Montane Sites Research Articles

Highland forest dynamics across equatorial East Africa during the end of the African humid period

Tropical mountain ecosystems hold immense ecological and economic importance, yet they face disproportionate risks from shifting tropical climates. For example, present-day montane vegetation of East Africa is characterized by different plant species that grow in and are restricted to certain elevations due to environmental tolerances. As climate changes and temperature/rainfall zones move on mountains, these species must rapidly adjust their ranges or risk extinction.Paleoenvironmental records offer valuable insights into past climate and ecosystem dynamics, aiding predictions for ongoing climate change impacts. In particular, warming and wetting in tropical East Africa during the mid-Holocene resulted in both lowland and highland forest expansion. However, the relative impacts of rainfall and temperature change on montane ecosystems along with the influence of lowland forest expansion on montane communities is not completely understood. We use fossil pollen to study the vegetation changes in two lakes at different altitudes in the Rwenzori Mountains, Uganda: Lake Mahoma (Montane Forest belt) and Upper Kachope Lake (Afroalpine belt). Further, using the newly relaunched African Pollen Database and recent temperature reconstructions, we provide a regional synthesis of vegetation changes in the Rwenzori and then compare this with changes observed from other equatorial East African montane sites (particularly Mt Kenya).In the early to mid-Holocene in the Rwenzori Mountains, trees common today in lowland forests dominated, driven largely by warmer temperatures. After 4000 years ago (4ka), Afromontane forest trees along with grasses progressively replaced lowland trees. Not all sites experienced identical transitions. For instance, at Lake Rutundu on Mt Kenya at the same elevation as Lake Mahoma, bamboo expansion preceded Afromontane forest growth, likely influenced by variations in fire. Variance partitioning indicates that each site responded differently to changes in temperature and rainfall. Therefore, these site-specific ecological responses underscore the importance of considering biogeographic legacies as management strategies are developed, despite similarities in modern ecology.

Rural occupancy in a montane burrowing snake: the importance of thermal and microhabitat resources during the rainy season

Thermal and microhabitat resources are two fundamental requirements that affect the life history of any ectotherm. Furthering our understanding of how reptilian species meet these ecological requirements is crucial for assessing the impact of environmental and anthropogenic changes on populations. Here, we explored some fundamental aspects of the thermal and microhabitat ecology of Conopsis biserialis, a small, burrowing, and endemic earthsnake of central Mexico. The study was conducted during the rainy season in a montane site disturbed by rural activities. The mean field body temperature (Tb) of C. biserialis was 26 ± 0.6 ºC. Field Tb did not differ significantly between sex and development stages. However, we found that Tb was positively correlated with substrate, air, and under-rock temperatures (Ts, Ta, and Tr) in the rural microhabitat. Regression analysis showed that substrate and under-rock temperatures (Ts and Tr) were the parameters that best explained Tb variability in the individuals. The temperature and relative humidity under shelter did not differ significantly among shelter types and/or rock sizes. In addition to these thermal traits, earthsnakes selected and utilized six common biotic and physical elements of the rural microhabitat. Most individuals used high proportions of large and medium rocks for sheltering, and these rocks were selected around crop fences and cleared grasslands where the soil can be either covered with low vegetation or bare. Our results suggest that, during the rainy season, individuals of C. biserialis use and select some biotic and structural resources of the rural microhabitats, and were capable of actively regulating their temperature by using shelters with high values of microclimatic homogeneity.

Demonstration of process-based reconstruction of annual temperatures from tree ring oxygen isotope

Forecasting the global warming of the post-industrial period requires knowledge of natural variations in climatic parameters, especially temperature in preceding times. Due to its stable time resolution and known physiochemical formation process, tree ring cellulose isotope datasets have immense potential to yield climatic variability information. The first standardized site-independent temperature reconstruction model from tree-ring cellulose oxygen isotope data is demonstrated here using data from a montane site in the western Himalayas. This model does not require any statistical calibration and can be directly compared with instrumental or modelled data. The resulting temperature amplitude is dependent on moisture availability and this input is needed to modulate the reconstruction. The present work tests the possibility of input of carbon isotope discrimination as a proxy of relative humidity. This input achieved amplitude control but additional frequency components were introduced to the reconstruction.

Quantifying ant diversity and community in a subalpine forest mosaic: a comparison of two methods

Sampling efficiency, composition and detection biases associated with pitfall-trap and sample plot (standardised hand-collecting) methods were compared at seven high montane sites at Lasha Mountain, Yunnan, China. Rarefaction-interpolation curves showed total species diversity and sample coverage from each method were undifferentiated. Permutational multivariate analysis of variance showed highly overlapping communities. However, of all species collected, just 53% of all species found were shared between the two methods; 30% were exclusive to sample plot samples and 17% were exclusive to pitfall traps. Modelled comparisons of species richness (alpha) and proportion of species from the population (beta diversity) showed differences between methods. Permutational multivariate analysis of variance blocked by site showed community composition differed between methods, defined largely by the presence of a few dominant species.Implications for insect conservation: Our findings suggest that results from the two methods cannot be directly compared and are imperfect substitutes to one another. For long-term monitoring of biodiversity in complex forest mosaic systems, we suggest integrating a suite of complementary methods to achieve more complete representation of ant composition and diversity.

Managing small populations—using genetic data and trial translocations to help inform suitable conservation measures for the alpine blue-sowthistle (Cicerbita alpina) in Scotland

Habitat fragmentation is causing an increasing amount of species loss around the world and creates problems at the population level. Many species are left as only small and isolated populations, which are vulnerable to genetic erosion and inbreeding depression. Here we present a study on the alpine blue-sowthistle (Cicerbita alpina). Due to intensive grazing the species is very rare in Scotland, where it occurs at only four small, montane sites, has never been reported to reproduce and is in need of conservation interventions. As the species can grow clonally it is unknown how many individuals remain and whether populations are affected by genetic isolation. We (1) quantified genetic diversity, inbreeding and between-population differentiation in Scotland and Norway using 15 microsatellite loci, and (2) experimentally translocated plants to new sites. Genetic diversity in Scotland was low (H E: 0.35; Allelic Richness: 1.84; 4 sites) compared to Norway (H E: 0.52; Allelic Richness: 2.56; 5 sites). The transplants were able to grow at new sites and are therefore not restricted to steep, montane ledges. While grazing is likely to be the main factor preventing range expansion, long-term genetic isolation has possibly further lowered population viability. To avoid local extinction of this species, conservation translocations and genetic rescue might be appropriate conservation interventions, but this needs to be further tested in a controlled environment and away from wild sites to avoid potential risks of outbreeding depression.

Contrasting warming responses of photosynthesis in early- and late-successional tropical trees.

The productivity and climate feedbacks of tropical forests depend on tree physiological responses to warmer and, over large areas, seasonally drier conditions. However, knowledge regarding such responses is limited due to data scarcity. We studied the impact of growth temperature on net photosynthesis (An), maximum rates of Rubisco carboxylation at 25°C (Vcmax25), stomatal conductance (gs) and the slope parameter of the stomatal conductance-photosynthesis model (g1), in 10 early successional (ES) and 8 late-successional (LS) tropical tree species grown at three sites along an elevation gradient in Rwanda, differing by 6.8°C in daytime ambient air temperature. The effect of seasonal drought on An was also investigated. We found that warm climate decreased wet-season An in LS species, but not in ES species. Values of Vcmax25 were lower at the warmest site across both successional groups, and An and Vcmax25 were higher in ES compared with LS species. Stomatal conductance exhibited no significant site differences and g1 was similar across both sites and successional groups. Drought strongly reduced An at warmer sites but not at the coolest montane site and this response was similar in both ES and LS species. Our results suggest that warming has negative effects on leaf-level photosynthesis in LS species, while both LS and ES species suffer photosynthesis declines in a warmer climate with more pronounced droughts. The contrasting responses of An between successional groups may lead to shifts in species' competitive balance in a warmer world, to the disadvantage of LS trees.

Vapour pressure deficit and solar radiation are the major drivers of transpiration in montane tropical secondary forests in eastern Madagascar

Young secondary tropical forests occupy a larger area than mature forests nowadays but our understanding of their ecohydrological functioning, particularly with respect to tree water uptake, remains poor. Deep soil water uptake may make mature forests resilient to periods of water stress, but little is known in this regard for young forests with possibly less extensive root networks. We, therefore, studied sap flow dynamics for one year in two 50 m x 50 m forest plots: a young secondary forest (YSF, 5–7 years) and a semi-mature forest (SMF; 20 years) in montane eastern Madagascar. Temporal variations in the depth of water uptake were inferred from the stable isotope compositions of soil- and xylem water. Transpiration rates were low for both forest sites (265 and 462 mm y−1 for the YSF and SMF, respectively). Vapour pressure deficit and global radiation explained most of the variation in transpiration rates at both sites. There was little evidence of transpiration limitation by soil water, despite an extended dry season. Trees in the YSF extracted water mostly from the intermediate soil depth (30–70 cm) during the dry season. In the SMF, the depth of uptake increased as the dry season progressed for some species (Abrahamia, Brachylaena and Cryptocaria), but not for others (Ocotea and Eugenia). Although the transpiration rates are low for both forests, they are comparable to results reported for other tropical montane sites after normalising for net energy input and leaf area. Estimated evapotranspiration totals (including interception loss, understorey and litter evaporation) were 679 mm and 1063 mm y−1 for the YSF and SMF, respectively (42% and 61% of precipitation, respectively). These results suggest that the stage of forest regrowth affects water uptake, and thus the water balance during forest succession.

Distribution of Liana Richness and Abundance in the Forest of Papua New Guinea

This study surveys liana communities at 26 sites across undisturbed and disturbed forests from 70 to 2,700 m above sea level in northern parts of Papua New Guinea (PNG). The assessment was conducted following the Papua New Guinea National Forest Inventory (NFI) manual. The results show a total diversity of 68 genera of lianas, belonging to 33 families. No significant difference was observed in abundance of liana species between lowland unlogged (i.e., primary and pristine) and logged (disturbed) forests and lower montane unlogged forests. Richness is not significantly different between lowland and montane sites, as opposed to outcomes in other studies which have often reported a decrease in species richness with elevation. Both types of lowland forests do not show indicator genera, while the unlogged montane forests are characterized by Rubus and Sabia genera. The study shows a high taxonomic richness of lianas in PNG, supporting previous research and underlining that they make a significant contribution to the overall woody species richness and to the ecology and complexity of PNG forest.

Environmental Effects among Differently Located and Fertile Sites on Forest Basal-Area Increment in Temperate Zone

Environmental properties differently influence the growth of forest tree species. The antagonistic effects of variable environmental properties classify the forest response according to various tree compositions among different sites. The division of the forest response was assessed in 52 stands arranged into 26 types of 13 site management populations (MPs) in 5 areas in the Czech Republic territory. The assessment was performed using time-series multiple regressions of basal-area increment from pure immature stands of Norway spruce (Picea abies), Scots pine (Pinus sylvestris), oaks (Quercus sp.), ash (Fraxinus excelsior) and willows (Salix sp.) dependent on the interpolated average temperatures, annual precipitation, atmospheric concentrations of SO2, NOx and O3 and soil properties over the period 1971–2008 at p < 0.05. Site MPs differentiated the forest response to a greater extent than tree species. The response of the forests was significantly distributed by means of the montane, upland and waterlogged sites. The multiple determination index (r2) ≥ 0.6 indicated an adaptable tree increment but an interval of r2 between 0.80–0.92 implied forest sensitivity to variability in environmental properties on non-waterlogged sites. The index r2 < 0.6 suggested a fluctuating forest increment that reflects environmental variability inconsistently. The fluctuating increment most affected the spruce and pine stands grown from upland to submontane locations. Montane spruce stands, as well as rock pines, appeared to be one of the most sensitive ones to environmental change. Floodplain forests seemed as adaptable to variable environmental properties.

Litter decomposition rates across tropical montane and lowland forests are controlled foremost by climate

AbstractThe “hierarchy of factors” hypothesis states that decomposition rates are controlled primarily by climatic, followed by biological and soil variables. Tropical montane forests (TMF) are globally important ecosystems, yet there have been limited efforts to provide a biome‐scale characterization of litter decomposition. We designed a common litter decomposition experiment replicated in 23 tropical montane sites across the Americas, Asia, and Africa and combined these results with a previous study of 23 sites in tropical lowland forests (TLF). Specifically, we investigated (1) spatial heterogeneity in decomposition, (2) the relative importance of biological factors that affect leaf and wood decomposition in TMF, and (3) the role of climate in determining leaf litter decomposition rates within and across the TMF and TLF biomes. Litterbags of two mesh sizes containing Laurus nobilis leaves or birchwood popsicle sticks were spatially dispersed and incubated in TMF sites, for 3 and 7 months on the soil surface and at 10–15 cm depth. The within‐site replication demonstrated spatial variability in mass loss. Within TMF, litter type was the predominant biological factor influencing decomposition (leaves > wood), with mesh and burial effects playing a minor role. When comparing across TMF and TLF, climate was the predominant control over decomposition, but the Yasso07 global model (based on mean annual temperature and precipitation) only modestly predicted decomposition rate. Differences in controlling factors between biomes suggest that TMF, with their high rates of carbon storage, must be explicitly considered when developing theory and models to elucidate carbon cycling rates in the tropics.Abstract in Spanish is available with online material.

Diversity of Flower Visiting Beetles at Higher Elevations on the Yulong Snow Mountain (Yunnan, China)

Background: Flowers are one of the important microhabitats promoting beetle diversity, but little is known about variation in the diversity of these insects at higher elevations. We do not know how divergent habitats influence the distribution of beetles among montane flora. Methods: We sampled beetles systematically in angiosperm flowers at 12 sites at two elevations (2700 m and 3200 m) and in two habitats (meadows and forests) for two consecutive years (2018 and 2019) on the Yulong Snow Mountain in Yunnan, southwestern China. Beetle diversity among sites were compared. Their interactions with flowers of identified plant species were analyzed using bipartite networks approach. Results: We collected 153 species of beetles from 90 plant species recording 3391 interactions. While plant species richness was lower at the higher, 3200 m elevation regardless of habitat type, beetle species richness was not significantly different among sites. Plant-beetle interaction networks were strongly modular and specialized. The structure of networks showed greater differences between elevations than between habitats. The turnover of networks was determined by species composition showing a weak influence by interaction rewiring. Conclusion: Our study showed a high diversity of beetles in flowers at higher elevations within this mountain complex. The role of beetles in plant–insect interactions within some sections of temperate, montane sites appear to be underestimated and warrant further study.

High aboveground carbon stock of African tropical montane forests.

Tropical forests store 40-50per cent of terrestrial vegetation carbon1. However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests2. Owing to climatic and soil changes with increasing elevation3, AGC stocks are lower in tropical montane forests compared with lowland forests2. Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network4 and about 70per cent and 32per cent higher than averages from plot networks in montane2,5,6 and lowland7 forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa8. We find that the low stem density and high abundance of large trees of African lowland forests4 is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to helpto guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse9,10 and carbon-rich ecosystems.

UV radiation and temperature effects on functional traits in Helianthemum nummularium subsp. grandiflorum at the alpine and montane site in the Slovenian Alps

Alpine plants have evolved strategies to survive harsh conditions, which include high UV and visible radiation, extreme temperatures, dryness and lack of nutrients. Survival strategies include biochemical, physiological and morphological responses, which are scarcely studied because of the time-demanding and complex experimental conditions. We researched functional traits in the alpine plant common rockrose Helianthemum nummularium subsp. grandiflorum growing under ambient UV-B and reduced UV-B radiation at different altitudes (1600 and 2000 m a.s.l.) of mount Vogel in the Slovenian Alps. Leaf anatomy, pigments and optical properties were investigated at the beginning and at the end of the growing season. Plants showed high constitutive UV-absorbing compounds content (UV-AC) throughout the season. Most leaf thickness parameters were not altered according to UV and altitude conditions. Leaves did not transmit any UV spectrum, in agreement with high UV-AC. High photosynthetic spectrum transmittance at alpine altitudes was due to complex biochemical and anatomical responses to these conditions, rather than to UV radiation. Unchanged chlorophyll content of H. nummularium could be related to shrub life form, where leaves shade out high UV and PAR irradiance as well as contribute to lower leaf temperature. This study shows the complexity of alpine plant response, wherespecific characteristics of plant species should not be overlooked.

Two New Platynus Bonelli (Coleoptera: Carabidae: Platynini) from Nevis and St. Kitts, Lesser Antilles

Platynus (Dyscolus) racquelae Liebherr and Ivie, new species is described from the Crater Rim, in the Parish of St. John Capisterre, St. Kitts, and Platynus (Dyscolus) duportei Liebherr and Ivie, new species is described from Nevis Peak, Nevis. These species are placed in the Platynus (Dyscolus) memnonius (Dejean) group, with their addition to the group extending the group's aggregate distribution northward from Basse-Terre, Guadeloupe to St. Kitts. Based on extensive collections of the Coleoptera of St. Kitts, P. racquelae appears to be restricted to only the wettest areas at highest elevations, suggesting that this species requires rather specific conditions present only in the most extreme montane sites. The beetles also exhibit moderate flight wing reduction involving diminution of wing veins associated with wing-folding—specifically, veins associated with the wedge and oblongum cells—and foreshortening of the alar surface due to loss of membrane along the wing's apical margin. This suggests that individuals of P. racquelae are at best weak fliers, and that this species is not able to colonize isolated patches of suitable habitat by flight. Platynus duportei is likewise known from only the highest and wettest point on Nevis Peak, but this species exhibits fully developed flight wings. Additional records of Platynus (Dyscolus) luciae Liebherr from St Lucia, and of Glyptolenus chalybaeus (Dejean) are reported, allowing elucidation of flight wing configuration and male and female genitalia for the former, and new island records of Nevis and Saba for the latter.

Abiotic and biotic determinants of height growth of Picea abies regeneration in small forest gaps in the Swiss Alps

In managed mountain forests, height growth of Norway spruce (Picea abies (L.) Karst) regeneration is a decisive factor for the gap-filling process, especially when the silvicultural goal is to provide continuous protection against natural hazards such as snow avalanches or rockfall. For the planning of management interventions, robust predictions on height growth of regeneration at the scale of forest gaps are thus needed. However, there is a lack of such data for trees of intermediate sizes, and existing studies fail to cover large environmental gradients. The goal of our study is to identify the key factors that influence height growth of Norway spruce regeneration in small gaps of spruce-dominated forests in the Swiss Alps. Furthermore, we assess whether there are site-specific differences of height growth or whether it follows a similar pattern along a large gradient of temperature (i.e., along elevation) and of water and nutrient availability (i.e., among different phytosociological site types) within the upper montane and subalpine vegetation belts. On 124 plots, >2′000 observations of annual height increments of Norway spruce regeneration (10 cm tree height to 12 cm stem diameter) in gaps were collected. Using linear mixed effects models and cross-validation for model selection, we identified the best variable combinations to predict annual height growth. Consistently across the entire gradient, the most important factors were 1) the positive effect of tree size, 2) the negative effect of competition by the surrounding stand, and 3) local topography. We found site-specific differences in height growth patterns such as gap size and therefore direct radiation being the most important competition measure in subalpine sites, as opposed to diffuse radiation in high montane sites. However, the pooled model for the entire environmental gradient allowed for predictions of regeneration height growth with similar explanatory power as the more specific models while containing comparable effect sizes. Furthermore, competition can be equally well expressed by metrics based on basal area measurements as by metrics derived from hemispherical photography. Based on these relatively simple models, accurate and robust predictions of the development of Norway spruce regeneration in gaps of managed mountain forests are possible.

Ferns and Lycophytes of Gori Valley, Western Himalaya, Uttarakhand: A Case Study

This study was carried out in the Gori Valley catchment of Uttarakhand, Western Himalaya, to document more fully the distribution and ecology of ferns and lycophytes at a montane site divided into 7 elevation sampling zones from 1,800–4,000 m (subtemperate to alpine) across a distance of approximately 30 km. A total of 16 families, 33 genera, and 92 species were found. Species richness, total species density ha–1, diversity, and Pielou's species evenness per elevation zone (m) were calculated for each zone. The data were used to evaluate three hypotheses addressing changes in density and species distribution in relation to the biogeographic and climatic conditions across the seven elevation sampling zones. Total density of ferns and lycophytes tended to decrease from Zone 1 toward Zone 7; although Zones 1-3 (sub-temperate) had clearly higher mean densities than those in Zones 5-7 (alpine). The highest density was found in Zone 1 (Lilam 1,800 m) and lowest density was found in Zone 6 (Burfu 3,450 m). After finding a significant difference among all mean densities for each elevation zone (p < 0.001), using a non-parametric Welch's ANOVA, a Games-Howell test for pairwise comparisons of the means showed that each of the mean densities for species in Zones 1 to 3 was significantly different from each of the species densities in Zones 5 to 7 (p < 0.05). The mean densities for Zone 4 were not significantly different from any of the other zonal mean densities (i.e., 1–3 and 5–7), suggesting that Zone 4 is a transitional zone between two end member Zones (1–3 and 5–7).

Biogeochemical characteristics and hydroperiod affect carbon dioxide flux rates from exposed high‐elevation pond sediments

AbstractWhile inundated, small ponds (&lt; 1000 m2 area) account for disproportionately large contributions of CO2 efflux to the global carbon budget and also store carbon in anoxic sediments. However, pond hydrology is shifting toward increasingly dry conditions in alpine and temperate zones, which might lead to increased exposure of shallow pond sediments. We analyzed sediment CO2 efflux rates in dried sediments of multiple ponds of varying hydrology and sediment characteristics at montane and subalpine elevations near the Rocky Mountain Biological Laboratory in Colorado. Average CO2 efflux rates from exposed sediments, 331.5 ± 11.5 mmol m−2 d−1 at the montane sites and 142.8 ± 45.1 mmol m−2 d−1 at the subalpine sites, were 10 times higher than average CO2 efflux rates from pond water. Principal components analysis to reduce dimensionality of sediment characteristics revealed that random inter‐pond differences rather than exposure timing or hydroperiod drove variation among sediments. In linear mixed effects models of CO2 flux rates, significant predictors included sediment moisture and temperature, pH, total organic carbon, and organic matter content at all pond hydroperiod classifications and sites. However, the sediment characteristics explaining the most variance differed among sites and hydroperiods and included nitrate concentrations, pH, bulk density, and temperature. We conclude that pond sediments are heterogeneous both within and among ponds in close proximity, and drivers of relatively high CO2 efflux rates differ among pond hydroperiods and elevations. This work emphasizes that local differences can impact predictions of CO2 flux from lentic sediments which are becoming increasingly exposed.

At the end of the world? Settlement in the Šumava mountains and foothills in later prehistory

Abstract The aim of this paper is to explore and define the boundary of the zone of inland, mainly agricultural settlement in southern and western Bohemia, Czech Republic in the later prehistory, and to try to determine why such settlement appears not to have spread further into the Šumava foothills and mountains. With the help of predictive MaxEnt modelling – used in ecology to determine the degree of uncertainty in the geographic distribution of species – and using a comparison with data on soil productivity, we explore whether in later prehistory the agricultural settlement was limited by unsuitable natural conditions or by other factors. The boundaries of the territory suitable for agropastoral farming most probably moved in time with technological advances, increases in population density, and the changing preferences of inhabitants of the Bronze and Iron Ages. The margin of agricultural settlement in the foothills describes a line beyond which agriculture had become unprofitable; a similar boundary existed throughout the Early Middle Ages. At the same time, there was a good deal of contact across the mountains with Bavaria and Upper Austria, as is shown by archaeology both in the form of similarities between the prehistoric typo-chronological complexes and by finds of bronze and iron items along presumed routes of access. There were also montane sites (whose function is still unknown) situated beyond the margin of the agricultural zone, such as the recently discovered settlements on the Křemelná river. Apart from prospection, a wide range of other activities could have taken place, including those connected with communication and routes of access to Bavaria and Upper Austria, with which Šumava formed a common typo-chronological group.

Lost and found: Frogs in a biodiversity hotspot rediscovered with environmental DNA.

Declines and extinctions are increasing globally and challenge conservationists to keep pace with biodiversity monitoring. Organisms leave DNA traces in the environment, e.g., in soil, water, and air. These DNA traces are referred to as environmental DNA (eDNA). The analysis of eDNA is a highly sensitive method with the potential to rapidly assess local diversity and the status of threatened species. We searched for DNA traces of 30 target amphibian species of conservation concern, at different levels of threat, using an environmental DNA metabarcoding approach, together with an extensive sequence reference database to analyse water samples from six montane sites in the Atlantic Coastal Forest and adjacent Cerrado grasslands of Brazil. We successfully detected DNA traces of four declined species (Hylodes ornatus, Hylodes regius, Crossodactylus timbuhy, and Vitreorana eurygnatha); two locally disappeared (Phasmahyla exilis and Phasmahyla guttata); and one species that has not been seen since 1968 (putatively assigned to Megaelosia bocainensis). We confirm the presence of species undetected by traditional methods, underscoring the efficacy of eDNA metabarcoding for biodiversity monitoring at low population densities, especially in megadiverse tropical sites. Our results support the potential application of eDNA in conservation biology, to evaluate persistence and distribution of threatened species in surveyed habitats or sites, and improve accuracy of red lists, especially for species undetected over long periods.

Diversity of the longhorned beetles (Coleoptera: Cerambycidae) from Cuatro Ciénegas Basin, Coahuila, Mexico.

BackgroundCerambycidae is one the most diverse families in the order Coleoptera with more than 37,000 species described in all continents. Cerambicyd beetles have a worldwide distribution from sea level to montane sites. In Mexico, more than 1,600 species have been recorded. Nevertheless, the diversity and distribution of this family in the Mexican deserts is poorly known.New informationA first checklist of Cerambycidae from seven localities of Cuatro Ciénegas Basin is presented. This study is the result of sampling carried out between 2009 to 2013. Some material from other collections is also included. The species list includes four subfamilies, 13 tribes, 32 genera and 37 species, from which 13 are new records for the state of Coahuila and three species represent new records for Mexico. These results highlight the paucity of knowledge of insects in the deserts of Mexico.