forests.

Tropical dry forests have been recognized as one of the most threatened ecosystems in the world due to deforestation. These ecosystems harbour a high endemicity of epiphytes, which play a major role in the functioning of the forests. Lichens constitute an important fraction of the epiphytes. These poikilohydric organisms respond drastically to disturbance, which is strongly linked to humidity and light availability. We hypothesized that richness and species composition of lichens would be related to differences in forest structure (e.g., canopy openness) promoted by deforestation, and by host tree characteristics, due to the fact that dry forests generally have poor microclimatic stratification and low diversity of tree species. In this study, we assessed the richness and composition of epiphytic lichens on the trunks of 513 trees in undisturbed and disturbed dry forests of southern Ecuador. Both lichen composition and richness were highly correlated with tree species and host tree traits such as bark structure and tree diameter. Additionally, epiphytic lichen diversity was related to canopy cover and tree richness at different disturbance levels. We conclude that epiphytic lichen communities in seasonal dry tropical forests of Ecuador are mainly limited by host tree traits and tree species. Loss of epiphytic lichen species in the studied forests is particularly due to loss of host trees such as Cochlospermum vitifolium and Eriotheca ruizii, that maintain high species richness.

Assessing the response of biological communities to contrasting environmental conditions is crucial to predict the effects of global change drivers. The influence of multiple environmental factors may differ depending on the diversity facet considered, which emphasizes the need to simultaneously evaluate the functional (FD), phylogenetic (PD) and taxonomic (TD) diversity. To examine how these facets of biodiversity respond to environmental changes, we studied lichen epiphytic communities across 47 beech forest fragments from two biogeographic regions. We applied structural equation modelling to relate habitat fragmentation, climate and habitat quality with FD, PD and TD. We compared the community response to contrasting climatic conditions by analysing independently Atlantic and Mediterranean communities. We found different major drivers of biodiversity patterns across biogeographic regions. Habitat fragmentation performed the highest effect on lichen communities, with a reduction of FD, PD and TD at both regions. However, the influence of climate was stronger in the Atlantic region than in the Mediterranean region, where the effect of habitat quality was superior. The effect of the environmental predictors over PD and TD was both direct and indirect through the different components of FD, and their intensity and sign differed across regions. Changes in PD were not related to changes in TD. Synthesis. Our results evidenced that the major environmental drivers affecting epiphytic communities were geographically structured. These drivers modified the diversity of the epiphytic community directly but also indirectly through changes in FD, which emerged as a causal but not unique determinant of PD and TD. Our findings also showed the difficulty for inferring TD through PD. These results emphasize the essential role of FD predicting part of the response of lichen communities to global change drivers but also highlight the importance of considering multiple biodiversity facets to understand the effects of environmental change on community structure.

Se presentan los resultados del estudio sobre la diversidad de líquenes terrícolas en Montes de Toledo. Se han identificado 103 especies, 14 se citan por primera vez en Castilla-La Mancha y otras 32 son novedad para Montes de Toledo. Las zonas con mayor riqueza son los taludes de pistas forestales del interior de melojares o los cercanos a los cauces de ríos. Destacamos algunas especies más caraterísticas del norte peninsular, que en la zona de estudio se refugian en los taludes más frescos y húmedos (Cladonia ciliata, C. gracilis, C. scabriuscula, C. uncialis, Inoderma epigaeum, Lepraria rigidula, Peltigera venosa, Psoroma hypnorum, Trapeliopsis pseudogranulosa). En zonas más expuestas destacamos algunas especies mediterráneas muy escasas en el territorio peninsular (Cladonia dimorpha, Leptogium terrenum, Toninia toepfferi, Trapeliopsis gymnidiata, T. wallrothii). En conclusión, bajo condiciones de clima mediterráneo, los taludes de caminos y pistas forestales constituyen hábitats esenciales para la instalación de especies terrícolas

The Amazonian rain forests of Yasuni National Park, Ecuador (YNP), count among the world's forests regions with highest biodiversity, but are strongly threatened by deforestation. Cryptogams (bryophytes and lichens) are common and characteristic organisms in these forests, are sensitive to environmental changes, and are considered effective ecological indicators. The objective of this study was to explore the response of epiphytic cryptogams to forest succession in the Amazonian forests of YNP. We hypothesized that alteration of structural and micro-environmental characteristics of the forest, including reduction of canopy cover and lowering of tree species richness, lead to a reduction of species richness and changes in species composition of epiphytic cryptogams. We assessed species richness and composition of cryptogams on the bases of 442 trees in three stage of forest succession (early, intermediate, late), using generalized linear mixed models, multivariate analysis, beta diversity components and Mantel test. We registered 146 species of cryptogams, including 50 of lichens and 96 of bryophytes (39 mosses, 57 liverworts). Diversity of epiphytic cryptogams was highest in late succession forest, and lowest in early succession forest. Major changes in species richness and composition correlated with changes in canopy openness relative to the shift from early to late stages of forest succession. The results demonstrate for the first time the importance of tree species richness for cryptogamic epiphyte richness in Amazonian rain forests. Maintenance of high tree species diversity and structural heterogeneity in late succession forests can considerably contribute to the conservation of the cryptogamic epiphytes of Amazonian rain forests.

Characterizing functional trait variation and covariation, and its drivers, is critical to understand the response of species to changing environmental conditions. Evolutionary and environmental factors determine how traits vary among and within species at multiple scales. However, disentangling their relative contribution is challenging and a comprehensive trait–environment framework addressing such questions is missing in lichens. We investigated the variation in nine traits related to photosynthetic performance, water use and nutrient acquisition applying phylogenetic comparative analyses in lichen epiphytic communities on beech across Europe. These poikilohydric organisms offer a valuable model owing to their inherent limitations to buffer contrasting environmental conditions. Photobiont type and growth form captured differences in certain physiological traits whose variation was largely determined by evolutionary processes (i.e. phylogenetic history), although the intraspecific component was non-negligible. Seasonal temperature fluctuations also had an impact on trait variation, while nitrogen content depended on photobiont type rather than nitrogen deposition. The inconsistency of trait covariation among and within species prevented establishing major resource use strategies in lichens. However, we did identify a general pattern related to the water-use strategy. Thus, to robustly unveil lichen responses under different climatic scenarios, it is necessary to incorporate both among and within-species trait variation and covariation.

Assessing the ecological impacts of environmental change on biological communities requires knowledge of the factors driving the spatial patterns of the three diversity facets along extensive environmental gradients. We quantified the taxonomic (TD), functional (FD), and phylogenetic diversity (PD) of lichen epiphytic communities in 23 beech forests along Europe to examine their response to environmental variation (climate, habitat quality, spatial predictors) at a continental geographic scale. We selected six traits related to the climatic conditions in forest ecosystems, the water-use strategy and the nutrient uptake, and we built a phylogenetic tree based on four molecular markers. FD and climate determined TD and PD, with spatial variables also affecting PD. The three diversity facets were primarily shaped by distinct critical predictors, with the temperature diurnal range affecting FD and PD, and precipitation of the wettest month determining TD. Our results emphasize the value of FD for explaining part of TD and PD variation in lichen communities at a broad geographic scale, while highlighting that these diversity facets provide complementary information about the communities&rsquo, response under changing environmental conditions. Furthermore, traits such as growth form, photobiont type, and reproductive strategy mediated the response of lichen communities to abiotic factors emerging as useful indicators of macroclimatic variations.

The anthropocene is characterised by global landscape modification, and the structure of remnant habitats can explain different patterns of species richness. The most pervasive processes of degradation include habitat loss and fragmentation. However, a recovery of modified landscape is occurring in some areas. The main goal is to know how lichen and bryophyte epiphytic richness growing on Mediterranean forests is influenced not only by fragments characteristics but also by the structure of the landscape. We introduce a temporal dimension in order to evaluate if the historical landscape structure is relevant for current epiphytic communities. 40 well-preserved forest fragments were selected in a landscape with a large habitat loss over decades, but with a recovery of forest surface in the last 55 years. The most relevant fragment and landscape-scale attributes were considered. Some of the variables were measured in three different years to incorporate a temporal framework. The results showed that variables at fragment scale had a higher influence, whereas variables at the landscape scale were irrelevant. Among all the historical variables analyzed, only the shift in forest fragment size had influence on species richness. Mediterranean forests had suffered fragmentation along centuries. Their epiphytic communities also suffer the hard conditions of Mediterranean climate. Our results indicate that Mediterranean epiphytic communities may be in a threshold since it they will never be similar to those communities existing previous fragmentation process even a recovery habitat occur or, they may require more time to response to this habitat recovery.

Epiphytic lichens are good ecological indicators of climatic and environmental changes. The physiology of lichens is related with their morphology and anatomy (traits) and thus the response to changes in the environment could be related with these traits. In this study we evaluate lichen functional traits to understand the mechanisms of community assembly in response to deforestation of tropical montane forests in Ecuador. Based on this, we propose and indicator value as a complement to evaluate the disturbance level of forests. Finally, we evaluate the use of selected functional traits to infer total species richness and diversity of tropical montane forests. We assessed nine different traits related with photobiont type, growth form, reproductive strategy and chemistry of epiphytic lichens on the trunk bases of 240 trees in three types of forests according to a disturbance gradient (primary forests and secondary vegetation). Most functional traits of the lichen communities were related to structural changes (i.e canopy cover and tree diameter) along the forest disturbance gradient. Several functional groups of lichens as cyanolichens, and those with a gelatinose, filamentose and squamulose growth forms and species without secondary compounds were more abundant in primary forests. On the other hand, fruticose, foliose species with narrow lobes, and with lirellae were most abundant in disturbed forest. Growth forms are useful to infer total lichen richness and diversity in montane tropical forests. Based on these results we recommend the use of lichen functional traits as a tool and a complement for conservation studies and forest management.

Ecological studies of five paramos in Azuay and Loja provinces recorded one lichen species new to South America (Bryoria nitidula), five new to Ecuador (Cladonia halei, C. melanopoda, C. merochlorophaea, C. subreticulata, Diploschistes diacapsis), two new to mainland Ecuador (Cladonia grayi, C. pyxidata), and 20 new provincial records. Brief morphological descriptions, with remarks on distribution and ecology, are provided.

Adopting an integrative approach that explicitly includes the different facets of biodiversity is crucial to assess the response of biological communities to changing environments. The identification of the optimal climatic conditions where communities maximize their functional, phylogenetic and taxonomic diversity is useful to compare whether the optima of the different facets of biodiversity match. Using a wide climatic gradient across Europe, we quantified the functional, phylogenetic and taxonomic diversity of epiphytic macrolichen communities, which are valuable early-warning ecological indicators. We ordinated 22 environmental variables and simultaneously illustrated non-parametric regressions of the diversity metrics against the climatic space using the 'hilltop plot' method to detect the climatic conditions in which the different diversity facets peaked and to compare the match between them. Functional diversity predicted at least part of the peaks of phylogenetic and taxonomic diversity, but phylogenetic and taxonomic hotspots did not overlap. Epiphytic macrolichen communities maximized their functional and phylogenetic diversity in the southernmost forests, with the Mediterranean region appearing as a biodiversity hotspot. Regarding the studied traits, photobiont type and growth form showed clearly defined optima while the quantitative physiological traits and families' optima did not show this pattern in response to climate. The different facets of biodiversity were not surrogates of each other highlighting the need for an integrative approach to assess the effect of environmental changes on communities and to establish conservation priorities. As functional traits mediated the response of lichen communities to climate, preserving high functional diversity might indirectly preserve high phylogenetic and taxonomic diversity. Relevant ecological indicators useful to develop rapid assessment methods to evaluate the effects of climatic changes include the photobiont type and growth form. The lack of relation between quantitative traits and climate call for further research to unveil their role as ecological indicators of small-scale variables or as effect traits.

Background and AimsIn order to re-establish lichen symbiosis, fungal spores must first germinate and then associate with a compatible photobiont. To detect possible establishment limitations in a sexually reproducing cyanolichen species, we studied ascospore germination, photobiont growth and photobiont association patterns in Pectenia plumbea.MethodsGermination tests were made with ascospores from 500 apothecia under different treatments, and photobiont growth was analysed in 192 isolates obtained from 24 thalli. We determined the genotype identity [tRNALeu (UAA) intron] of the Nostoc cyanobionts from 30 P. plumbea thalli from one population. We also sequenced cyanobionts of 41 specimens of other cyanolichen species and 58 Nostoc free-living colonies cultured from the bark substrate.Key ResultsNot a single fungal ascospore germinated and none of the photobiont isolates produced motile hormogonia. Genetic analyses revealed that P. plumbea shares Nostoc genotypes with two other cyanolichen species of the same habitat, but these photobionts were hardly present in the bark substrate.ConclusionsDue to the inability of both symbionts to thrive independently, the establishment of P. plumbea seems to depend on Dendriscocaulon umhausense, the only cyanolichen species in the same habitat that reproduces asexually and acts as a source of appropriate cyanobionts. This provides support to the hypothesis about facilitation among lichens.

Traditional approaches in trait‐based community ecology typically expect that trait filtering across broad environmental gradients is largely due to replacement of species, rather than intraspecific trait adjustments. Recently, the role of intraspecific trait variability has been largely highlighted as an important contributor mediating the ability of communities to persist under changing conditions and determining the community‐level trait variation, particularly across limited environmental gradients. Unfortunately, few studies quantify the relative importance of species turnover versus intraspecific variability mediating the response of communities different from vascular plants. Here, we studied the functional changes in epiphytic lichen communities within 23 beech forests across large latitudinal (ca. 3,000 km) and environmental gradients in Europe to quantify the relative contribution of species turnover and intraspecific variability and the role of climate controlling community‐level trait changes. For 58 lichen species, we focused on a set of 10 quantitative functional traits potentially affected by climatic conditions and related to photosynthetic performance (n = 1,184 thalli), water use strategy (n = 1,018 thalli), and nutrient uptake (n = 1,179 thalli). Our results showed that intraspecific trait variability explained most of the functional changes in lichen communities in response to the latitudinal gradient. Further, such functional changes were determined by the covariation between intraspecific trait variability and species turnover, which varied in sign depending on the trait considered. Finally, different climatic predictors explained functional variation due to both intraspecific trait variability and species turnover. We propose that lichen communities cope with contrasting climatic conditions by adjusting the functional trait values of the most abundant species within the communities rather than by the replacement of the species. Consequently, intraspecific variability should be explicitly incorporated to understand the effect of environmental changes on lichen communities, even over large environmental variations, better. Our results challenge the universality of the hypothesis that species turnover chiefly drives functional trait changes across large environmental gradients and call for a wider test of such important assumptions in trait ecology in different organism types and ecosystems., Ministerio de Economía y Competitividad. Grant Numbers: CGL2013‐47010‐P, CGL2016‐80562‐P, EEBB‐I‐17‐12573 REMEDINAL TE-CM. Grant Number: S2018/ EMT-4338

Mediterranean forests have been fragmented intensively over time, thereby yielding small and isolated forest remnants. They host a rich variety of epiphytes, which may be affected by landscape structure. Previous studies have analyzed the influence of habitat quality on these epiphytic communities, but there is little knowledge of the effects of other fragment features. We evaluated the impacts of forest loss and fragmentation on epiphytic communities (lichens and bryophytes) at plot and fragment scales after controlling the variation in forest structure and management. We considered 40 fragments of dense oak forests in a human-modified landscape. We quantified their spatial attributes (size and shape), the quality of the surrounding matrix and the forest stand structure. We modeled community traits, and the presence and abundance of species at fragment and plot scales. Fragment size, shape, and the quality of the surrounding matrix were key factors that affected epiphytic richness and diversity. Larger and more regularly shaped fragments hosted the richest and most diverse communities, possibly offering a larger core area and thus favoring the entry of typical forest species. A high-contrast matrix was only favorable in small fragments, probably allowing the arrival of propagules. The species-level response was highly variable. Landscape structure provides powerful explanations of the richness and diversity losses among epiphytes. Forest management should ensure the retention of the largest possible continuous forests. The management strategy of the matrix will depend on the conservation goal, since we observed different effects related with quality and fragment size.

The species richness of epiphytic lichens is continuously decreasing by degradation and loss of habitat. Considering that taxonomic identification of all species is time and resource consuming, rapid assessment methods to extrapolate the total number of species are needed for practical conservation. This paper describes an alternative method using the correlation between lichens growth forms and species richness. The study was conducted in 406 forest stands located in Central Spain, covering a wide range of mediterranean-climate ecosystem regions, management intensity levels, canopy cover conditions, and tree sizes. The presence/absence of epiphytic lichens was determined in 6090 trees, which were dominated by oak species ( Quercus ilex , Q. faginea , and Q. pyrenaica ). In all type of forests, the diversity of growth forms was positively correlated with the total epiphytic lichen richness. In all cases, species richness increased in non-managed forest stands with dense canopies. Thus, we propose the use of lichen growth forms as a helpful surrogate of species richness to detect potentially conservation priority areas in the Mediterranean region.

The current genetic diversity and structure of a species plays a marked role in the species' future response to environmental changes. Identification of the factors that might ensure the long-term viability of populations along its distribution area is therefore important for conserving biodiversity. In this work, infraspecific genetic diversity and structure of the threatened lichen Lobaria pulmonaria was investigated along a latitudinal gradient, spanning the Spanish latitudinal range of L. pulmonaria. Eighteen populations in Northern, Central, and Southern Spain were analysed using six specific fungal microsatellites of L. pulmonaria. Genetic diversity indices were calculated and compared among populations. Genetic differentiation was assessed using AMOVA and Bayesian methods. Additionally, a redundancy analysis was used to estimate the relative importance of environmental factors on the genetic variation among populations. Annual precipitation was the only factor affecting the genetic diversity probably through its influence on population and thallus size of L. pulmonaria, and significantly higher levels of genetic diversity were detected in southern populations. Isolation by distance was not significant, being environmental variables most important factors controlling genetic variation in L. pulmonaria populations.

The high richness of epiphytes in moist tropical montane forests is continuously decreasing due to deforestation and habitat loss. Lichens and bryophytes are important components of epiphyte diversity on trunk bases and play an important role in the water balance and nutrient cycling of tropical montane forests. As lichens and bryophytes are very sensitive to microclimatic changes, we hypothesized that their species richness and composition would change with forest alteration. We also expected their response patterns to be different given the capability of lichens to photosynthesize using water vapour. In this study, we assessed the richness and composition of epiphytes (lichens and bryophytes) on the trunk bases of 240 trees in primary and secondary forests of southern Ecuador. We found that diversity was higher in primary forests and lower in monospecific secondary forest stands. Total diversity was negatively affected by habitat loss and by the reduction of canopy cover for bryophytes. Shade epiphytes were replaced by sun epiphytes in open secondary forests. We conclude that lichen and bryophyte diversity of tropical montane forests are negatively affected by the removal of large trees and canopy disruption. The different species compositions of primary and secondary forests and the high number of species exclusive to primary forests indicate that secondary forests are of limited importance in compensating for the loss of non-vascular epiphyte species associated with primary forests.

Lobarina scrobiculata(better known asLobaria scrobiculata) is a widespread lichen, threatened and Red-Listed in various European countries. Microsatellite markers for the mycobiont ofL. scrobiculatawere developed in order to investigate its genetic diversity in the Iberian Peninsula and Europe and to design effective conservation strategies. A total of 7 polymorphic markers were isolated and characterized. These microsatellites were tested in natural populations found in the Iberian Peninsula. The number of observed alleles ranged from 3 to 8, and the Nei's unbiased gene diversity from 0·26 to 0·59. These microsatellite markers are the first to be developed forL. scrobiculataand they will be useful for population studies and for the assessment of the conservation status of this species.

Edge effect involves microclimatic variations (light, temperature and humidity) in the forest edge that become unsuitable for organisms adapted to forest interior conditions. We speculate that under similar edge types (shrubland matrix), the pattern in the response to forest edge might be different and more hostile for epiphytes in south- oriented edges. Because different matrix types have differ- ent effects on microclimate, we hypothesized that the magnitude of the edge effects will depend on the contrast between the physiognomy of the matrix and the forest fragment. The study was carried out in central Spain and consisted of a beech fragment surrounded by different types of vegetation matrices: pine plantation (south orientation), semi-deciduous oak forest (south orientation) and shrubland (north and south orientations). For each type of edge, we established ten transects perpendicular to the edge, running 100 m into the forest patch. Data were collected from three plots placed at 5, 50 and 100 m from the beginning of each transect. The results revealed that variations in the epiphytic composition mainly showed a replacement of forest interior species with generalist light-demanding species at forest edge. Shrubs-bordered edges showed the strongest influence on epiphytic composition, with high species dissimilarity between edge and forest interior, whereas the edge effects were mitigated when the patch was surrounded by other forests. Besides, in the case of shrub-bordered edge, the dissimilarity of species composition between edge interior was higher in the south than in the north-facing edge. We conclude that the magnitude of the edge effect on epiphytic communities is modulated by the physiognomy of the sur- rounding matrix and the orientation of the forest edge. In the case of a hard contrast matrix, at least 100 m of an edge buffer are required for the conservation of the species with high humidity requirements. Therefore, one of the main problems affecting the loss and even disappearance of sha- ded species is the decreasing of the amount of core condi- tions under the increasing forest fragmentation scenarios. This potentially exacerbates forest fragmentation effects linked to livestock use, due to the physiognomically dif- ferent surrounding matrix compared to forest patches.

Summary 1. Climate change is expected to cause several impacts at the global scale, and drylands will be amongst the most affected areas. Thus, investigating how these changes will affect the composition, structure and functioning of dryland ecosystems has become a priority. From an ecological indicator point of view, several works have shown that functional diversity is better than species richness to understand ecosystem functioning or response to environmental factors. However, most of these works focus on plants, while those of other organisms remain largely unknown. Lichens are amongst the ecosystem components more sensitive to climatic changes due to several physiological and ecological characteristics. Their poikilohydric nature (therefore highly dependent on the atmosphere for water supply) and their ubiquity on terrestrial ecosystems underlie their potential as indicators of climate. Nonetheless, works specifically aiming to identify lichen functional traits that respond to aridity remain poorly explored, particularly in drylands. 2. We proposed to identify lichen functional traits and respective functional groups responding to aridity in a Mediterranean drylands ecosystem. 3. Lichen diversity was sampled in open holm oak woodlands along an aridity gradient in SW Europe (Iberian Peninsula). Lichen functional traits that could be easily identified and related to water uptake were selected to be tested: type of photobiont, growth form and reproduction strategy. 4. Lichen species composition was related to the aridity gradient. The three traits chosen were related with the community’s response to aridity, but with contrasting responses in different functional groups. More specifically crustose and fruticose lichens, isidiate species and the ones with Trentepohlia as photobiont were related to the less arid part of the gradient. Foliose species and cyanolichens, on the contrary, were associated with the most arid areas. 5. Synthesis. We were able to identify lichen traits responding to aridity. Type of photobiont was particularly responsive, with Trentepohlia and cyanobacteria functional groups, responding clearly in contrasting ways to aridity in this drylands ecosystem. This work emphasizes functional diversity role on understanding and assessing the response to environmental factors, namely to climate. It also highlights the potential use of lichen functional groups as ecological indicators of climate change.

PREMISE OF THE STUDY High-quality information about threatened species is required to prevent current global biodiversity losses. Lichens are important components of forest biodiversity and help to maintain ecosystem functioning. The epiphytic cyanolichen Lobarina scrobiculata is red-listed in Europe and North America, but knowledge of its ecology and distribution in Southern Europe is scarce. METHODS We used a multispatial scale design to investigate the effects of macroclimate, forest structure, tree features, and microhabitat on the occurrence, abundance, spatial distribution, and performance of Lobarina scrobiculata in the Iberian Peninsula at plot and tree scales. Generalized linear models and mixed models were used for analysis. KEY RESULTS We recorded ca 14000 individuals of the threatened species Lobarina scrobiculata from 22 populations in the Iberian Peninsula. Our results suggest that L. scrobiculata thrives mainly in oak forests with highly variable annual precipitation levels. At the plot scale, the L. scrobiculata abundance increased with annual precipitation and tree density (habitat quantity). At the tree scale, our models highlighted the importance of tree size and bark roughness (habitat quality) as the main drivers of species occurrence and abundance. We detected a marked spatial pattern on tree trunks, i.e., L. scrobiculata occurred preferentially on north-facing surfaces and close to the ground where humidity is higher. CONCLUSIONS By integrating multiscale modeling, we analyzed a unique large dataset and these results are essential for understanding the ecology of this threatened cyanolichen. There is an urgent need to preserve the forests that this species currently inhabits as well as potential colonization sites.

[Question] In order to identify the factors and assembly rules which potentially shape natural lichen communities we asked whether these communities are phylogenetically and functionally structured along an environmental gradient in beech forests in the Iberian Peninsula. [Location] A climatic gradient in the Iberian Peninsula. [Methods] We used species inventories, trait data and a molecular dated phylogeny to calculate phylogenetic and functional community metrics. We examined the phylogenetic and functional diversity of epiphytic lichen assemblages in nine beech forests along an environmental gradient. [Results] We found a significant pattern in the average phylogenetic and functional diversity across sites. Species at northern sites were less closely related than expected by chance (phylogenetic and functional overdispersion), suggesting that these communities could be structured by species interactions limiting the similarity among them (e.g. by competition and facilitation). In contrast, species occurring in the southern distributional limit of the host tree were phylogenetically and functionally clustered, implying that these communities could be primarily structured by environmental filtering, driven by the reduction of summer rainfall. Lower precipitation areas favoured fruticulose and squamulose species and a larger proportion of species with green algal photobionts and asexual reproduction. [Conclusions] Our results suggest that environmental filtering and species interactions regulate lichen communities differently under contrasting environmental conditions in beech forests in the Iberian Peninsula. These processes are reflected by the presence of key lichen traits that are phylogenetically conserved and can provide advantages for competition or adaptation to the environment., This research was supported by the Spanish Ministry of Education and Science (project BIOFRAG, CGL2007‐66066‐C04‐4/BOS), the Ministry of Science and Innovation (project EPICON, CGL2010‐22049) and the Ministry of Economy and Competitiveness (ECOMETAS, CGL2014‐53840‐REDT).

Background and aims Onset of reproduction and reproductive allocation patterns are key components of plant reproductive strategies. Life history theory predicts that plants in adverse environments for juvenile performance start reproduction at smaller sizes and exhibit higher reproductive allocation compared to their counterparts in favourable environments. Life history theory will gain in generality if its predictions are shown to apply to a broad range of organisms and modes of reproduction. This study tested whether the asexual reproductive strategy of a lichenized fungus changed along a climatic gradient. Methods The variation in threshold size for asexual reproduction and asexual reproductive allocation of the lichen Lobarina scrobiculata was assessed in 18 populations (9665 individuals) along a climatic gradient spanning 800 km in latitude in Southern Europe. Using generalized linear models and standardized major axis regressions, the allometric relationships and the associated variation in climatic factors according to the changes in the threshold size for reproduction and reproductive allocation patterns were assessed. Key Results The onset of reproduction was size-dependent and the reproductive allocation increased with individual size. Both the threshold size for reproduction and the reproductive allocation varied along the rainfall gradient. A lower threshold size for reproduction and higher reproductive allocation in drier, adverse locations were found. Therefore, populations in drier locations fitted the predictions of life history theory for sexually reproducing organisms in adverse environments for juvenile performance. Conclusions This study highlights the applicability of the life history theory to fungi and to modes of reproduction other than sexual reproduction. Based on the intraspecific variation in the asexual reproductive strategy of a fungal organism with climatic factors, these findings expand the scope of life history theory predictions and increase our understanding of life history diversity and reproductive strategies across environments.

PREMISE OF THE STUDY Life history theory predicts that plants in unfavorable habitats for juvenile growth and survival will commence reproduction at smaller sizes and exhibit higher reproductive allocations than those in favorable habitats. The scope of life history theory will increase if these predictions apply to a broad range of organisms. Populations of organisms in contrasting habitats may experience different demographic rates. Thus, we compared the demography and life history traits of a lichen species in contrasting habitats. METHODS We compared the abundance, growth, mortality, and reproductive strategy (threshold size for reproduction and reproductive allometry) of epiphytic and saxicolous populations of the asexually reproducing lichen Lobarina scrobiculata in two oak forests in central Spain. KEY RESULTS The growth rates of saxicolous individuals were two times faster than those of epiphytic individuals. Epiphytic specimens exhibited a smaller threshold size for reproduction and a higher reproductive allocation than their saxicolous counterparts. The populations hosted by trees were two times larger than those on rocks (13,788 vs. 6629 individuals, respectively). The mortality rate did not vary between habitats. CONCLUSIONS Our results demonstrate that contrasting habitats selected for differences in the demography and life history traits of a lichen species. Consistent with life history theory predictions, in the habitat with slower growth, L. scrobiculata started to reproduce at a smaller size and its reproductive allocation was higher. This study extends the scope of life history theory and improves our understanding of life history patterns and variations in overlooked taxa such as lichens.

The main factors determining the occurrence, abundance, growth and reproductive capacity of threatened lichens need to be known in order to implement conservation ini- tiatives. The main objective of the present study was to evaluate which factors affect the conservation status of Degelia species-complex in central Spain. We undertook a non- parametric analysis to evaluate whether population sizes are larger in protected areas. We fitted generalized linear models (GLM) and mixed models (GLMMs) to analyze which variables are driving occurrence and abundance of Degelia, the thallus size and repro- duction capacity. Results show that population sizes of Degelia are very variable, being larger in broad-leaved evergreen forests and inside protected areas. Tree characteristics play an important role in its local dynamics.

Epiphytic richness is continuously declining due to forest fragmentation, logging, burning, agriculture, and livestock. The rate of species loss caused by habitat degradation and loss is more pronounced in Central and South America. Considering the extreme difficulty and time required to identify the more inconspicuous species, rapid diversity assessment methods need to be extrapolated throughout the world. This study correlated lichen growth forms and total epiphytic abundance across 119 forests located in Europe and Central-South America. A total of 54 papers were selected from specific databases focused on lichens. Additionally, data from several unpublished ecological studies were included. Linear regression models showed that epiphytic lichen abundance was highly and positively correlated with the number of growth forms at all geographical levels considered (i.e., Central-South American and European forests, and the combination of both). Thus, the use of growth forms may provide an alternative and complementary way to evaluate epiphytic diversity because most growth forms have cosmopolitan distribution and are easily recognizable.

The current trend of declining epiphytic richness caused by human activities (forest fragmentation, logging, agriculture, and livestock grazing) and the greater efforts required to sample and identify the most inconspicuous species have necessitated the use of indicators of the species richness. In this study, we examined the potential of predicting epiphytic lichen richness based on the richness of a single taxon (family) of the most conspicuous lichens (macrolichens) in Mediterranean woodlands. Since our working hypothesis is that the richness of some conspicuous elements is tightly connected with the total richness, we expect this connection is maintained even after composition shifts (for instance composition changes between coniferous and oak forests). In order to control the large set of confounding factors at macro- and microclimate scales our present study was conducted in 504 forest stands, which represented a wide range of Mediterranean climates, management intensity levels, canopy cover types, and tree sizes. The presence/absence of epiphytic lichens were determined in 7560 trees, which were dominated by coniferous (Pinus nigra and P. sylvestris) and oak (Quercus ilex ssp. ballota, Q. faginea, and Q. pyrenaica) species. In oak forests, the increased richness of Collemataceae and the complex known as “rest of Peltigerales” was followed by an increase in the overall epiphytic richness, whereas there was a strong positive correlation between Parmeliaceae and total epiphytic richness in coniferous forests. In both cases, the richness of these predictors increased in well-preserved forest stands with dense canopies. Thus, we propose the potential use of Parmeliaceae (for coniferous forests) and the Collemataceae and the “rest of Peltigerales” (for oak forests) as indicators in the Mediterranean region because they have a cosmopolitan distribution, grow in a wide range of environmental conditions, and are correlated with changes in the epiphytic richness caused by forest disturbances.

It is necessary to understand how environmental changes affect plant fitness to predict survival of a species, but this knowledge is scarce for lichens and complicated by their formation of sexual and asexual reproductive structures. Are the presence and number of reproductive structures in Lobaria pulmonaria, a threatened lichen, dependent on thallus size, and is their formation sequential? Does any size-dependence and sequential formation vary along a climate gradient? Generalized linear mixed models were used to explore the effect of environmental predictors on the size and presence/abundance of each reproductive structure and to determine the probability of a given-sized thallus to develop any reproductive structure. The largest individuals are more likely to develop reproductive structures, and the lichen uses a mixed strategy of early asexual reproduction and late sexual. Macro and microclimatic variables also influenced reproductive capacity. Relationships among climate conditions and lichen size and reproductive capacity can compromise the future viability of the species in the most southern populations of Europe.

PREMISE OF THE STUDY Habitat loss and forest fragmentation affect the dispersal and establishment of species. Furthermore, populations growing far from the species' optimal climate might be less viable because good-quality habitat can be scarce and easily altered by smaller changes. The lichen Pectenia plumbea has oceanic climatic requirements, so in the Mediterranean region it needs the humidity provided by well-preserved forests to thrive, but most of this habitat has disappeared and the remnants are fragmented. In central Spain, this species occupies only a small proportion of the existing forests, so we aimed to determine whether this scattered distribution is due to limitations on dispersal or establishment. METHODS We selected a Mediterranean fragmented forest surface in central Spain and extracted environmental variables from 371 plots. We modeled the presence and abundance of P. plumbea and developed species distribution models (SDMs) to detect all the suitable habitats inside the Cabaneros National Park area. KEY RESULTS Pectenia plumbea was present in most of the habitats predicted as good-quality and was generally absent from the poor-quality zones (85.9% overall success). The abundance correlated fairly well with that predicted by the SDM (67%). Both models show that P. plumbea is linked to high temperature and precipitation. CONCLUSIONS Good-quality habitat requirements for P. plumbea that are similar to oceanic conditions are found only in specific forested, stony slopes derived from historical land management. This habitat is scarce, but P. plumbea has successfully tracked all of these scattered areas via its high dispersal capacity.

The main goal of this work was to study species boundaries in the genus Pectenia and elucidate the biogeographic history of the four currently accepted species. To accomplish this, we included 92 specimens across the range of Pectenia in Europe and northern Africa. We used three nuclear loci and assessed species circumscription using two Bayesian coalescent-based methods and the Bayes Factor approach. We reviewed the value of reproductive mode and other morphological features as predictors of monophyletic groups. Our results suggest that the production of asexual propagules and sexual structures are not characterizing monophyletic groups. The genus includes two morphologically well-characterized main lineages, where one lineage is composed by two sub-lineages that are with a case of cryptic speciation explained by a biogeographic pattern. We suggest treating the two lineages as two species, which are characterized by lobe structure: Pectenia plumbea and P. atlantica. Both of these species include samples with asexual propagules and apothecia, and thus do not correspond to any of the earlier morphologically defined species. The results of the biogeographic analysis indicate that the Mediterranean basin is the most likely ancestral distribution area of P. plumbea, whereas P. atlantica probably originated in Macaronesia.