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PREMISE: Gypsum soils in the Mediterranean Basin house large numbers of edaphic specialists that are adapted to stressful environments. The evolutionary history and standing genetic variation of these taxa have been influenced by the geological and paleoclimatic complexity of this area and the long-standing effect of human activities. However, little is known about the origin of Mediterranean gypsophiles and the factors affecting their genetic diversity and population structure. METHODS: Using phylogenetic and phylogeographic approaches based on microsatellites and sequence data from nuclear and chloroplast regions, we evaluated the divergence time, genetic diversity, and population structure of 27 different populations of the widespread Iberian gypsophile Lepidium subulatum throughout its entire geographic range. RESULTS: Lepidium subulatum diverged from its nearest relatives ~3 million years ago, and ITS and psbA/matK trees supported the monophyly of the species. These results suggest that both geological and climatic changes in the region around the Plio-Pleistocene promoted its origin, compared to other evolutionary processes. We found high genetic diversity in both nuclear and chloroplast markers, but a greater population structure in the chloroplast data. These results suggest that while seed dispersal is limited, pollen flow may be favored by the presence of numerous habitat patches that enhance the movement of pollinators. CONCLUSIONS: Despite being an edaphic endemic, L. subulatum possesses high genetic diversity probably related to its relatively old age and high population sizes across its range. Our study highlights the value of using different markers to fully understand the phylogeographic history of plant species.

AIMS Develop and psychometrically assess the Palliative Nursing Care Quality Scale (PNCQS, escala de Calidad del Cuidado Enfermero Paliativo, CCEP, in Spanish). An interview-based qualitative study (1) was conducted to verify construct validity evidence, with psychometric properties of reliability and validity verified by two quantitative studies (2 & 3). DESIGN Quantitative instrumental, correlational, and cross-sectional study. METHODS Study 1 was carried out with 10 key informants. For Study 2, a sample of 103 nursing professionals was obtained and 176 nurses from palliative care resources in Spain participated in Study 3. Data were collected between May 2017 - May 2018. RESULTS Evidence of adequate reliability (internal consistency) and validity was found. The confirmatory factor model yielded a single latent factor for the 20 items, with adequate goodness-of-fit indices. The convergent validity data showed that the highest correlations were with the Dedication subscale of the Utrecht Work Engagement Scale and the Personal Growth subscale of Psychological Well-being, with values of 0.35 and 0.34, respectively (p

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.

Rainfall and biocrusts are important sources of temporal and spatial environmental heterogeneity and niche differentiation for annual plants, a major component of diversity in drylands. Therefore, global change processes comprising shifts in rainfall timing and drought exacerbation, together with biocrust disturbance may affect species coexistence and result in disrupted diversity patterns. In this study, we experimentally evaluated the effects of the rainfall amount and timing as well as physical biocrust disturbance and their interaction on the taxonomic, phylogenetic and functional diversity of annual plant communities on gypsum soil drylands. All diversity estimates were determined at different times during community development in each experimental unit (α), as the contribution of each experimental unit to the total diversity in each treatment (β) and as the total diversity in each treatment (γ). Rainfall timings led to changes in all diversity dimensions, with higher diversity under the typical timing. The community was quite resilient to moderate reductions in rainfall, but extreme droughts decreased the alpha and beta taxonomic, functional and phylogenetic diversities. In addition, the simultaneous occurrence of biocrust disturbance and extreme drought led to consistent collapses in all diversity dimensions, probably because the effects of water shortage were exacerbated. Observations of the community at different times during its development highlighted the importance of regenerative strategies for niche differentiation and species coexistence, and their strong dependence on global change drivers. Indeed, our experimental study demonstrated that rainfall patterns and biocrusts are key factors related to the maintenance of diversity in semiarid annual plant communities. In particular, our results highlight the key role of biocrusts in modulating the effects of drought on plant diversity and the need for integrative approaches that consider both plants and biocrusts in order to elucidate the influence of climate change on the diversity of drylands. Comunidad de Madrid (GrantNumber(s): Remedinal TE-CM: S2018/EMT-4338) Ministerio de Economía y Competitividad (GrantNumber(s): Agora-CGL2016-77417) Universidad Rey Juan Carlos (GrantNumber(s): GYPVIFUN-M2148) European Horizon 2020 Programme (GrantNumber(s): Gypworld H2020-MSCA-RISE-2007-777803)

The available range of habitats and suitable abiotic conditions like temperature and radiation tends to be narrower toward the periphery of the distribution range of species. Peripheral populations of generalist species could then be more specialized and have a smaller and differentiated realized niche (habitat niche in our study) compared to populations at the core. Likewise, patterns of microhabitat selection can differ between periphery and core. In our study, we compared niche size and microhabitat selection among core (Bulgaria) and northern peripheral (Germany, Czech Republic) populations of Lacerta viridis and estimated niche differentiation among regions. We collected data on vegetation structure and abiotic parameters at the microhabitat scale in each region. In order to compare niche size among regions and estimate niche differentiation, we built multidimensional niche hypervolumes. We applied generalized linear mixed models and model averaging, accounting for spatial autocorrelation when necessary, to analyze microhabitat differences among regions and microhabitat selection in each region. Peripheral populations were more specialized, having a smaller niche than core ones, and their niche differed from that in the core (Sorensen overlap in all comparisons

Despite the important role that biocrust communities play in maintaining ecosystem structure and functioning in drylands world-wide, few studies have evaluated how climate change will affect them. Using data from an 8-yr-old manipulative field experiment located in central Spain, we evaluated how warming, rainfall exclusion and their combination affected the dynamics of biocrust communities in areas that initially had low ( 50%, HIBC plots) biocrust cover. Warming reduced the richness (35 ± 6%), diversity (25 ± 8%) and cover (82 ± 5%) of biocrusts in HIBC plots. The presence and abundance of mosses increased with warming through time in these plots, although their growth rate was much lower than the rate of lichen death, resulting in a net loss of biocrust cover. On average, warming caused a decrease in the abundance (64 ± 7%) and presence (38 ± 24%) of species in the HIBC plots. Over time, lichens and mosses colonized the LIBC plots, but this process was hampered by warming in the case of lichens. The observed reductions in the cover and diversity of lichen-dominated biocrusts with warming will lessen the capacity of drylands such as that studied here to sequester atmospheric CO2 and to provide other key ecosystem services associated to these communities.

PREMISE OF THE STUDY Verrucariaceae is a fascinating lineage of lichenized fungi for which generic and species delimitation is problematic due to the scarcity of discriminating morphological characters. Members of this family inhabit rocks, but they further colonize soils, barks, mosses, and other lichens. Our aim is to contribute to the DNA-based inference of the Verrucariaceae tree of life and to investigate characters that could be useful for proposing a more natural classification. We focused on catapyrenioid genera, which are often part of biological soil crusts, a cryptogam-dominated ecosystem contributing to soil formation and stabilization in arid environments. Understanding their evolution and taxonomy is essential to assess their roles in these fragile and important ecosystems. METHODS A multigene phylogeny of Verrucariaceae including catapyrenioid genera is presented. We further examined the phylogenetic relationships among members of Heteroplacidium and Placidium. The evolution of selected characters was inferred using the latter phylogeny. KEY RESULTS Anthracocarpon and Involucropyrenium were closely related to Endocarpon. Placidium comprised two monophyletic clades sister to Heteroplacidium. Inferred ancestral states of diagnostic characters revealed that the type of medulla and the pycnidia location were homoplasious within the Placidium clade. In contrast, the presence of rhizines was a synapomorphy for Clavascidium. CONCLUSIONS Our results provide new information on the usefulness of characters for delineating groups in Verrucariaceae. Taxonomic changes are proposed to reflect more natural groupings: Heteroplacidium podolepis is transferred to Placidium, and Clavascidium is recognized as a different genus. Eight new combinations are proposed for Clavascidium.

Recent molecular phylogenetic analyses and morphological Studies have shown that it is necessary to revise the present morphology-based generic delineation of the lichen family Verrucariaceae in or ...