Modelling the spread and control of <Emphasis Type="Italic">Xylella fastidiosa</Emphasis> in the early stages of invasion in Apulia,Italy

Xylella fastidiosa is an important plant pathogen that attacks several plants of economic importance. Once restricted to the Americas, the bacterium, which causes olive quick decline syndrome, was discovered near Lecce, Italy in 2013. Since the initial outbreak, it has invaded 23,000 ha of olives in the Apulian Region, southern Italy, and is of great concern throughout Mediterranean basin. Therefore, predicting its spread and estimating the efficacy of control are of utmost importance. As data on this invasive infectious disease are poor, we have developed a spatially-explicit simulation model for X. fastidiosa to provide guidance for predicting spread in the early stages of invasion and inform management strategies. The model qualitatively and quantitatively predicts the patterns of spread. We model control zones currently employed in Apulia, showing that increasing buffer widths decrease infection risk beyond the control zone, but this may not halt the spread completely due to stochastic long-distance jumps caused by vector dispersal. Therefore, management practices should aim to reduce vector long-distance dispersal. We find optimal control scenarios that minimise control effort while reducing X. fastidiosa spread maximally—suggesting that increasing buffer zone widths should be favoured over surveillance efforts as control budgets increase. Our model highlights the importance of non-olive hosts which increase the spread rate of the disease and may lead to an order of magnitude increase in risk. Many aspects of X. fastidiosa disease invasion remain uncertain and hinder forecasting; we recommend future studies investigating quantification of the infection growth rate, and short and long distance dispersal.     

Cold tolerance and invasive potential of the redbay ambrosia beetle (<Emphasis Type="Italic">Xyleborus glabratus</Emphasis>) in the eastern United States

Native Lauraceae (e.g. sassafras, redbay) in the southeastern USA are being severely impacted by laurel wilt disease, which is caused by the pathogen Raffaelea lauricola T. C. Harr., Fraedrich and Aghayeva, and its symbiotic vector, the redbay ambrosia beetle (Xyleborus glabratus Eichhoff). Cold temperatures are currently the only viable limitation to the establishment of X. glabratus in northern populations of sassafras. The observed lower lethal temperature of X. glabratus (? 10.0 °C) is warmer than its supercooling point (? 22.0 °C), indicating the beetle is a freeze intolerant and chill susceptible species. Empirically derived X. glabratus lower lethal temperature thresholds were combined with host distribution and microhabitat-corrected climate data to produce species distribution models for X. glabratus in the eastern USA. Macroclimate data (30-year mean annual minimum temperature) were corrected (? 1.2 °C) to account for thermal buffering afforded to X. glabratus while living inside sassafras trees. Only 0.1% of the current US sassafras spatial extent experiences sufficiently harsh winters (locales where mean annual minimum winter temperatures ≤ ? 6.2 °C for ≥ 12 h) to exclude X. glabratus establishment in our species distribution model. Minimum winter temperatures will likely cause some X. glabratus mortality in ~ 52% of the current spatial extent of sassafras, although current data do not allow a quantification of X. glabratus mortality in this zone. Conversely, ~ 48% of the current spatial extent of sassafras is unlikely to experience sufficiently cold winter temperatures to cause any significant impediment to X. glabratus spread or establishment. A modest climate change scenario (RCP4.5) of + 1.4 °C would result in 91% of the current spatial extent of sassafras in the eastern USA occurring where winter minimum temperatures are unlikely to cause any mortality to X. glabratus.     

Spatial distribution of <Emphasis Type="Italic">Vachellia karroo</Emphasis> in Zimbabwean savannas (southern Africa) under a changing climate

Climate change projections in southern Africa show a drier and a warmer future climate. It is not yet clear how these changes are going to affect the suitable habitat of bush encroacher woody species in southern African savannas. Maximum Entropy niche modelling technique was used to test the extent to which climate change is likely to affect the suitable habitat of Vachellia karroo in Zimbabwe based on six Global Climate Models (GCMs) from Coupled Model Intercomparison Project Phase 5 (CMIP5) and two Representative Concentration Pathways (RCPs) for the 2070s. An overlay analysis was then performed in a Geographic Information System based on the current and future bioclimatically suitable areas for the respective GCMs and RCPs. This was done to determine the potential effect of climate change on the focal species. Results show that temperature related variables are more important in explaining the spatial distribution of V. karroo than precipitation related variables. In addition, results indicate an overall increase in the modelled suitable habitat for V. karroo by the 2070s across the GCMs and RCPs considered in this study. Specifically, the suitable habitat of V. Karroo is projected to increase by a maximum of 57,594 km² signifying a 69% increase from the current suitable habitat (83,674 km²). The suitable areas are projected to increase in eastern, western and south eastern parts of Zimbabwe. These results imply that improved understanding of the response of woody species to a changing climate is important for managing bush encroachment in savanna ecosystems.     

Integrating genetics and suitability modelling to bolster climate change adaptation planning in Patagonian <Emphasis Type="Italic">Nothofagus</Emphasis> forests

We investigated the impact of past changes in habitat suitability on the current patterns of genetic diversity of two southern beeches (Nothofagus nervosa and Nothofagus obliqua) in their eastern fragmented range in Patagonian Argentina, and model likely future threats to their population genetic structure. Our goal was to develop a spatially-explicit strategy for guiding conservation and management interventions in light of climate change. We combined suitability modelling under current, past (Last Glacial Maximum ~ 21,000 bp), and future (2050s) climatic conditions with genetic characterization data based on chloroplast DNA, isozymes, and microsatellites. We show the complementary usefulness of the distribution of chloroplast haplotypes and locally common allelic richness calculated from microsatellite data for identifying the locations of putative glacial refugia. Our findings suggest that contemporary hotspots of genetic diversity correspond to convergence zones of different expansion routes, most likely as a consequence of admixture processes. Future suitability predictions suggest that climate change might differentially affect both species. All genetically most diverse populations of N. nervosa and several of N. obliqua are located in areas that may be most severely impacted by climate change, calling for forward-looking conservation interventions. We propose a practical spatially- explicit strategy to target conservation interventions distinguishing priority populations for (1) in situ conservation (hotspots of genetic diversity likely to remain suitable under climate change), (2) ex situ conservation in areas where high genetic diversity overlaps with high likelihood of drastic climate change, (3) vulnerable populations (areas expected to be negatively affected by climate change), and (4) potential expansion areas under climate change.     

Climate-induced shifts in the niche similarity of two related spadefoot toads (genus <Emphasis Type="Italic">Pelobates</Emphasis>)

Of the four species encompassing the genus Pelobates, only two overlap along a narrow contact zone, i.e., Pelobates fuscus and Pelobates syriacus. Our study investigated the shifts in niche similarity of these two closely related species from the Last Interglacial towards the end of the twenty-first century. We computed climatic suitability models using Maxent and projected them onto future and past climates. We used fossil occurrences to test the predictive accuracy of past projections. Niche similarity was assessed between the studied species using Schoener’s D index and a background similarity test. Finally, we evaluated niche differentiation by contrasting the species occurrences using a logistic regression analysis. The ecological niches are slightly extended outside the present geographical ranges in the Caucasus and the Balkans, south for P. fuscus and north and west for P. syriacus, suggesting that their present distribution is not at equilibrium with the climate. The Last Interglacial distribution of P. fuscus included British Isles and broad areas in western, central, and northern Europe, while P. syriacus extended northwards in the Balkans. The validation with fossil records revealed good predictive performance (omission error?=?4.1 % for P. fuscus and 16.6 % for P. syriacus). During the Last Glacial Maximum, climatic suitability persisted in refugia in southern Europe, Pannonian Basin, and Caucasus for P. fuscus, and Israel, southern Balkans, and Caucasus for P. syriacus. Present potential distributions revealed a low similarity of species’ ecological niches, comparable with Last Interglacial, but projections towards 2080 revealed a sharp increase.     

Adaptive phenotypic plasticity and competitive ability deployed under a climate change scenario may promote the invasion of <Emphasis Type="Italic">Poa annua</Emphasis> in Antarctica

Antarctica is one of the less prone environments for plant invasions, nevertheless a growing number of non-native species have been registered in the last decades with negative effects on native flora. Here we assessed adaptive phenotypic plasticity in three photoprotective traits (non-photochemical quenching, total soluble sugars, and de-epoxidation state of xanthophylls cycle), and fitness-related traits (maximum quantum yield, photosynthetic rate and total biomass) in the invasive species Poa annua and Deschampsia antarctica under current conditions of water availability and those projected by climate change models. In addition, two manipulative experiments in controlled and field conditions were conducted to evaluate the competitive ability and survival of both species under current and climate change conditions. Moreover, we performed an experiment with different water availabilities to assess cell damage as a potential mechanism involved in the competitive ability deployed in both species. Finally, was assessed the plasticity and biomass of both species subject to factorial abiotic scenarios (water × temperature, and water × nutrients) ranging from current to climate change condition. Overall, results showed that P. annua had greater phenotypic plasticity in photoprotective strategies, higher performance, and greater competitive ability and survival than D. antarctica under current and climate change conditions. Also, cell damage, assessed by lipid peroxidation, was significantly greater in D. antarctica when grown in presence of P. annua compared when grown alone. Finally, P. annua showed a greater plasticity and biomass than D. antarctica under the factorial abiotic scenarios, being more evident under a climate change scenario (i.e., higher soil moisture). Our study suggests that the high adaptive plasticity and competitive ability deployed by P. annua under current and climate change conditions allows it to cope with harsh abiotic conditions and could help explain its successful invasion in the Antarctica.     

Drivers of <Emphasis Type="Italic">Bromus tectorum</Emphasis> Abundance in the Western North American Sagebrush Steppe

Bromus tectorum can transform ecosystems causing negative impacts on the ecological and economic values of sagebrush steppe of the western USA. Although our knowledge of the drivers of the regional distribution of B. tectorum has improved, we have yet to determine the relative importance of climate and local factors causing B. tectorum abundance and impact. To address this, we sampled 555 sites distributed geographically and ecologically throughout the sagebrush steppe. We recorded the canopy cover of B. tectorum, as well as local substrate and vegetation characteristics. Boosted regression tree modeling revealed that climate strongly limits the transformative ability of B. tectorum to a portion of the sagebrush steppe with dry summers (that is, July precipitation <10 mm and the driest annual quarter associated with a mean temperature >15°C) and low native grass canopy cover. This portion includes the Bonneville, Columbia, Lahontan, and lower Snake River basins. These areas are likely to require extreme efforts to reverse B. tectorum transformation. Our predictions, using future climate conditions, suggest that the transformative ability of B. tectorum may not expand geographically and could remain within the same climatically suitable basins. We found B. tectorum in locally disturbed areas within or adjacent to all of our sample sites, but not necessarily within sagebrush steppe vegetation. Conversion of the sagebrush steppe by B. tectorum, therefore, is more likely to occur outside the confines of its current climatically optimal region because of site-specific disturbances, including invasive species control efforts and sagebrush steppe mismanagement, rather than climate change.     

Genetic diversity of endangered orchid <Emphasis Type="Italic">Phaius australis</Emphasis> across a fragmented Australian landscape

Historical events such as colonisation, spatial distribution across different habitats, and contemporary processes, such as human-mediated habitat fragmentation can leave lasting imprints on the population genetics of a species. Orchids currently comprise 17% of threatened flora species in Australia (Environment Protection and Biodiversity Conservation Act 1999) due to the combination of fragmentation and illegal harvesting (Benwell in Recovery plan, swamp orchids Phaius australis, Phaius tancarvilliae, NSW National Parks and Wildlife Service, Sydney, 1994; Jones in A complete guide to native orchids of Australia including the island territories, 2nd edn, Reed Natural History, Sydney, 2006; DE in Phaius australis in species profile and threats database, Department of the Environment. http://www.environment.gov.au/sprat, 2015). The federally endangered Swamp Orchid Phaius australis has a disjunct distribution across an almost 2000 km latitudinal range along Australia’s east coast but it was estimated that 95% of the populations have been lost since European settlement (Benwell 1994). Phaius australis is endangered due to illegal collection and habitat loss that has resulted in limited connectivity between populations, in ecosystems that are vulnerable to climate change. Thus the genetic impacts of its history combined with more recent fragmentation may have impacts on its future viability especially in light of changing environmental conditions. Thirty-four populations were sampled from tropical north Queensland to the southern edge of the subtropics in New South Wales. Population genetics analysis was conducted using 13 polymorphic microsatellite markers developed for the species using NextGen sequencing. Spatial genetic patterns indicate post-colonisation divergence from the tropics southwards to its current climate niche limits. Genetic diversity is low across all populations (A?=?1.5, H _e  = 0.171), and there is little evidence of genetic differentiation between regions. Consistent with population genetic theory, the historic loss of populations has resulted in significantly lower genetic diversity in small populations compared to large (P, A, He; p?<?0.05). The viability and persistence of P. australis populations now and in a changing climate are discussed in the context of conservation priorities.     

Geographic distribution of phylogenetic species of the <Emphasis Type="Italic">Fusarium graminearum</Emphasis> species complex and their 8-ketotrichothecene chemotypes on wheat spikes in Iran

Isolates of the Fusarium graminearum species complex (FGSC, n = 446) were collected from wheat spikes from northern and western regions of Iran with a history of Fusarium head blight (FHB) occurrences. The trichothecene mycotoxin genotypes/chemotypes, the associated phylogenetic species, and geographical distribution of these isolates were analyzed. Two phylogenetic species, Fusarium asiaticum and F. graminearum, were identified and were found to belong to sequence characterized amplified region (SCAR) groups V and I. Isolates from F. asiaticum species lineage 6 were within SCAR group V, whereas F. graminearum species lineage 7 were of SCAR group I. Of the 446 isolates assayed, 274 were F. asiaticum species predominantly of the nivalenol (NIV) genotype, while other isolates were either deoxynivalenol (DON) plus 3-acetyldeoxynivalenol (3-AcDON) or DON plus 15-acetyldeoxynivalenol (15-AcDON) genotype. Based on Tri7 gene sequences, a new subpopulation of 15-AcDON producers was observed among F. asiaticum strains in which 11-bp repeats were absent in the Tri7 sequences. The trichothecene chemotype was confirmed and quantified by high-performance liquid chromatography (HPLC) in 46 FGSC isolates. Isolates produced NIV (33.4–108.2 μg/g) and DON (64.7–473.6 μg/g) plus either 3-AcDON (51.4–142.4 μg/g) or 15-AcDON (24.1–99.3 μg/g). Among FGSC isolates, F. asiaticum produced the highest levels of trichothecenes. Using BIOCLIM based on the climate data of 20-year during 1994–2014, modelling geographical distribution of FGSC showed that F. asiaticum was restricted to warmer and humid areas with a median value of mean annual temperature of about 17.5 °C and annual rainfall of 658 mm, respectively (P < 0.05). In contrast, F. graminearum (only 15-AcDON producers) was restricted to cooler and drier areas, with a median value of the mean annual temperature of 14.4 °C and an annual rainfall of 384 mm, respectively (P < 0.05). Based on climate parameters at anthesis, the recorded distribution of F. graminearum and F. asiaticum was similar to that based on BIOCLIM parameters. Therefore, geographic differences on the wheat-growing areas in Iran have had a significant effect on distribution of FGSC and their trichothecene chemotypes.     

A first report on coexistence and hybridization of <Emphasis Type="Italic">Mytilus trossulus</Emphasis> and <Emphasis Type="Italic">M. edulis</Emphasis> mussels in Greenland

Semi-sessile Mytilus mussels are used as indicators of climate changes, but their geographic distribution is not sufficiently known in the Arctic. The aim of this study was to investigate the taxonomic status and genetic differentiation of Mytilus populations in a Northwest Greenlandic fjord at Maarmorilik, impacted by contaminations from a former mine. In this study, mussels were collected at three sites differing in exposure to environmental factors. A total of 54 polymorphic SNPs found in the Mytilus EST and DNA sequences analyzed were successfully applied to 256 individuals. The results provided the first evidence for the existence of M. trossulus in Greenland. The mussel from M. trossulus and M. edulis taxa are shown to coexist and hybridize in the fjord. The three studied sites were found to differ significantly in the distribution of taxa with a higher prevalence of M. trossulus in the inner fjord. The identified M. edulis × M. trossulus hybrids mostly had a hybrid index score of about 0.5, indicating a similar number of alleles characteristic for M. trossulus and M. edulis. There was a low number of backcrosses between ‘pure’ taxa and hybrids. This newly discovered hybrid zone between the two taxa is unique in comparison with the Canadian populations. As Mytilus mussels in Greenland hitherto have been regarded as the one taxon M. edulis, the results have importance for biogeography and future monitoring and environmental studies.     

Effects of Climate Change on <Emphasis Type="Italic">Paralaudakia lehmanni</Emphasis> (Nicolsky, 1896) (Reptilia: Agamidae) in Central Asia

Climate change and global warming are the main challenges regarding to the conservation biologists on the world. Reptiles are ectothermic animal and then highly dependent on the habitat temperature and precipitation. To protect reptiles, it is necessary to predict the impact of climate change effect on the species distribution and manage its conservation program. In this study, we aimed to evaluate the impact of climate change on the distribution pattern of Paralaudakia lehmanni in Central Asia. According to the results, the current distribution is predicted from North Afghanistan, Tajikistan, and Kyrgyzstan and the precipitation of coldest quarter (BIO19) was the most contributed bioclimate variable. Future predictions show a similar pattern with the current period and, based on the niche overlap test, the overlap of these patterns was more than 0.85 and indicated no differences between them. Distribution can be affected by the highland distribution of P. lehmanni. Because this species has such an elevated range, precipitation of coldest quarter is not predicted to change much in future and therefore suitable habitats will remain similar to current period. Finally, although there is no predicted impact of climate change on the species distribution pattern in future, the conservation of P. lehmanni is important because of other threats such as human disturbance and predation.     

Projecting present and future habitat suitability of ship-mediated aquatic invasive species in the Canadian Arctic

A rise in Arctic shipping activity resulting from global warming and resource exploitation is expected to increase the likelihood of aquatic invasive species (AIS) introductions in the region. In this context, the potential threat of future AIS incursions at a Canadian Arctic regional scale was examined. Habitat suitability under current environmental conditions and future climate change scenarios was projected for a subset of eight potential invaders ranked as having a high risk of establishment in the Canadian Arctic based on dispersal pathways/donor regions, biological attributes and invasion history: (1) Amphibalanus improvisus, (2) Botrylloides violaceus, (3) Caprella mutica, (4) Carcinus maenas, (5) Littorina littorea, (6) Membranipora membranacea, (7) Mya arenaria and (8) Paralithodes camtschaticus. Habitat modelling was performed using MaxEnt based on globally known native and non-native occurrence records and environmental ranges for these species. Results showed that under current environmental conditions the habitat is suitable in certain regions of the Canadian Arctic such as the Hudson Complex and Beaufort Sea for L. littorea, M. arenaria and P. camtschaticus. Under a future climate change scenario, all species showed poleward gains in habitat suitability with at least some regions of the Canadian Arctic projected to be suitable for the complete suite of species modelled. The use of these models is helpful in understanding potential future AIS incursions as a result of climate change and shipping at large spatial scales. These approaches can aid in the identification of high risk regions and species to allow for more focused AIS monitoring and research efforts in response to climate change.     

New and little known species of the dance-fly subgenus <Emphasis Type="Italic">Xanthempis</Emphasis> Bezzi,genus <Emphasis Type="Italic">Empis</Emphasis> L. (Diptera,Empididae), from the Caucasus

Five new species of the subgenus Xanthempis Bezzi are described from the Caucasus: Empis (Xanthempis) annae sp. n. (Russia: Krasnodar Territory), E. (X.) grichanovi sp. n. (Russia: Krasnodar Territory; Georgia), E. (X.) pseudoconcolor sp. n. (Russia: Krasnodar and Stavropol territories; Georgia: Abkhazia), E. (X.) teberdaensis sp. n. (Russia: Karachay-Cherkessia), and E. (X.) zamotajlovi sp. n. (Russia: Krasnodar Territory and Adygea). The females of E. (X.) alanica Shamshev and E. (X.) kovalevi Shamshev are described for the first time. New data on the distribution of some previously described species are reported. The geographical distribution of Xanthempis is discussed. A key to Xanthempis species from the Caucasus is compiled.     

Unraveling climate influences on the distribution of the parapatric newts <Emphasis Type="Italic">Lissotriton vulgaris meridionalis</Emphasis> and <Emphasis Type="Italic">L. italicus</Emphasis>

Background

Climate is often considered as a key ecological factor limiting the capability of expansion of most species and the extent of suitable habitats. In this contribution, we implement Species Distribution Models (SDMs) to study two parapatric amphibians, Lissotriton vulgaris meridionalis and L. italicus, investigating if and how climate has influenced their present and past (Last Glacial Maximum and Holocene) distributions. A database of 901 GPS presence records was generated for the two newts. SDMs were built through Boosted Regression Trees and Maxent, using the Worldclim bioclimatic variables as predictors.

Results

Precipitation-linked variables and the temperature annual range strongly influence the current occurrence patterns of the two Lissotriton species analyzed. The two newts show opposite responses to the most contributing variables, such as BIO7 (temperature annual range), BIO12 (annual precipitation), BIO17 (precipitation of the driest quarter) and BIO19 (precipitation of the coldest quarter). The hypothesis of climate influencing the distributions of these species is also supported by the fact that the co-occurrences within the sympatric area fall in localities characterized by intermediate values of these predictors. Projections to the Last Glacial Maximum and Holocene scenarios provided a coherent representation of climate influences on the past distributions of the target species. Computation of pairwise variables interactions and the discriminant analysis allowed a deeper interpretation of SDMs’ outputs. Further, we propose a multivariate environmental dissimilarity index (MEDI), derived through a transformation of the multivariate environmental similarity surface (MESS), to deal with extrapolation-linked uncertainties in model projections to past climate. Finally, the niche equivalency and niche similarity tests confirmed the link between SDMs outputs and actual differences in the ecological niches of the two species.

Conclusions

The different responses of the two species to climatic factors have significantly contributed to shape their current distribution, through contractions, expansions and shifts over time, allowing to maintain two wide allopatric areas with an area of sympatry in Central Italy. Moreover, our SDMs hindcasting shows many concordances with previous phylogeographic studies carried out on the same species, thus corroborating the scenarios of potential distribution during the Last Glacial Maximum and the Holocene emerging from the models obtained.

     

Stability or breakdown under climate change? A key group of woody bamboos will find suitable areas in its richness center

Bamboos play an important role in forest dynamics, but management strategies are needed to avoid monodominance. Understanding how climate change would influence the geographic distribution of bamboos could provide management tools for habitat conservation, as well as prevent the expansion of this group. We investigated the distribution patterns of Merostachys species that are endemic to the Brazilian Atlantic Forest, under current and future climate scenarios. We obtained occurrence records based on field collection, herbaria data and online databases. We used the Maxent algorithm to model potential distribution. Future scenarios considered the IPCC forecasted climate for 2070. Our models showed that a reduction in suitable areas for Merostachys species will likely occur, but the existence of suitable areas under climate changes in the Brazilian Atlantic Forest indicates climatic stability in some areas of occurrence of these species in their richness center. Since the fact that in places with local dominance of woody bamboos there is a decrease in the diversity of other plant species, the occurrence of Merostachys throughout the suitable areas may represent risks to biodiversity conservation. Investigations of the synergistic effects of climate change and the local dominance of woody bamboos are required. Therefore, management measures may be very important to control the occurrence of woody bamboos in the Brazilian Atlantic Forest, mainly in climatically stable areas.     

Spatial patterns and intraspecific diversity of the glacial relict legume species <Emphasis Type="Italic">Vavilovia formosa</Emphasis> (Stev.) Fed. in Eurasia

Vavilovia formosa is one of five genera in tribe Fabeae, (Fabaceae, Leguminosae) with close phylogenetic relationships to Pisum. It grows in subalpine and alpine levels in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia and Turkey and is recognized as an endangered and protected plant. This study was conducted to reveal its intraspecific variability, as well as to predict the past, extant and future species distribution range. We analysed 51 accessions with common phylogenetic markers (trnF-trnL, trnS-trnG, matK, rbcL, psbA-trnH and ITS). These represent in total up to 2551 bp of chloroplast and 664 bp of nuclear sequences per sample. Two populations from Turkey and Armenia were analysed for genetic diversity by AFLP. Leaf morphometry was conducted on 1457 leaflets from 43 specimens. Extracted bioclimatic parameters were used for niche-modelling approach. Analysis of cpDNA revealed two haplotypes, 12 samples from Armenia, Daghestan, Nakhichevan and Iran belonged to H1 group, while 39 samples of all Turkish and part of Armenian were in H2 group. The mean intrapopulation diversity based on AFLP was low (H _E = 0.088) indicating limited outcrossing rate. A significantly positive correlation between geographical latitude and leaf area (\(\rho\) = 0.527, p < 0.05) was found. Niche modelling has shown temporal variation of predicted occurrence across the projected time periods. Vavilovia formosa has suffered a range reduction following climate warming after last glacial maximum, which classify this species as cold-adapted among the Fabeae species as well as a glacial relict.     

Xylem anatomy and calculated hydraulic conductance of four <Emphasis Type="Italic">Nothofagus</Emphasis> species with contrasting distribution in South-Central Chile

Nothofagus obliqua, N. dombeyi, N. alpina and N. antarctica are characteristic tree species of the temperate forests on the western slopes of the Andes with centres of distribution that differ in their temperature and moisture regimes. We tested branch wood from co-occurring specimens of these species for the inherent differences in xylem anatomy and theoretical hydraulic conductance to evaluate their resistance to drought or frost. The hydraulic conductivity of the xylem was calculated using a modified Hagen–Poiseuille equation and related to wood density. Conduit dimensions were used to predict the water potential that would cause 50 % loss of hydraulic conductivity (Ψ ₅₀). Nothofagus alpina, which mainly grows at sites with low frost frequency, exhibited the largest conduits and the highest mean values for conduit area, fraction of conduit area in the cross-section and hydraulic conductivity, but the lowest wood density. Opposite relationships were found in the plastic N. antarctica, whose xylem seems to be least vulnerable to freezing-induced, but also to drought-induced embolism. Calculated Ψ ₅₀ was highest (least negative) in N. alpina, indicating a relatively high susceptibility to cavitation. The xylem of the thermophilic N. obliqua and of N. dombeyi, which mainly occurs under oceanic climate, but can also survive at sporadically dry and warm sites, is not particularly adapted to periods of drought stress. Across all species, wood density was negatively correlated with the calculated hydraulic conductance. The xylem traits of N. alpina might contribute to its relatively high growth rate and facilitate its spread into forest gaps.     

<Emphasis Type="Italic">Usnea antarctica</Emphasis>, an important Antarctic lichen,is vulnerable to aspects of regional environmental change

Studies of cryptogam responses to climate change in the polar regions are scarce because these slow-growing organisms require long-term monitoring studies. Here, we analyse the response of a lichen and moss community to 10 years of passive environmental manipulation using open-top chambers (OTCs) in the maritime Antarctic region. Cover of the dominant lichen Usnea antarctica declined by 71 % in the OTCs. However, less dominant lichen species showed no significant responses except for an increase in Ochrolechia frigida, which typically covered dying lichen and moss vegetation. There were no detectable responses in the moss or associated micro-arthropod communities to the influence of the OTCs. Based on calculated respiration rates, we hypothesise that the decline of U. antarctica was most likely caused by increased net winter respiration rates (11 %), driven by the higher temperatures and lower light levels experienced inside the OTCs as a result of greater snow accumulation. During summer, U. antarctica appears unable to compensate for this increased carbon loss, leading to a negative carbon balance on an annual basis, and the lichen therefore appears to be vulnerable to such climate change simulations. These findings indicate that U. antarctica dominated fell-fields may change dramatically if current environmental change trends continue in the maritime Antarctic, especially if associated with increases in winter snow depth or duration.     

South African mouse shrews (<Emphasis Type="Italic">Myosorex</Emphasis>) feel the heat: using species distribution models (SDMs) and IUCN Red List criteria to flag extinction risks due to climate change

Five species of mouse or forest shrews (Myosorex) are endemic to South Africa, Lesotho and Swaziland, four of which (Myosorex varius, Myosorex cafer, Myosorex longicaudatus and Myosorex cf. tenuis) are associated with montane or temperate grassland, fynbos and/or forest habitats while a fifth (Myosorex sclateri) is associated with lowland subtropical forests. Due to their small size, specialised habitat, low dispersal capacity, high metabolism and sensitivity to temperature extremes, we predicted that, particularly for montane species, future climate change should have a negative impact on area of occupancy (AOO) and ultimately extinction risks. Species distribution models (SDMs) indicated general declines in AOO of three species by 2050 under the A1b and A2 climate change scenarios (M. cafer, M. varius, M. longicaudatus) while two species (M. sclateri and M. cf. tenuis) remained unchanged (assuming no dispersal) or increased their AOO (assuming dispersal). While temperate species such as M. varius appear to be limited by temperature maxima (preferring cooler temperatures), the subtropical species M. sclateri appears to be limited by temperature minima (preferring warmer temperatures). Evidence for declines in AOO informed the uplisting (to a higher category of threat) of the Red List status of four Myosorex species to either vulnerable or endangered as part of a separate regional International Union for Conservation of Nature (IUCN) Red List assessment.     

Predicting the effects of future climate change on the distribution of an endemic damselfly (Odonata,Coenagrionidae) in subtropical South American grasslands

Climate change is predicted to affect the distribution of freshwater taxa, and stronger impacts are expected on endemic species. However, the effects of future climates on freshwater insects from the Neotropical region have been generally overlooked. In this study, the distribution of a damselfly (Cyanallagma bonariense, Odonata, Coenagrionidae) endemic to the subtropical South American grasslands (Pampa) was modelled in relation to future scenarios of high greenhouse gas emissions (RCP 8.5) for 2050 and 2070. For this purpose, ecological niche models were developed based on assumptions of limited dispersal and niche conservatism, and the projected distribution of C. bonariense was contrasted with the location of current protected areas (PAs) in the Pampa. A broad potential distribution of C. bonariense was indicated throughout the Pampa, and projections predicted a predominance of range contractions rather than range shifts in climatically suitable areas for C. bonariense in 2050 and 2070. Projections of suitable areas overlapped in central Argentina and southernmost Uruguay in these periods. Our results indicated a potential resilience of C. bonariense to future climate change, which is likely related to the low restrictions in habitat use of C. bonariense. In every projection, however, most PAs were expected to lose effectiveness, as by 2070 most PAs fall outside the range of the predicted distribution of C. bonariense. Thus, the creation or enlargement of PAs in these areas is recommended and these results represent an important information for the conservation of endemic freshwater insects under global warming scenarios in an overlooked Neotropical landscape.