Fingerprints of environmental change on the rare mediterranean flora: a 115-year study

We empirically assessed the long‐term changes in the rare species assemblage of a Mediterranean flora, in terms of species life history traits, niche and biogeographic features, and taxonomic groups. We used a 115‐year historical record of ca. 2100 plant species occurrences in a 6250 km² region in Mediterranean France. Species were assigned to two classes of regional abundance for the years 1886 and 2001 (rare species, i.e. exhibiting one or two occurrences vs. nonrare species), and to three classes of abundance changes during 1886–2001 (decreasing/extinct, stable, increasing/immigrant). Then, we tested whether species regional abundance and species abundance change were related to their morphological and life‐history traits (life form, perenniality, height, dispersal agent, pollination mode), niche and biogeographic features (habitat specialization, level of endemism, biogeographic origin) and taxonomic group. The regional assemblage of rare species was not biologically random and significantly changed between 1886 and 2001. Species classified as rare in 1886 had a significantly higher rate of extinction in the study region during 1886–2001. The highest rate of regression/extinction was found among hydrophyte and/or water‐dispersed rare species, and among annual rare species. However, herbaceous perennial, tree and wind‐dispersed rare species significantly increased in abundance during 1886–2001. Rare species with Eurosiberian distributions, occurring at the southern margin of their range in the study region, dramatically declined or went extinct in the region during 1886–2001; whereas rare species with Mediterranean affinities remained significantly stable. We also found strong evidence for taxonomic patterns in species abundance and abundance changes from 1886 to 2001. The long‐term biological changes documented here in the rare species assemblage of a Mediterranean flora are consistent with the predicted consequences of climate and land use changes currently occurring in the Mediterranean Basin. With the potential decline or even extinction of entire taxa and the loss of southern ecotypes of widespread Eurosiberian species, both evolutionary history and speciation potential of the Mediterranean Region could be strongly altered in future decades.     

Persistence,multiple demographic strategies and conservation in long‐lived Mediterranean plants

Abstract. Persistence by longevity has been rarely considered as an alternative to regeneration by seeding for plants showing multiple demographic strategies. We propose a conceptual model of multiple demographic strategies for long‐lived plants in stable habitats, shifting from regeneration by seeding to persistence by longevity and/or vegetative reproduction, along gradients of abiotic stress or interspecific competition. Regeneration by seeding would be promoted under low abiotic stress or under low competition, whereas persistence by longevity and/or vegetative reproduction would predominate at high levels of abiotic stress or competition. We test this model with two threatened species of the Mediterranean region, the shrub Juniperus communis, a widely distributed species which maintains relict populations in the Mediterranean mountains thanks to great adult longevity and Pinguicula vallisneriifolia, a palaeo‐endemic herb relying on a perennial habit and vegetative reproduction under drought imposed stress or high competition at late successional phases. As a main consequence, multiple demographic strategies enhance a plant's ability to exploit environmental heterogeneity at different spatial (patches, localities, regions within the species’ distribution area) and temporal (individual life span, glacial‐interglacial cycles) scales. The potential of multiple demographic dynamics based on persistence and regeneration must be considered as a major ecological trait determining the long‐term viability of peripheral populations of relict species as well as the inertia against extinction of many threatened endemisms, thereby contributing to the maintenance of the high plant diversity characterizing the Mediterranean region.     

Identification of current ecosystem functional types in the Iberian Peninsula

Aim To examine the geographical patterns of the interception of photosynthetically active radiation by vegetation and to describe its spatial heterogeneity through the definition of ecosystem functional types (EFTs) based on the annual dynamics of the Normalized Difference Vegetation Index (NDVI), a spectral index related to carbon gains. Location The Iberian Peninsula. Methods EFTs were derived from three attributes of the NDVI obtained from NOAA/AVHRR sensors: the annual integral (NDVI‐I), as a surrogate of primary production, an integrative indicator of ecosystem functioning; and the intra‐annual relative range (RREL) and month of maximum NDVI (MMAX), which represent key features of seasonality. Results NDVI‐I decreased south‐eastwards. The highest values were observed in the Eurosiberian Region and in the highest Mediterranean ranges. Low values occurred in inner plains, river basins and in the southeast. The Eurosiberian Region and Mediterranean mountains presented the lowest RREL, while Eurosiberian peaks, river basins, inner‐agricultural plains, wetlands and the southeastern part of Iberia presented the highest. Eurosiberian ecosystems showed a summer maximum of NDVI, as did high mountains, wetlands and irrigated areas in the Mediterranean Region. Mediterranean mountains had autumn–early‐winter maxima, while semi‐arid zones, river basins and continental plains had spring maxima. Based on the behaviour in the functional traits, 49 EFTs were defined. Main conclusions The classification, based on only the NDVI dynamics, represents the spatial heterogeneity in ecosystem functioning by means of the interception of radiation by vegetation in the Iberian Peninsula. The patterns of the NDVI attributes may be used as a reference in evaluating the impacts of environmental changes. Iberia had a high spatial variability: except for biophysically impossible combinations (high NDVI‐I and high seasonality), almost any pattern of seasonal dynamics of radiation interception was represented in the Peninsula. The approach used to define EFTs opens the possibility of monitoring and comparing ecosystem functioning through time.     

The biology and ecology of narrow endemic and widespread plants: a comparative study of trait variation in 20 congeneric pairs

The objective of this study is to examine whether habitat, herbivory and traits related to resource acquisition, resource conservation, reproduction and dispersal differ between narrow endemic plant species and their widespread congeners. We undertook pairwise contrasts of 25 ecological characteristics and biological traits in 20 congeneric pairs of narrow endemic and widespread plant species in the French Mediterranean region. Within each pair, the two species had the same life-form, pollination mode and dispersal mode. Endemic species differed significantly from widespread congeners for a number of attributes. Endemic species occur in habitats on steeper slopes, with higher rock cover and in lower and more open vegetation than their widespread congeners. Endemic species are significantly smaller than widespread species, but show no differences in traits related to resource acquisition (specific leaf area, leaf nitrogen content, maximum photosynthetic rate) or resource conservation (leaf dry matter content). After accounting for their smaller stature, endemic species produce fewer and smaller flowers with less stigma-anther separation and lower pollen/ovule ratios and produce fewer seeds per plant than their widespread congeners. No consistent variation in seed mass and propagule structure was found between congeneric species. Herbivory levels did not differ between congeneric species. Ecological characteristics, notably the occupation of rocky habitats with low aboveground competition, may thus have played an important role in the differentiation of narrow endemic species in the Western Mediterranean. Morphological and ecophysiological traits of narrow endemic species indicate that they are not more stress-tolerant than their widespread congeners. Lower investment in pollen transfer and seed production suggest that local persistence is a key feature of the population ecology of narrow endemic species.     

Limited contemporary gene flow and high self‐replenishment drives peripheral isolation in an endemic coral reef fish

Extensive ongoing degradation of coral reef habitats worldwide has lead to declines in abundance of coral reef fishes and local extinction of some species. Those most vulnerable are ecological specialists and endemic species. Determining connectivity between locations is vital to understanding recovery and long‐term persistence of these species following local extinction. This study explored population connectivity in the ecologically‐specialized endemic three‐striped butterflyfish (Chaetodon tricinctus) using mt and msatDNA (nuclear microsatellites) to distinguish evolutionary versus contemporary gene flow, estimate self‐replenishment and measure genetic diversity among locations at the remote Australian offshore coral reefs of Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI), and Norfolk Island (NI). Mt and msatDNA suggested genetic differentiation of the most peripheral location (NI) from the remaining three locations (MR, ER, LHI). Despite high levels of mtDNA gene flow, there is limited msatDNA gene flow with evidence of high levels of self‐replenishment (≥76%) at all four locations. Taken together, this suggests prolonged population recovery times following population declines. The peripheral population (NI) is most vulnerable to local extinction due to its relative isolation, extreme levels of self‐replenishment (95%), and low contemporary abundance.     

Modelling riparian forest distribution and composition to entire river networks

Aim: Developing a methodology to map the distribution of riparian forests to entire river networks and determining the main environmental factors controlling their spatial patterns. Location: Cantabrian region, northern Spain. Methods: We mapped the riparian forests at a physiognomic and phytosociological level by delimiting riparian zones and generating vegetation distribution models based on remote sensing data (Landsat 8 OLI and LiDAR PNOA). We built virtual watersheds to define a spatial framework where the catchment environmental information can be specified for each river reach, in combination with the vegetation map. In order to determine the drivers that play a significant role in the observed spatial patterns in riparian forests, based on our data sets we modelled interactions between environmental information and riparian vegetation by using the Random Forest algorithm. Results: The modelling results obtained reliably reproduced the variation of riparian forest structure and composition across Cantabrian watersheds. The produced maps were highly accurate, with a more than 70% overall accuracy for forest occurrence. A clear differentiation between Eurosiberian (habitats 91E0 and 9160) and Mediterranean (92E0) riparian forests was shown on both sides of the mountain range. Topography and land use were the main drivers defining the distribution of riparian forest as a physiognomic unit. In turn, altitude, climate and percentage of pasture were the most relevant factors determining their composition (phytosociological approach). Conclusions: Our study confirms that anthropic control ultimately defines the distribution of vegetation in the riparian area at a regional to local scale. Human disturbances constrain the extension of forest patches across their potential distribution defined by topoclimatic boundaries, which establish a clear limit between Mediterranean and Eurosiberian biogeographical regions.     

Effects of regional climate and small‐scale habitat quality on performance in the relict species Ramonda myconi

Abstract. The Mediterranean Basin harbours paleo‐endemic species with a highly restricted and fragmented distribution. Many of them might also be of the remnant type, for which the regional dynamics depends on the persistence of extant populations. Therefore, a key issue for the long‐term persistence of these species is to assess the variability and effects of ecological factors determining plant performance. We investigated the spatio‐temporal variability in plant traits and ecological factors of Ramonda myconi, a preglacial relict species with remnant dynamics, in 5 populations over 4–7 yr. Ecological factors contributing to fecundity showed a high degree of between‐year variability. Pre‐dispersal fruit predation had a minor influence on total reproductive output, and most of the variability was found among individuals within populations and years. Spatio‐temporal variability in growth and survival was rather low but significant, whereas recruitment showed important between‐population variability. Among‐year variability in fecundity and growth was related to climatic fluctuations on a regional scale, notably rainfall and temperature in a particular period, while the spatial variability in survival and recruitment was explained by within‐population (patch) habitat quality. Although R. myconi is able to withstand repeated periods of drought, water availability seems to be the most important factor affecting plant performance in all the study populations. These findings suggest that the long‐term persistence of species showing remnant population dynamics in habitats under the influence of Mediterranean climate might be threatened by increased aridity as a result of climate change.     

Rarity and extinction risk in coral reef angelfishes on isolated islands: interrelationships among abundance, geographic range size and specialisation

Determining the species most vulnerable to increasing degradation of coral reef habitats requires identification of the ecological traits that increase extinction risk. In the terrestrial environment, endemic species often face a high risk of extinction because of an association among three traits that threaten species persistence: small geographic range size, low abundance and ecological specialisation. To test whether these traits are associated in coral reef fishes, this study compared abundance and specialisation in endemic and widespread angelfishes at the remote Christmas and Cocos Islands in the Indian Ocean. The interrelationships among traits conferring high extinction risk in terrestrial communities did not apply to these fishes. Endemic angelfishes were 50–80 times more abundant than widespread species at these islands. Furthermore, there was no relationship between abundance and ecological specialisation. Endemic species were not more specialised than widespread congeners and endemics used similar resources to many widespread species. Three widespread species exhibited low abundance and some degree of specialisation, which may expose them to a greater risk of local extinction. For endemic species, high abundance and lack of specialisation on susceptible habitats may compensate for the global extinction risk posed by having extremely small geographic ranges. However, recent extinctions of small range reef fishes confirm that endemics are not immune to the increasing severity of large-scale disturbances that can affect species throughout their geographic range.     

Inconsistent detection of extinction debts using different methods

The extinction debt, delayed species extinctions following landscape degradation, is a widely discussed concept. But a consensus about the prevalence of extinctions debts is hindered by a multiplicity of methods and a lack of comparisons among habitats. We applied three contrasting species–area relationship methods to test for plant community extinction debts in three habitats which had different degradation histories over the last century: calcareous grassland, heathland and woodland. These methods differ in their data requirements, with the first two using information on past and current habitat area alongside current species richness, whilst the last method also requires data on past species richness. The most data‐intensive, and hence arguably most reliable method, identified extinction debts across all habitats for specialist species, whilst the other methods did not. All methods detected an extinction debt in calcareous grassland, which had undergone the most severe degradation. We conclude that some methods failed to detect an extinction debt, particularly in habitats that have undergone moderate degradation. Data on past species numbers are required for the most reliable method; as such data are rare, extinction debts may be under‐reported.     

Fish species richness in spring‐fed ponds: effects of habitat size versus isolation in temporally variable environments

1. Species richness in a habitat patch is determined by immigration (regional) and extinction (local) processes, and understanding their relative importance is crucial for conservation of biodiversity. In this study, we applied the Island Biogeography concept to spring ponds connected to a river in southwestern Japan to examine how immigration and extinction processes interact to determine fish species richness in temporally variable environments. 2. Fish censuses were conducted 15 times in 13 study ponds at 1–4 month intervals from August 1998 through October 2000. Effects of habitat size (pond area), isolation (distance from the river) and temporal environmental variability (water level fluctuation) on (i) species richness, (ii) immigration and extinction rates and (iii) population size and persistence of each fish species were assessed. 3. The results revealed predominant effects of distance on species richness, immigration/extinction rates and population size and persistence. Species richness decreased with increasing distance but was not related to either pond area or water level fluctuation. A negative effect of distance on immigration rate was detected, while neither pond area nor water level fluctuation had significant effects on extinction rate. Further, population size and persistence of four species increased with decreasing distance, suggesting that, in ponds close to the river, immigrants from the river reduce the probability of extinction (i.e. provide a rescue effect), contributing to the maintenance of high species richness. 4. Overall results emphasise the importance of immigration processes, rather than extinction, in shaping patterns of species richness in our system. The predominant importance of immigration was probably because of (i) high temporal variability that negates habitat‐size effects and (ii) continuous immigration that easily compensates for local extinctions. Our results suggest that consideration of regional factors (e.g. connectivity, locations of source populations and barriers to colonisation) is crucial for conservation and restoration of local habitats.     

Comparison of reintroduction and enhancement effects on metapopulation viability

Metapopulation viability depends upon a balance of extinction and colonization of local habitats by a species. Mechanisms that can affect this balance include physical characteristics related to natural processes (e.g. succession) as well as anthropogenic actions. Plant restorations can help to produce favorable metapopulation dynamics and consequently increase viability; however, to date no studies confirm this is true. Population viability analysis (PVA) allows for the use of empirical data to generate theoretical future projections in the form of median time to extinction and probability of extinction. In turn, PVAs can inform and aid the development of conservation, recovery, and management plans. Pitcher's thistle (Cirsium pitcheri) is a dune endemic that exhibited metapopulation dynamics. We projected viability of three natural and two restored populations with demographic data spanning 15–23 years to determine the degree the addition of reintroduced population affects metapopulation viability. The models were validated by comparing observed and projected abundances and adjusting parameters associated with demographic and environmental stochasticity to improve model performance. Our chosen model correctly predicted yearly population abundance for 60% of the population‐years. Using that model, 50‐year projections showed that the addition of reintroductions increases metapopulation viability. The reintroduction that simulated population performance in early‐successional habitats had the maximum benefit. In situ enhancements of existing populations proved to be equally effective. This study shows that restorations can facilitate and improve metapopulation viability of species dependent on metapopulation dynamics for survival with long‐term persistence of C. pitcheri in Indiana likely to depend on continued active management.     

Habitat selection and diet of Western Capercaillie Tetrao urogallus in an atypical biogeographical region

Ecological features and conservation requirements of populations at the latitudinal limits of a species’ geographical range frequently differ from those in other parts of the range. Identifying such differences is key to implementing effective conservation strategies for threatened range‐edge populations especially, in the context of rapid global warming, at the lower‐latitude range edge. We studied habitat selection and diet of the endangered Cantabrian Capercaillie Tetrao urogallus cantabricus in a recently discovered population at the southernmost edge of the sub‐species’ range. This is the only Western Capercaillie population in the Mediterranean biogeographical region. We combined non‐systematic surveys based on questionnaires, reports and field sampling with data from radiotracking to assess habitat selection. Diet was surveyed by micro‐histological methods from droppings collected in the new population, which inhabits Pyrenean Oak Quercus pyrenaica forests and Scots Pine Pinus sylvestris plantations, and in two Cantabrian populations inhabiting Eurosiberian forests. Capercaillie preferred large (> 500 ha) and medium‐sized (100–500 ha) Pyrenean Oak forest fragments and large Scots Pine plantations. Forest fragments smaller than 100 ha and non‐forested habitats were always avoided. Diet differed markedly between Mediterranean and Eurosiberian populations. Bilberry Vaccinium myrtillus is common in the diet of most Capercaillie populations but was scarce in the study area and so was rare in the diet of the new population. Instead, Rockrose Halimium lasianthum was described for the first time as a major food resource for the Capercaillie and was consumed in autumn and winter. Pine needles were also heavily consumed in winter. We document for the first time the strong preference of Capercaillie for Pyrenean Oak forests and a moderately high consumption of the leaves, buds and acorns of this tree species throughout the year. Habitat selection and diet of this Mediterranean population differ from those of the core Cantabrian and other populations. Our results suggest a wider environmental tolerance (phenotypic plasticity) in the species than previously recognized. We advocate specific protection for this unique range‐edge Capercaillie population and its Pyrenean Oak forest habitat.     

Disturbance,microclimate and historical habitat connectivity determine the population performance of the threatened grassland specialist Carex caryophyllea in remnant grasslands

Many grassland specialist plant populations in Europe have become restricted to remnant habitats. The performance of these populations depends on both species‐specific traits and local and landscape level aspects of habitat quality. Understanding which specific local or landscape level conditions determine the performance of grassland species populations in remnant habitats would help design the restoration of the habitats and to detect the conditions that favour the long‐term persistence of grassland species in them. Such information is especially needed in urbanised landscapes, where remnant habitats engulfed by urban land use types may experience increased erosion, higher temperatures and invasion by alien species. This study investigates the population performance determinants of Carex caryophyllea (VU), a grassland specialist, in 43 remnant grasslands in an urban‐rural gradient in Finland. The population performance was assessed with metrics of persistence, establishment and reproduction, and related to environmental conditions with generalized additive models and redundancy analysis. The most important positive determinants for the performance of C. caryophyllea populations were disturbance through management or ground erosion, a warm microclimate, large habitat area and high historical connectivity to suitable grassland habitats. Present connectivity to other C. caryophyllea populations had a weak and near‐significant positive relationship with population performance. Urbanisation of the surrounding landscape correlated with population performance as well, possibly due to the high historical cover of grasslands in presently urbanised landscapes. The results imply that the most effective restoration method of remnant C. caryophyllea populations would be reinstating disturbance regimes in overgrown habitats with warm microclimates close to suitable habitats and other existing populations, whether urban or rural. This would counteract the species future decline due to possible extinction debts and help the species persist in the study area in the long term.     

How local extinction changes rarity: an example with Sonoran Desert fishes

That spatially rare species may be predisposed to extinction is a common tenet of ecology. However, the opposite side of the relationship – how extinction alters spatial rarity – remains little explored. We used an extensive biodiversity database to contrast patterns of spatial rarity of a biogeographic assemblage of native Sonoran fishes before and after an extensive, decades-long wave of extirpations. Focusing on 25 fish species native to the Lower Basin of the Colorado River, we analyzed two key aspects of spatial rarity: 1) species range sizes (expressed as kilometers of stream reach occupied) and 2) species' co-occurrence patterns. Native fish species that were spatially rare historically suffered disproportionate losses in occurrences. However, endemic species did not suffer increased losses relative to non-endemic (but still native) species of comparable rarity. Species' geographic range sizes were concordant through time, with spatially rare species remaining rare after extensive extirpations relative to species that were historically more widespread. In contrast, extirpations greatly disrupted patterns of species co-occurrence on both local and regional scales. Over 50% of the species pairs that historically co-occurred (in the same 5  km reach) no longer co-occur anywhere in the Lower Basin, and species pairs that infrequently co-occurred in historic times suffered greater proportional losses than did more widely co-occurring pairs. Such changes in the relationship between spatial rarity and species richness deserve attention because they inhibit conservation planning (decreasing the efficiency of reserve design) and reduce interaction diversity altering opportunities for long-term co-evolutionary change.     

Topo‐climatic microrefugia explain the persistence of a rare endemic plant in the Alps during the last 21 millennia

Ongoing rapid climate change is predicted to cause local extinction of plant species in mountain regions. However, some plant species could have persisted during Quaternary climate oscillations without shifting their range, despite the limited evidence from fossils. Here, we tested two candidate mechanisms of persistence by comparing the macrorefugia and microrefugia (MR) hypotheses. We used the rare and endemic Saxifraga florulenta as a model taxon and combined ensembles of species distribution models (SDMs) with a high‐resolution paleoclimatic and topographic dataset to reconstruct its potential current and past distribution since the last glacial maximum. To test the macrorefugia hypothesis, we verified whether the species could have persisted in or shifted to geographic areas defined by its realized niche. We then identified potential MR based on climatic and topographic properties of the landscape and applied refined scenarios of MR dynamics and functions over time. Last, we quantified the number of known occurrences that could be explained by either the macrorefugia or MR model. A consensus of two or three SDM techniques predicted absence between 14–10, 3–4 and 1 ka bp , which did not support the macrorefugia model. In contrast, we showed that S. florulenta could have contracted into MR during periods of absence predicted by the SDMs and later re‐colonized suitable areas according to the macrorefugia model. Assuming a limited and realistic seed dispersal distance for our species, we explained a large number of the current occurrences (61–96%). Additionally, we showed that MR could have facilitated range expansions or shifts of S. florulenta. Finally, we found that the most recent and the most stable MR were the ones closest to current occurrences. Hence, we propose a novel paradigm to explain plant persistence by highlighting the importance of supporting functions of MR when forecasting the fate of plant species under climate change.     

BIODIVERSITY RESEARCH: Geographical linkages between threats and imperilment in freshwater fish in the Mediterranean Basin

Aim The level of imperilment of mediterranean freshwater fish is among the highest recorded for any group of organisms evaluated to date. Here, we describe the geographical patterns in the incidence of threats affecting mediterranean freshwater fish and test whether the effects of specific threats are spatially related to the degree of imperilment of fish faunas. Location The Mediterranean Basin Biome. Methods From the IUCN Red List, we recorded the six main threats to 232 endemic freshwater fish species. We used data on fish distributions from IUCN to characterize the spatial patterns in the incidence of threats (as percentage of species affected) through multivariate statistics. We studied the relationships between threat incidence and two estimators of imperilment (proportion of species threatened and an index of extinction risk) at two spatial scales (10 × 10 km and basins) using partial least squares regressions (PLSR) that incorporated the effects of species richness and mean range size. Results The main axis of variation in the incidence of threats to freshwater fish split areas mainly affected by invasive species from those areas where species are threatened by pollution and agriculture. Wherever invasive species and water extraction were predominant threats, fish assemblages consistently tended to be more imperilled. Main conclusions As far as we know, this is the first large‐scale analysis on the spatial relationships between the incidence of threats and level of imperilment of any taxonomic group. Our results highlight the primary role of invasive species and water extraction as drivers of native fish declines in the Mediterranean Basin. Large‐scale patterns described here should be generated by local‐scale impacts of both threats on fish biodiversity, widely reported in Mediterranean areas. Because all the species under concern are endemic, control of invasive species and reducing overexploitation of freshwater resources should be conservation priorities for mediterranean freshwater systems.     

Gap analysis revealed a low efficiency of Natura 2000 network for the conservation of endemic species in Mediterranean temporary freshwater habitats

Listed and rare species are abundant in temporary freshwater habitats. Among them, the endemic contingent represents a crucial conservation target particularly in the areas characterized by abundant endemic flora for which the local administrations have a high level of responsibility. The aim of this research was to test how the endemic plants found in Mediterranean temporary ponds were represented in Natura 2000 network in a biodiversity hotspot of the Mediterranean region. The results of our research at regional scale pointed out that the existing Nature 2000 sites provide a limited degree of protection and that the gap analysis should be taken into account when conservation priorities are set.     

Effects of habitat size and isolation on species immigration–extinction dynamics and community nestedness in a desert river system

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Deep phylogeographic divisions and long‐term persistence of forest invertebrates (Hexapoda: Collembola) in the North‐Western Mediterranean basin

The North‐Western Mediterranean basin is well known for its high number of relictual endemic taxa, and has been indicated as one of the world’s major biodiversity hotspots at the species level. A possible contributing factor may be long‐term persistence of populations and their prolonged stability. This study was designed to investigate the phylogeographic structure of three common species of the genus Lepidocyrtus (Hexapoda: Collembola), soil‐dwelling arthropods characterized by limited dispersal capabilities and generally associated with forest habitats. We observed a remarkable geographic structure, with numerous deeply divergent genetic lineages occupying islands as well as mainland sites with no apparent gene flow among most sites, even across distances of only tens of kilometres. The reconstructed time frame for the evolution of these lineages suggests divergence between 5 and 15 Ma. This indicates a remarkably ancient origin and long‐term persistence of individual lineages over a fine geographic scale despite the occurrence of abrupt sea level and climatic fluctuations in the area. This further suggests that currently recognized morphological species might be a serious underestimation of the true springtail biodiversity within this region.     

The influence of management history on spatial prediction of Eryngium spinalba,an endangered endemic species

Question: Spatial prediction of plant populations is essential for conservation management. This is especially true for rare and/or threatened endemic species, for which knowledge of determinants of distribution is necessary to mitigate threats and counteract decline. We therefore ask if the distribution of an endemic species can be accurately predicted by georeferenced environmental variables or, if anthropogenic variables also need to be taken into account. Location: Alps, Hautes‐Alpes, France. Methods: Potential distribution area and abundance of Eryngium spinalba were predicted with logistic regression and ordinal logistic regression, respectively, in a 57‐km² watershed. Results: Aspect, global solar radiation in March, elevation and grazing pressure were the main predictors of the probability of occurrence of Eryngium spinalba. Taking into account the persistence of agro‐pastoral activities by diachronic analysis (Napoleonic cadastral map and orthorectified photographs) improved predictions from the model and the level of spatial concordance with independent surveys. Conclusions: Niche modelling improved our understanding of the distribution of this threatened species which, in the context of land abandonment, is diminishing as a result of the decline of its favoured habitats. The key role of pastoral activities and historic continuity for its distribution and persistence was clearly demonstrated.