Search

Sexual conflict occurs when the fitness interests of the two sexes do not align. Some traits shared by males and females (like mating rate) have sex-specific fitness optima that cannot be achieved simultaneously, and this conflict can favour the evolution of adaptations that benefit one sex but harm the other, like copulatory wounding. Prolonged copulation in damselflies can be seen as a clear example of sexual conflict: while it allows males to guard their partners, preventing them from remating, females cannot feed during copulation and may be more exposed to predators. Ischnura graellsii is one of the species of damselflies in the Coenagrionidae family characterized by females having a conspicuous vulvar spine on the sternum of the eighth abdominal segment, which makes contact with the male seminal vesicle during copulation. To investigate the role of the vulvar spine in sexual conflict, we evaluated whether there is a difference in copulation duration between females with the spine removed and those with an intact spine (control females) and studied the allometry between spine length and body length. We found that the vulvar spine had a significant effect on copulation duration, since males mated on average for 200 min with control females but increased copulation to 227 min with spineless females. The spine was allometric with wing size, but the slope depended on the regression method used. The male seminal vesicle has a depression exactly where the spine is in contact with it during copulation. There was no evidence of physical damage, and consequently, males mated to control and spineless females had similar longevity. We conclude that this spine allows females to reduce mating duration. • Copulation duration is at the core of sexual conflict in damselflies. • A vulvar spine in females acts as a device to shorten copulation duration. • A depression in male's sperm vesicle might be an adaptation to tolerate the spine. [ABSTRACT FROM AUTHOR]

An experimental study was conducted in a natural pond to investigate host plant preference and plasticity in damselfly Onychargia atrocyana. The hypothesis was that this species has a host preference for oviposition and also sufficient plasticity to use other hosts in the absence of the preferred host. After mating, tandems were observed landing on plants in search of suitable oviposition substrates. The majority of landings occurred on Alternanthera philoxeroides, followed by Colocasia esculenta and Commelina diffusa. The frequency of landings on A. philoxeroides and C. esculenta was not significantly different, while landings on C. esculenta and C. diffusa did differ significantly. In the absence of emergent littoral plants, the damselflies exhibited plasticity in host preference and shifted ovipositional substrate by laying eggs on submerged areas of petioles of free-floating Eichhornia crassipes. Females of O. atrocyana exhibited a flexible oviposition strategy, transitioning from a combination of emergent and submerged oviposition to primarily selecting emergent oviposition in most cases. Additionally, they divided oviposition events into multiple phases when required to ensure successful reproduction. E. crassipes supported a higher rate of oviposition compared to other plants. A multiple regression analysis demonstrated that during submerged oviposition water temperature and pH were significant predictors of the duration of submergence. [ABSTRACT FROM AUTHOR]

The high production cost and extremely weak mechanical properties of SiO 2 aerogels have been two major challenges hindering its widespread application. Atmospheric pressure drying (APD) has always been regarded as the optimal process to reduce costs. However, traditional APD is cumbersome, still uses a large amount of expensive raw materials, and is extremely immature. In this study, a novel APD was developed, inspired by the wing changes during adult damselfly process. Inorganic silica source/water was used as the raw material, and CO 2 was used instead of low surface tension solvent to stabilize the aerogel skeleton structure in situ, and ultimately aerogel material was obtained. The thermal conductivity of pure aerogels was as low as 0.0264 W/(m·K), the porosity reached 94.7 %, and the preparation cycle was only 28.5 h. The thermal stability of the skeleton structure and the chemical stability of surface were investigated and showed the hydrophobicity to withstand temperatures up to 400 °C. Aerogel composites feature low thermal conductivity of 0.0283 W/(m·K), and prominent thermal insulation properties over a wide temperature range of 50–300 °C. For traditional APD, this method shortens preparation cycle by 1–6 times. Compared with the commercial aerogel, the cost is reduced by 38.2 %, and the process is simple and environmentally friendly under the premise of ensuring excellent performance. [Display omitted] • A novel atmospheric pressure drying of aerogels preparation inspired by biology. • Stabilization of aerogel structures with CO 2 instead of low surface tension solvents. • The preparation cycle time is shortened by 1–6 times, the cost is reduced by 38.2 %. • Thermal conductivity of 0.0264 W/(m·K) and hydrophobic temperature resistance of 400 °C. • Aerogel composites have outstanding thermal insulation and moisture resistance. [ABSTRACT FROM AUTHOR]

Aquatic insects are key to wetland ecological functioning, and the distribution of amphibious insects such as Odonata jointly depends on environmental conditions in the aquatic and terrestrial settings. Therefore, untangling the relative effects of within‐wetland and landscape composition can help predict the responses of Odonata to environmental alterations in wetlands. Using data from 19 wetlands spanning over the southern Brazilian Pampa (center‐western Rio Grande do Sul state), we assessed the relative importance of water chemistry and land‐cover variables to the richness and composition of larval Odonata assemblages (and suborders Anisoptera and Zygoptera). Anisoptera richness decreased with pH and bare soil area. Water pH and areas of bare soil, mosaic of agricultural land use, and waterbodies land cover were the main drivers of Odonata and Zygoptera composition. Our results indicate that land cover is the main driver of the assemblage structure of larval Odonata, although a complex interplay of mechanisms associated with land conversion and water quality drive the distribution of larval Odonata in freshwater wetlands of the Brazilian Pampa. The major implication of our findings is that land cover modification is the major threat to Odonata distribution in Pampean wetlands, with potential impacts on the trophic structure and functioning of these ecosystems. [ABSTRACT FROM AUTHOR]

Deforestation in the tropics causes shifts in adult odonate community structure, from forests dominated by thermoconforming zygopteran specialists to open areas with higher representations of heliothermic anisopterans. We tested for these shifts in the Maquina and Cuecha rivers in Monteverde, Costa Rica. We compared adult odonate communities in 100 m plots (subdivided into twenty 5 m subplots) located in disturbed, partially open areas with those in 100 m plots located in intact forest and used general linear models to describe how odonate abundance, species richness, species diversity, and the Anisoptera/Zygoptera ratio varied among plots, subplots, habitat type (disturbed/forested), rivers, and as functions of percent canopy cover and light levels. Plots varied in light levels and percent canopy cover, but there were no significant differences in species richness or diversity. Community composition, however, varied across plots and subplots in NMDS and PERMANOVA analyses, largely as a consequence of the preference of Hetaerina cruentata and Paltothemis lineatipes for high light subplots and H. majuscula for low light subplots. NMDS axes were significantly correlated with percent canopy cover and light level in subplots, and the Anisoptera/Zygoptera ratio correlated with NMDS axes at both the plot and subplot scales, indicating that the relative abundance of anisopterans did increase with increasing light and decreasing canopy cover. Differences among plots and habitats can largely be attributed to species-specific differences in habitat selection at a small spatial scale, causing predicted shifts in the Anisoptera/Zygoptera ratio as dominance shifts from endemic forest species to wide-ranging generalists. This is one of the first studies that confirms these patterns for a cloud forest community. [ABSTRACT FROM AUTHOR]

Floodplains are heterogeneous systems adjacent to large rivers periodically flooded by water originating from the river's lateral flow. During floods, the water flows into the surrounding channels, ponds and lakes, creating an integrated dynamic system characterized by a mosaic of lotic and lentic habitats and by the exchange of nutrients and inhabiting organisms between the main river and its floodplain. This study included a total of 14 sampling sites in a floodplain of the Danube River, designated as a Ramsar site. Seven study sites were in near natural condition, while seven others were separated from the Danube floodplain by an embankment and thus were anthropogenically disturbed (e.g. by hydro–morphological alterations and pollution from agricultural fields). Odonata nymphs were sampled over a two–year period in each season using a benthos hand net. A total of 20 Odonata species were recorded. Some of the documented species are of national and/or international conservation concern, which confirms the conservation value of the habitats studied. Species richness, abundance, taxonomic and functional diversity of Odonata were significantly higher at the anthropogenically disturbed sites than at the near natural sites within the studied floodplain area and correlated positively with macrophyte assemblage metrics (species richness, abundance, diversity). The macrophyte assemblage metrics, water transparency, copper and nitrate concentrations and oxygen saturation in the water were key environmental factors shaping Odonata assemblages in the studied floodplain. As Odonata are used as bioindicators of freshwater status worldwide, the presented results could be used in the protection of endangered wetland ecosystems and their biota. The importance of aquatic macrophytes for the conservation of the local Odonata diversity should be considered in the management of anthropogenically disturbed habitats in protected areas. [ABSTRACT FROM AUTHOR]

Age is a critical intrinsic factor that influences the probability of survival of organisms on Earth. In many animals, the lifestyles and habitat occupancy of males and females are so different that the effect of age could be sex-dependent. To reveal such patterns in wild animal populations, we here use a natural population of the Mediterranean demoiselle Calopteryx haemorrhoidalis Vander Linden (Calopterygidae: Zygoptera) in Northeast Algeria to analyze the influence of age and sex on survival probability using daily capture–mark–recapture. We used stepwise model selection on Cormack–Jolly–Seber models that explain recapture and survival probability, including age and sex as covariates. We marked a total of 214 adults throughout the study period (41 days). The sex ratio did not deviate from unity. Recapture probability depended on sex and time, with a slightly higher recapture probability in males (0.30 [95% CI: 0.27–0.35]) than females (0.26 [0.22–0.30]). The survival probability was slightly higher in females (0.89 [0.86–0.91]) than males (0.86 [0.82–0.88]). The best model for the survival probability included an additive effect of sex and age, indicating that the survival probability of both sexes declined with age. Interestingly, the lifespan of some individuals reached 119–130 days, which is surprisingly long compared to other temperate damselflies. [ABSTRACT FROM AUTHOR]

Aquatic ecosystems are among the most affected by anthropogenic impacts, and the rapid detection and measurement of these impacts are of great importance for the maintenance of such environments. The order of aquatic insects Odonata has emerged as an important bioindicator of environmental quality due to its sensitivity to environmental changes and its ecophysiological requirements, which make them closely associated with habitat conditions. The aim of this study was to test whether the Zygoptera/Anisoptera ratio can be used as an effective tool to assess anthropogenic changes in Cerrado streams. Our hypothesis is that the proportion of Zygoptera/Anisoptera is an efficient tool for measuring environmental alterations in Cerrado streams, with a positive relationship between habitat integrity and the proportion of Zygoptera and an inverse relationship with the proportion of Anisoptera. Adults were collected in 44 streams of the Cerrado Biome in the eastern Maranhão state. The Habitat Integrity Index (HII) was used to verify the environmental gradient. Our hypothesis was corroborated, with a positive relationship between the richness and abundance of Zygoptera and HII, while an inverse relationship was observed for Anisoptera. According to our results, streams exhibiting a Zygoptera abundance of 68% or higher and richness of 58% or higher can be classified as preserved, while those showing an Anisoptera abundance and richness surpassing 31% and 41%, respectively, may be deemed altered. The patterns detected in the Cerrado were similar to those found in studies of the Amazon Biome and the Atlantic Forest, confirming the effectiveness of this method even for naturally open environments, such as the Cerrado. We conclude, therefore, that this method can be used as a tool to generate rapid results in monitoring studies, with low cost and easy application, enabling the development of mitigation, control, and conservation measures for extremely threatened environments such as those found in the Cerrado Biome. [ABSTRACT FROM AUTHOR]

The Brazilian Cerrado is a biodiversity hotspot that has suffered significant vegetation loss in the states that make up the so-called MATOPIBA region in recent years an area currently experiencing soybean cultivation expansion in Brazil. This expansion can change the environmental conditions of freshwater streams, as they receive the impacts of activities occurring in their drainage basin. In this study, we assessed how anthropogenic activities impact the conservation status and environmental heterogeneity of streams and how these modifications affect the proportion between abundance and species richness among the suborders of Odonata (Anisoptera and Zygoptera). We also assessed whether conserved streams had a greater number of specialist species when compared to altered streams. To assess these objectives, we collected data from 24 streams within matrices presenting a gradient in their integrity and vegetation cover conditions. Altered areas showed a tendency higher to heterogeneity compared to preserved streams. As expected, we observed that the proportion of abundance and species richness of Zygoptera was higher in preserved streams, while for Anisoptera, it was higher in altered streams. Despite altered sites having higher environmental heterogeneity, we failed to register of a greater number of specialist species in these areas. This implies that the presence of riparian forests is essential for maintaining habitat integrity supporting the maintenance of species that are more sensitive to changes in environmental gradients. Implications for insect conservation: We underscore the significance of permanent protection areas in maintaining the habitat integrity of streams and preserving the diversity of Odonata species, particularly for Zygoptera. [ABSTRACT FROM AUTHOR]

Understanding the distribution patterns of biodiversity is a pivotal challenge in ecology, exacerbated by the escalating frequency of anthropogenic events with severe consequences. This urgency underscores the need for comprehensive investigations, as exemplified by our study, which focuses on evaluating the effects of environmental and spatial variables on Odonata distribution across a gradient of vegetation cover in the eastern Amazonia landscape. In our investigation, we aimed to test the hypothesis that the distribution pattern of species in the suborder Zygoptera is significantly different from that of species in the suborder Anisoptera, considering that the environment is a more important factor for Zygoptera. Sampling was conducted across 27 streams within a landscape altered by various human activities, resulting in changes to riparian forests, sediment influx, and bank destabilization. Environmental alterations were quantified using the Habitat Integrity Index (HII) in conjunction with water's physical-chemical variables. We register 29 Odonata species/morphospecies, reflecting a significant biodiversity. Our hypothesis regarding the differing distribution patterns of species from the Odonata suborders Anisoptera and Zygoptera due to their ecophysiological distinctions was confirmed. This underscores that environmental and spatial factors serve as the primary determinants shaping the structure of Zygoptera suborder assemblages, given that the studied streams harbored environments that greatly impede the dispersal of species within this suborder. This study contributes valuable insights into the interplay between environmental changes induced by land use alterations and the resulting impacts on Odonata biodiversity in the Amazonian landscape. [ABSTRACT FROM AUTHOR]

Mitogenome data of Odonata is accumulating and widely used in phylogenetic analysis. However, noncoding regions, especially control region, were usually omitted from the phylogenetic reconstruction. In an effort to uncover the phylogenetic insights offered by the control region, we have amassed 65 Odonata mitogenomes and conducted an examination of their control regions. Our analysis discovered that species belonging to Anisoptera and Anisozygoptera exhibited a stem-loop structure, which was formed by a conserved polyC-polyG stretch located near the rrns gene (encoding 12S rRNA). Conversely, the polyC-polyG region was not a conserved fragment in Zygoptera. The length and number of repetitions within the control region were identified as the primary determinants of its overall length. Further, sibling species within Odonata, particularly those in the genus Euphaea, displayed similar patterns of repetition in their control region. Collectively, our research delineates the structural variations within the control region of Odonata and suggests the potential utility of this region in elucidating phylogenetic relationships among closely related species. [ABSTRACT FROM AUTHOR]

Aim: Insects are one of the least studied taxa, with most species lacking basic ecological and biogeographical information. This problem is particularly acute in the tropics, where low sampling effort hampers accurate estimates of species richness at scale and potentially confounds efforts to identify the drivers of biogeographical gradients. Here, we evaluate the quality of the data on the distribution and diversity of odonate species in the Neotropics, while also examining the influence of sampling completeness on climate–richness relationships using a comprehensive database of odonates. Location: The Neotropics. Taxon: Odonata. Methods: Using 56,535 records collected from 1970 to 2021, we assess whether climate–species richness models vary under different scenarios of survey completeness. Results: Our survey compilation revealed that most Neotropical diversity of Odonata likely remains unknown. Only 1% of the one‐degree cells covering the Neotropics held reliable information on odonate species richness, with particularly severe gaps in the Caribbean, Central America, northeastern Brazil and northern Chile. Temperature, precipitation and potential evapotranspiration exert consistent effects on Odonata richness across the entire Neotropics, regardless the level of survey completeness. Whereas seasonality‐related variables are less important predictors of species richness at the biogeographical scale. Main Conclusions: By highlighting areas where inventories are more reliable and identifying regions that require increased data collection efforts and mobilization, our assessment offers a roadmap for improving the reliability of odonate inventories in the Neotropics. Furthermore, our findings underscore the importance of accounting for varying levels of survey completeness in macroecological models to reveal robust climate–species richness relationships. Simultaneously, they highlight strong climatic predictors of species richness, irrespective of survey effort intensity. These predictors provide a solid foundation for modelling and predicting odonate species richness in the Neotropics. [ABSTRACT FROM AUTHOR]

The aerodynamic effects of wing corrugation on insect flight have received widespread attention. However, there has hardly been any specific focus on dynamic changes to corrugation angle in the models. The flexible vein joints containing resilin in the wings of dragonflies and damselflies enable the longitudinal veins to rotate and thereby change the corrugation angles throughout flapping cycles. Therefore, a two-dimensional corrugated airfoil with time-varying corrugation angles is proposed and the aerodynamic performance is evaluated in terms of aerodynamic force, power and efficiency. The results indicate that the airfoil with time-varying corrugations outperforms the rigid one in terms of enhancing thrust and reducing power consumption. The aerodynamic performance of time-varying corrugated airfoils is optimal when the angle varies in a specific range, and an excessively large angle variation may have negative effects. In addition, excessive height or a negative leading edge of the corrugation can lead to a reduction in the thrust. A design concept for the 2D airfoil with time-varying corrugations is provided and the findings are of significance for enhancing the aerodynamic performance of biomimetic flexible flapping-wing vehicles. [ABSTRACT FROM AUTHOR]

The odonates community from Cuetzalan and surroundings was studied through direct collections of adults in the years 2007 and 2009. Seventy-two species included in 37 genera and 11 families of the suborders Zygoptera and Anisoptera, were found, of which 19 species are new records for Puebla State. The collections efficiency was evaluated with three non-parametric estimators, reaching percentages of 82-98%. Phylogenetic diversity was calculated and compared to other two areas with cloud forest cover in the Northern Mountain Range in Puebla state and Hidalgo state, resulting more diverse that of Cuetzalan. An illustrated key to adult odonate species is provided. [ABSTRACT FROM AUTHOR]

Dragonflies and damselflies are bioindicator species belonging to the class Insecta. The research was conducted in the Karnali River basin from April to early October 2022 to contribute and update the Odonata checklist of Nepal including documenting regional new species. From the odonatological survey, four species viz., Aristocypha spuria Selys, 1879, Pseudocopera ciliata (Selys, 1863), Aciagrion occidentale Laidlaw, 1919 and Zyxomma petiolatum Rambur, 1842 were recorded for the first time from Nepal. Besides these, Copera marginipes (Rambur, 1842), Copera vittata (Selys, 1863), Prodasineura autumnalis (Fraser, 1922), Agriocnemis clauseni Fraser, 1992, Ceriagrion cerinorubellum (Brauer, 1865), Cephalaeschna viridifrons (Fraser, 1923), Gynacantha incisura Fraser, 1935, Gynacanthaeschna sikkima (Karsch, 1891), Lamelligomphus risi (Fraser, 1922), Scalmogomphus bistrigatus (Hagen in Selys, 1854), Rhodothemis rufa (Rambur, 1842), Tetrathemis platyptera Selys, 1868 and Urothemis signata signata (Rambur, 1862) were newly recorded for western region of Nepal. [ABSTRACT FROM AUTHOR]

Niche and dispersal‐based processes govern freshwater communities, such as aquatic insects, shaping their distribution and establishment in the environment. So, we aimed to address the relative influence of niche and dispersal‐based processes on Odonata diversity in Amazonian freshwater systems, and the influence of species dispersal functional traits on their longitudinal and latitudinal ranges. We used the Dispersal‐Niche Continuum Index (DNCI) to test (i) regions more distant would present a prevalence of dispersal‐based processes, and (ii) different patterns would come from the two Odonata suborders; and by applying generalised linear models, we tested (iii) dispersal‐related functional traits from the suborders would influence latitudinal and longitudinal midpoints of the species. We found that more distant regions had lower values of pairwise Dispersal–Niche Continuum, mainly for Zygoptera, corroborating our first hypothesis. Moreover, Zygoptera also presented the lowest absolute values of Dispersal–Niche Continuum and Anisoptera presented a joint influence of niche and dispersal‐based processes, agreeing with our second hypothesis. Only Zygoptera presented a significant association between dispersal functional traits and longitudinal midpoints, corroborating our third hypothesis. Our results indicated a prevalence of dispersal‐related processes for Zygoptera, which can be explained by massive geographical barriers, such as the rivers, and their narrow physiological and ecological tolerance. Moreover, dispersal‐related traits demonstrated significant influence on longitudinal midpoints of Zygoptera, a scenario that the presence of the rivers may explain. A better understanding of the prevalent predictors of the species and how their dispersal ability governs their distribution has conservational implications. [ABSTRACT FROM AUTHOR]

Scarcity of morphological data limits the potential of functional ecology approaches, which rely on traits to elucidate ecological processes. Dragonflies and damselflies (Odonata) are a frequently used ecological model for which, however, only limited morphological data is available. Here, it is presented a field sampling protocol to collect ecologically relevant yet largely unavailable morphological traits of Odonata. The protocol enables the straightforward collection of traits from living individuals directly in the field. Those traits include body mass, wing area and wing loading as well as thorax width, hindwing length and body length. Furthermore, the protocol allows for posterior wing morphometric analyses. The protocol proved to be robust and universally applicable based on testing on roughly half (76) of all European odonate species. The use of this protocol can increase our understanding of odonatan morphology at interspecific and intraspecific levels and assist in developing mechanistic understanding of their ecology. [ABSTRACT FROM AUTHOR]

Odonates are prominent freshwater insects and play a crucial role in ecosystem functioning as biological indicator of environmental quality. The expansion of urban areas in combination with climate change places great pressure on species found in freshwater habitats. Odonata are iconic freshwater organisms due to their large body sizes and striking coloration. Odonata are hemimetabolous insects, the aquatic larva or nymph hatches from an egg, develops instars before leaving the water and emerging as the winged imago. Thermal tolerance affects Odonates physiology like life process such as growth rate, immune system and pigment. The study was carried out for 12 months from January 2022 to December 2022 in and around Lohara Lake. The objective of this study is to assess the diversity of Odonata species and the impact of temperature on two Odonates families Libelluidae and Coenagrionidae in Lohara Lake. In the present investigation, total 12 species were identified belonging to 11 genera and 2 families. Anisoptera (dragonflies) dominant over Zygoptera (damselflies). Among Anisoptera, 8 species belong to family Libelluidae and in Zygoptera, 4 species belong to family Coenagrionidae.The minimum and maximum temperature of the site was 16°C and 44°C, respectively. [ABSTRACT FROM AUTHOR]

Aim Location Taxon Methods Results Main Conclusions Species have different distribution patterns across the globe and among biogeographical regions. The Nearctic and Palaearctic regions share lineages because of their parallel biogeographic histories and ecological conditions. As the number of phylogenetic studies increases, there are more insights into past exchange events between these two regions and their effects on the current distribution of diversity. However, several groups have not been tested and an overall generalization is still missing. Here, we analyse the biogeographic history across multiple genera of odonates to elucidate a general process of species exchange, vicariance and species divergence between these two regions.The Holarctic, including the entire Nearctic and the East and West Palaearctic.14 genera of Odonata (Insecta).We reconstructed a time‐calibrated phylogenetic tree for each genus to determine species relationships and divergence time using 3614 COI sequences of 259 species. Biogeographic ancestral range estimation was inferred for each phylogeny using BioGeoBEARS. Preferred habitat (lotic versus lentic) was established for each species.Exchange events were not restricted in time, direction or either lentic habitat or lotic habitat. Most genera crossed between both regions only once, and it was mainly across the Beringia, while three diverse anisopteran genera revealed multiple exchanges. Recent exchanges during the Pleistocene were associated with cold‐dwelling and lentic species.Our finding reveals the absence of a generalizable pattern of species exchange and divergence between the Nearctic and Palaearctic regions; instead, we found lineage‐specific biogeographic patterns. This finding highlights the complexity of drivers and functional traits that shaped current diversity patterns. Moreover, it emphasizes that general conclusions cannot be formulated based on one single clade. [ABSTRACT FROM AUTHOR]

We aim to explore what processes dominate community assembly of dragonflies (Odonata: Anisoptera) and damselflies (Odonata: Zygoptera) by differentiating the environmental and geographical drivers behind compositional turnover of narrow‐ranged versus widespread species. In this way, we further aim to describe patterns of species incidence and compositional turnover to expand upon the body of knowledge related to understanding biodiversity patterns and processes.We explored species turnover of dragonflies and damselflies separately, using zeta diversity to measure compositional turnover among multiple assemblages.Narrow‐ranged and widespread species within each suborder showed similar drivers. Specifically, both narrow‐ranged and widespread dragonflies show rapid turnover with small shifts in annual mean temperature, temperature seasonality and annual precipitation, whereas for damselflies, the major driver for turnover is distance between sites followed by climatic variables. Our results therefore show that odonate turnover is largely driven by climate, although the limited dispersal capabilities of damselflies also influences community assembly.Climate change could cause major changes in composition of odonates, presenting a challenge for conservation planning in Africa as species assemblages that were previously conserved may no longer be protected if their ranges shift outside protected areas. For damselflies, adaptation is a major concern, and with their limited dispersal capabilities and climate sensitivity, they may not be able to migrate effectively in response to changing climate conditions. The underlying assembly processes do not differ considerably for narrow‐ranged and widespread species within each suborder, suggesting that conservation planning tailored to each suborder may be sufficient in Africa. [ABSTRACT FROM AUTHOR]

While most flowering plant species rely on animal pollinators, approximately 10% of angiosperms utilize wind or water for pollination. Moreover, certain species can have mixed pollination system—ambophily—wherein both biotic and abiotic agents contribute to pollen transport. Upon frequent observation of damselflies (Coenagrionidae) perching on Callitriche rimosa Fassetv (Plantaginaceae), an aquatic herb with small flowers protruding above the water's surface, we hypothesized their potential contribution to the pollination of this primarily abiotically pollinated plant. Observations were conducted along the shores of a pond in southern Brazil. Damselflies were seen carrying pollen grains on their legs from C. rimosa leaves, where pollen falls from the anthers and remains exposed. Given damselflies' activity levels during summer, incidental contact with C. rimosa reproductive structures facilitates cross‐pollination. This interaction may facilitate both plants and insects, considering damselflies' dependence on freshwater bodies and use of C. rimosa leaves for perching. Accessory pollen presentation on leaves may convert occasional visitors into pollinators, expanding the pollination niche of C. rimosa. Recognizing lesser‐known pollinators like damselflies is crucial for understanding plant reproduction in diverse ecosystems. This study investigates the role of damselflies in pollinating Callitriche rimosa Fasset, traditionally considered to be abiotically pollinated. Through field observations in southern Brazil, we documented damselflies interacting with C. rimosa, potentially contributing to its pollination. Our findings shed light on the overlooked role of damselflies as pollinators in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

We present a checklist of Odonata (Insecta) species occurring in streams in the municipality of Araquari, northeastern state of Santa Catarina (SC), southern Brazil. Five stream reaches were surveyed bi-annually from March 2016 to March 2018. Overall, we recorded 18 taxa (16 species) from 12 genera and four families. Coenagrionidae and Libellulidae were the most species-rich families (seven species each; 43% of the total number of species recorded each). Idioneura ancilla Selys, 1860, Telagrion longum Selys, 1876 (Coenagrionidae) and Erythrodiplax umbrata (Linnaeus, 1758) (Libellulidae) are recorded for the first time in the state of Santa Catarina. Species occurrence patterns were remarkably seasonal in the studied streams, with 70% of the species recorded in the summer only, and only 25% of the species occurring in both seasons at the same stream. Our findings revealed odonate communities with marked space-time interactions in species occurrence and contribute to understand odonate biology in subtropical streams in a human-dominated landscape, and also contribute to improve the knowledge on odonate distribution in South America. Keywords: Anisoptera; aquatic insects; Atlantic Forest; streams; Zygoptera. [ABSTRACT FROM AUTHOR]

Understanding species diversity and distribution cannot be overstated in the development of effective management and biological conservation strategies. Our goal was to address the knowledge gap regarding dragonfly diversity in the northeastern Atlantic Forest, specifically in the Serra of Itabaiana National Park in the state of Sergipe, Brazil. During our study, we recorded 40 species and 969 Odonata individuals across six families and 25 genera. This study contributes 27 new occurrence records of Odonata species in Sergipe, Brazil, highlighting the significance of preserving and protecting the habitats of this region. Our findings provide valuable information on the distribution of dragonfly species in the state of Sergipe and the Northeast region. [ABSTRACT FROM AUTHOR]

Dragonflies and damselflies are excellent bioindicators of the quality of both aquatic and terrestrial ecosystems. In our study, we assessed the usefulness of metric and meristic morphological traits as environmentally friendly and cost‐effective indicators of the integrative ecological quality of watercourses. Our study species of choice was the damselfly banded demoiselle, Calopteryx splendens (Harris) (Odonata: Calopterygidae). Adult C. splendens specimens were collected at three study sites along the trophic gradient of the Tisza River in Hungary and Ukraine. Body and abdomen length, head width, and distances between wing landmarks were assessed as metric traits, and the number of wing cells as meristic traits. The concentration of chlorophyll‐a was used to classify the three study sites into having a low, intermediate, and high trophic condition based on earlier studies. Significant differences were found along the trophic gradient based on the measured metric and meristic traits. Especially, insects from the site with the highest trophic condition had the largest body length, head width, and distances between wing landmarks, as well as the highest number of cells in the fore wings. There were also differences between males and females, but we did not find differences in fluctuating asymmetry (FA), i.e., differences between the left and the right wings. These results indicated that the morphological traits of adult banded demoiselles could be indicative of the environmental quality of a watercourse. [ABSTRACT FROM AUTHOR]

Our understanding of how biotic interactions influence animal community assembly is largely restricted to local systems due to the difficulty of obtaining ecologically meaningful assemblage data across large spatial extents. Here, we used thousands of spatio‐phenologically high‐resolution assemblages across three distinct European regions together with a functional diversity approach to understand community assembly of dragonflies and damselflies (Odonata), an insect group characterized by a pronounced competitive reproductive biology. We found that adult dragonfly, but not damselfly, assemblages were consistently composed of species morphologically more different than expected by chance based on the traits that enhance their interspecific reproductive encounters. These results provide consistent evidence for the role of competition in the assembly of animal communities, which we interpret is most likely caused by the territorial reproductive biology of dragonflies. Support for competition varied both spatially and seasonally following theoretical expectations, as it was strongest in locations and seasonal moments with low thermal stress (i.e. warm conditions) and high niche packing. Our study illustrates how spatio‐temporal diversity patterns arise from variation in assembly processes. [ABSTRACT FROM AUTHOR]

Aim: Species are largely thought to maintain broadly static niches over time, an assumption underpinning much theoretical ecology including the implementation of ecological models to project species' current and future distributions. Here, we assess niche conservatism in odonates in Great Britain over the past six decades by simultaneously quantifying changes in species geographic distribution and evaluating temporal trends in species realised climatic niche. Location: Great Britain. Methods: Distributional changes were assessed by calculating changes in species distribution centres and deriving occupancy trends. Changes in climatic niches were assessed using a principal component analysis to quantify niche overlap, using information on both climate averages and extremes. Results: We show that dragonflies and damselflies displayed distinct responses to changing climatic conditions. Dragonflies shifting to higher latitudes maintained, on average, greater consistency in their climatic niches, providing evidence for climate tracking. Greater climate niche flexibility and increased occupancy over time, on the other hand, were more common in damselflies. Main Conclusions: We unveil evidence for climatic niche divergence in damselflies on a national scale, casting doubt on the relevance of species distribution models for predicting the impacts of climate change on this, and potentially other, groups of species. More broadly, our results call for more multi‐species temporal comparisons of spatial distributions and climate niches during recent periods of changes in climatic conditions to improve our ability to contrast species' vulnerability risk to the ongoing climate crisis. [ABSTRACT FROM AUTHOR]

Interference competition can drive species apart in habitat use through competitive displacement in ecological time and agonistic character displacement (ACD) over evolutionary time. As predicted by ACD theory, sympatric species of rubyspot damselflies (Hetaerina spp.) that respond more aggressively to each other in staged encounters differ more in microhabitat use. However, the same pattern could arise from competitive displacement if dominant species actively exclude subordinate species from preferred microhabitats. The degree to which habitat partitioning is caused by competitive displacement can be assessed with removal experiments. We carried out removal experiments with three species pairs of rubyspot damselflies. With competitive displacement, removing dominant species should allow subordinate species to shift into the dominant species' microhabitat. Instead, we found that species-specific microhabitat use persisted after the experimental removals. Thus, the previously documented association between heterospecific aggression and microhabitat partitioning in this genus is most likely a product of divergence in habitat preferences caused by interference competition in the evolutionary past. [ABSTRACT FROM AUTHOR]

Mark Release Re-capture studies used in the evolution of animals and animal ecology. While it is probably to be used in some animals, it is considerably more challenging in small fast-moving invertebrate species, especially insects. In these groups, low rates of recapture can bias estimates of demographic parameters, thereby handicapping effective analysis and management of wild animal populations. The author used the markrecapture method and daily movement of Ischnura elegans. The retention rate probability was different between males and females of Ischnura elegans. 969 individuals of Ischnura elegans (710 males and 259 females) were marked, recaptured and measured over the course of the study, of which 409 individuals (42.2%) 357 males and 52 females, were recaptured. The daily movement of Ischnura elegans shows, that 401 individuals were marked and 223 individuals were moved throughout the station or among stations. [ABSTRACT FROM AUTHOR]

Simple Summary: Aquatic habitats in urban areas are often important for conservation of local biodiversity. Although Odonata are widely used as ecological indicators of freshwater habitat integrity and health, our understanding and knowledge of their ecological requirements in urban landscapes is not yet complete. Therefore, the taxonomic and functional diversity of Odonata assemblages was analyzed in a semi-natural wetland in the Croatian capital in the summers of 2020 and 2023. The two main habitat types, anthropogenically disturbed and natural oxbow lakes, mostly had comparable assemblage metrics. However, we found significant differences in relation to the time scale, where most metrics were lower in 2023, indicating the negative impact of extreme climate events (including droughts) that occurred in this region after 2020. As even some species of conservation concern were detected, our results indicate that semi-natural urban wetlands, especially natural oxbow lakes, have great potential to function as good habitats for Odonata. As the human population in urban areas is continuously growing, urbanization is one of the greatest threats to biodiversity. To mitigate the negative effects, the inclusion of blue zones (aquatic habitats) in modern urban development practices is strongly recommended, as they could be beneficial for the local biodiversity conservation. Odonata are a flagship group and are widely used in freshwater conservation as ecological indicators of habitat integrity and health. However, our understanding of their ecological requirements in urban landscapes is not yet complete. Therefore, we analyzed the taxonomic and functional diversity of Odonata in a semi-natural wetland in the Croatian capital. This study was conducted in the summers of 2020 and 2023. Most taxonomic and functional assemblage metrics were comparable between the two main habitat types, anthropogenically disturbed and natural oxbow lakes. However, significant differences were found in relation to the time scale, where most metrics were lower in 2023, indicating the negative impact of extreme climate events (including droughts) that occurred in this region after 2020. With 19 species recorded, our results indicate that semi-natural urban wetlands, especially natural oxbow lakes, have great potential to function as good habitats for Odonata, where even some species of conservation concern were detected. When developing landscape management plans in urban areas, it is essential to consider the importance of habitat heterogeneity in terms of good structure of aquatic macrophytes (presence of submerged, emergent and floating vegetation), which would ensure the most suitable habitat conditions for local Odonata species. [ABSTRACT FROM AUTHOR]

The processes responsible for the formation of Earth's most conspicuous diversity pattern, the latitudinal diversity gradient (LDG), remain unexplored for many clades in the Tree of Life. Here, we present a densely sampled and dated molecular phylogeny for the most speciose clade of damselflies worldwide (Odonata: Coenagrionoidea) and investigate the role of time, macroevolutionary processes, and biome-shift dynamics in shaping the LDG in this ancient insect superfamily. We used process-based biogeographic models to jointly infer ancestral ranges and speciation times and to characterize within-biome dispersal and biome-shift dynamics across the cosmopolitan distribution of Coenagrionoidea. We also investigated temporal and biome-dependent variation in diversification rates. Our results uncover a tropical origin of pond damselflies and featherlegs ~105 Ma, while highlighting the uncertainty of ancestral ranges within the tropics in deep time. Even though diversification rates have declined since the origin of this clade, global climate change and biome-shifts have slowly increased diversity in warm- and cold-temperate areas, where lineage turnover rates have been relatively higher. This study underscores the importance of biogeographic origin and time to diversify as important drivers of the LDG in pond damselflies and their relatives, while diversification dynamics have instead resulted in the formation of ephemeral species in temperate regions. Biome-shifts, although limited by tropical niche conservatism, have been the main factor reducing the steepness of the LDG in the last 30 Myr. With ongoing climate change and increasing northward range expansions of many damselfly taxa, the LDG may become less pronounced. Our results support recent calls to unify biogeographic and macroevolutionary approaches to improve our understanding of how latitudinal diversity gradients are formed and why they vary across time and among taxa. [ABSTRACT FROM AUTHOR]

The evaluation of environmental and spatial influence in freshwater systems is crucial for the conservation of aquatic diversity. So, we evaluated communities of Odonata in streams inside and outside sustainable use areas in the Brazilian western Amazon. We predicted that these streams would differ regarding habitat integrity and species α and β diversity. We also predict that environmental and spatial variables will be important for both suborders, but with more substantial effects on Zygoptera species, considering their nature of forest-specialist. The study was conducted in 35 streams, 19 inside and 16 outside sustainable use areas. The streams outside presented high species richness, abundance, and number of exclusive forest-specialist species from Zygoptera and higher scores of habitat integrity. In contrast, one sustainable use area presented the lowest values of these metrics. Besides, we found that environmental and spatial variables were significantly associated to Zygoptera species composition, but not with Anisoptera, which can be explained by their cosmopolitan nature. Our results indicated that an interplay between environmental and spatial processes determines the structure of the metacommunities of Zygoptera. The less effective dispersal rates and narrow ecological tolerance of Zygoptera species make them more influenced by local conditions and dispersal limitation, and more sensible to habitat modifications. We highlight the importance of improving the local management of the sustainable use areas by environmental agencies, mainly on areas that are losing their capacity to maintain the aquatic fauna, and implementation of social policies toward traditional people. [ABSTRACT FROM AUTHOR]

The odonate diversity of the Silent Valley National Park (SVNP) in the Western Ghats (WG) of Kerala state, in southern India, is discussed. A total of 111 species of odonates (41 Zygoptera and 70 Anisoptera) including 29 endemics were recorded for the SVNP region, out of the 181 species (14 families, 87 genera with 68 WG endemics). SVNP harbours 53.37 per cent of WG and 61.34 per cent of the odonate diversity of Kerala. In addition, this includes 42.64 percent endemic odonates of Kerala and 35.80 percent of WG. With respect to IUCN Red List status, there were two vulnerable, three near threatened, 84 least concerned, 17 data deficient, and five species whose status was not assessed. Family Libellulidae (40 species) dominated the diversity, followed by Coenagrionidae and Gomphidae (16 species each). None of the species listed from SVNP is protected under the Indian Wildlife (Protection) Amendment Act, 2022. [ABSTRACT FROM AUTHOR]

Odonata diversity study was carried out from September 2020 to October 2022 in the Mettur Dam, Salem District. Among the total 40 different species, 27 species were in Anisoptera (dragonflies) and 13 species in Zygoptera (damselflies) under five families. Libellulidae was the largest family recorded (16 species), followed by Coenagrionidae (11), Aeshnidae (2), Lestidae (2) and Gomphidae (1). A migratory species, Pantala flavescens, was the most dominant in numbers throughout the year. Maximum number of individuals was found during September 2020 to September 2021. Odonata diversity was higher in the first season of 2021 than in next second season. Both dragonflies and damselflies mainly used wetlands of the dam ecosystem and agricultural fields rather than shrubland. [ABSTRACT FROM AUTHOR]

Abstract Scarcity of morphological data limits the potential of functional ecology approaches, which rely on traits to elucidate ecological processes. Dragonflies and damselflies (Odonata) are a frequently used ecological model for which, however, only limited morphological data is available. Here, it is presented a field sampling protocol to collect ecologically relevant yet largely unavailable morphological traits of Odonata. The protocol enables the straightforward collection of traits from living individuals directly in the field. Those traits include body mass, wing area and wing loading as well as thorax width, hindwing length and body length. Furthermore, the protocol allows for posterior wing morphometric analyses. The protocol proved to be robust and universally applicable based on testing on roughly half (76) of all European odonate species. The use of this protocol can increase our understanding of odonatan morphology at interspecific and intraspecific levels and assist in developing mechanistic understanding of their ecology.

A preliminary study of the odonate fauna of Wayanad Wildlife Sanctuary, Kerala, southern India was carried out from August 2020 to November 2020. Ponds, streams, and swamps in the sanctuary were sampled using Visual Encounter Surveys (VES). A total of 85 species (49 dragonflies and 36 damselflies) from 11 families were recorded, out of which 14 species are endemic to the Western Ghats. Orthetrum pruinosum was found to be the most common species in the sanctuary. Indolestes pulcherrimus, an endemic species with no recent records, is being reported for the first time with photographs from the wild. The highest number of species was recorded in the ponds (56 species), followed by streams (46 species) and swamps (33 species). However, the number of endemic species was highest in the streams (8 species), followed by swamps (3 species) and ponds (2 species). [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal Diversity that focuses on the diversity, ecology, and evolution of dragonflies and damselflies. The articles in this special issue cover a range of topics, including the impact of climate change on dragonfly populations, taxonomic revisions of specific species, and the diversity of dragonflies and damselflies in different regions. The articles provide valuable insights into the taxonomy, distribution, and conservation of these insects. Additionally, the special issue includes a bibliometric analysis of global Odonata research, which identifies research trends and gaps in the field. [Extracted from the article]

One area of animal behaviour of growing interest is related to the behavioural traits that favour species' survival in rapidly changing environments (e.g. cities). In this regard, one animal group that is resilient to urbanization is that of odonate insects. These animals are formidable generalist predators that exhibit large behavioural flexibility. Here we tested whether adult odonate communities show differences in behavioural traits associated with reproduction, foraging and thermoregulation in relation to an urbanization gradient. Our results indicate that individuals were more efficient at capturing prey in more urbanized places. More effective predation in cities may occur because of changes in the environment, changes in odonate behaviour or modifications in prey communities whose characteristics influence the success rate of odonates during hunting. • Behavioural traits are adaptive tools for responding to rapid environmental change. • Odonata communities appear to be resilient to urbanization. • We evaluated effects of urbanization on odonate behaviour in the Brazilian Amazon. • Odonates were less likely to fail during prey capture in more urbanized sites. • Foraging efficiency may be one strategy to deal with urbanized environments. [ABSTRACT FROM AUTHOR]

The evolution of reproductive barriers, that is, the speciation process, implies the limitation of gene flow between populations. Different patterns of genomic differentiation throughout the speciation continuum may provide insights into the causal evolutionary forces of species divergence. In this study, we analysed a cryptic species complex of the genus Hetaerina (Odonata). This complex includes H. americana and H. calverti; however, in H. americana two highly differentiated genetic groups have been previously detected, which, we hypothesize, may correspond to different species with low morphological variation. We obtained single nucleotide polymorphism (SNP) data for 90 individuals belonging to the different taxa in the complex and carried out differentiation tests to identify genetic isolation. The results from STRUCTURE and discriminant analysis of principal components (DAPC), based on almost 5000 SNPs, confirmed the presence of three highly differentiated taxa. Also, we found FST values above 0.5 in pairwise comparisons, which indicates a considerable degree of genetic isolation among the suggested species. We also found low climatic niche overlap among all taxa, suggesting that each group occurs at specific conditions of temperature, precipitation and elevation. We propose that H. americana comprises two cryptic species, which may be reproductively isolated by ecological barriers related to niche divergence, since the morphological variation is minimal and, therefore, mechanical barriers are probably less effective compared to other related species such as H. calverti. [ABSTRACT FROM AUTHOR]

We evaluated whether ecological thresholds could be detected along gradients of disturbances by using larval Odonata genera. Morphological, physiological, and behavioral differences between Odonata suborders may be reflected in different thresholds to anthropogenic disturbance. Therefore, we hypothesized that larval Zygoptera genera would have narrower ecological thresholds in response to increased levels of stream disturbance and would be considered sensitive to anthropogenic disturbances, and the opposite for larval Anisoptera genera, which would have wider ecological thresholds and would be considered tolerant to anthropogenic disturbances. We assessed 30 larval Odonata genera collected from 186 headwater stream sites in the Neotropical Savanna. Threshold Indicator Taxa Analysis detected ecological thresholds in seven Odonata genera (Argia, Brechmorhoga, Cacoides, Gomphoides, Phyllocycla, Progomphus and Hetaerina) revealing them as robust bioindicators (purity and reliability ≥ 0.85). Most Zygoptera were associated with less-disturbed sites and most Anisoptera were associated with more-disturbed sites, but not all genera corresponded to this pattern. Therefore, we recommend using Odonata larvae at the genus-level, versus the suborder level, for constructing improved biomonitoring tools and obtaining more accurate impact assessments of neotropical stream sites. [ABSTRACT FROM AUTHOR]

Odonate assemblages were surveyed in seven sites within the context of the EU LIFE project GREENCHANGE that aims to preserve biodiversity and to enhance the ecological value of the agro-ecosystems of Agro Pontino (Latina, Central Italy) through interventions of ecological restoration. In total 16 species were recorded during the ante-operam surveys in 2019, which represent 28% of the Odonate fauna of the Lazio Region. None of them has a significant conservation interest, however Coenagrion castellani, an endemic Italian species, was observed in a small rivulet near the Pantanello site during an additional field survey. The application of OHI (Odonate Habitat Index) and ORI (Odonate River Index) allowed a detailed characterization of the dragonfly assemblages that are mainly dominated by eurytopic and euryecious species typical of standing waters. The assemblages of Pantanello and Fosso Epitaffio are notable exceptions thanks to the presence of sensitive lentic and lotic species. The main pressures affecting Odonate assemblages identified in the study area are the alterations of aquatic and riparian vegetation, the hydromorphological degradation of running waters, limited water quality and the presence of the invasive crayfish Procambarus clarkii. [ABSTRACT FROM AUTHOR]

Smoky rubyspot damselflies (Hetaerina titia Drury, 1773) are one of the most commonly encountered odonates along streams and rivers on both slopes of Central America and the Atlantic drainages in the United States and southern Canada. Owing to their highly variable wing pigmentation, they have become a model system for studying sexual selection and interspecific behavioral interference. Here, we sequence and assemble the genome of a female smoky rubyspot. Of the primary assembly (i.e. the principle pseudohaplotype), 98.8% is made up of 12 chromosomal pseudomolecules (2N = 22A + X). There are 75 scaffolds in total, an N50 of 120 Mb, a contig-N50 of 0.64 Mb, and a high arthropod BUSCO score [C: 97.6% (S: 97.3%, D: 0.3%), F: 0.8%, M: 1.6%]. We then compare our assembly to that of the blue-tailed damselfly genome (Ischnura elegans), the most complete damselfly assembly to date, and a recently published assembly for an American rubyspot damselfly (Hetaerina americana). Collectively, these resources make Hetaerina a genome-enabled genus for further studies of the ecological and evolutionary forces shaping biological diversity. [ABSTRACT FROM AUTHOR]

Understanding species distributions and predicting future range shifts requires considering all relevant abiotic factors and biotic interactions. Resource competition has received the most attention, but reproductive interference is another widespread biotic interaction that could influence species ranges. Rubyspot damselflies (Hetaerina spp.) exhibit a biogeographic pattern consistent with the hypothesis that reproductive interference has limited range expansion. Here, we use ecological niche models to evaluate whether this pattern could have instead been caused by niche differentiation. We found evidence for climatic niche differentiation, but the species that encounters the least reproductive interference has one of the narrowest and most peripheral niches. These findings strengthen the case that reproductive interference has limited range expansion and also provide a counterexample to the idea that release from negative species interactions triggers niche expansion. We propose that release from reproductive interference enables species to expand in range while specializing on the habitats most suitable for breeding. [ABSTRACT FROM AUTHOR]

Urbanization has driven one of the most substantial transformations in water bodies exposing groups such as aquatic insects to new challenging conditions. Some odonate (dragonflies and damselflies) species persist in these transformed environments, but it remains unclear which morphological or behavioral traits allow them to survive. Through a bibliographical review we identified 88 urbanization-tolerant and 87 urbanization-sensitive odonate species worldwide. We searched morphological and behavioral traits and used phylogenetic path analysis for Anisoptera and Zygoptera to test which traits make species more sensitive to urban environments. Our results show that habitat preference was not linked with the sensitivity to urbanization whereas larger species with weak sexual dimorphism stood out as consistently associated with sensitivity to urban environments. For dragonflies, species with yellow to red colorations tend to be less sensitive to urban areas while for damselflies, territorial species tend to be less sensitive to urban areas. We discuss the underlying mechanisms linked to such urban-surviving ability as well as how we can use such information for conservation purposes. [ABSTRACT FROM AUTHOR]

Copyright of Libellula is the property of Gesellschaft Deutschsprachiger Odonatologen e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite being central to the implementation of conservation policies, the usefulness of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species is hampered by the 14% of species classified as data‐deficient (DD) because information to evaluate these species' extinction risk was lacking when they were last assessed or because assessors did not appropriately account for uncertainty. Robust methods are needed to identify which DD species are more likely to be reclassified in one of the data‐sufficient IUCN Red List categories. We devised a reproducible method to help red‐list assessors prioritize reassessment of DD species and tested it with 6887 DD species of mammals, reptiles, amphibians, fishes, and Odonata (dragonflies and damselflies). For each DD species in these groups, we calculated its probability of being classified in a data‐sufficient category if reassessed today from covariates measuring available knowledge (e.g., number of occurrence records or published articles available), knowledge proxies (e.g., remoteness of the range), and species characteristics (e.g., nocturnality); calculated change in such probability since last assessment from the increase in available knowledge (e.g., new occurrence records); and determined whether the species might qualify as threatened based on recent rate of habitat loss determined from global land‐cover maps. We identified 1907 species with a probability of being reassessed in a data‐sufficient category of >0.5; 624 species for which this probability increased by >0.25 since last assessment; and 77 species that could be reassessed as near threatened or threatened based on habitat loss. Combining these 3 elements, our results provided a list of species likely to be data‐sufficient such that the comprehensiveness and representativeness of the IUCN Red List can be improved. [ABSTRACT FROM AUTHOR]

The β-diversity studies reveal diversity patterns at a spatial scale and strengthen the process of regional diversity conservation. The aim of the current study was to understand the pattern of local contribution to β-diversity (LCBD) and species contribution to β-diversity (SCBD) of odonates in the Ganga River. We selected 27 sites along the banks of the Ganga River for the study, with an average distance between sites of 75 km, and recorded 30 species of odonate (species richness between 5 and 24) at these sites. Using β-regression analysis, we examined the impact of species richness and habitat variables on the LCBD. The LCBD was found to be negatively correlated with species richness and influenced by creeping macrophytes, water temperature, dissolved oxygen and salinity. We found that species with high SCBD scores (above 0.05) had intermediate occupancy (between 10 and 16 sites), including 5 species of dragonfly and 5 species of dragonfly, and that the second-degree term the relationship between SCBD and the number of declared locations better stocked with species than in the first degree. Since the SCBD is responsible for identifying species that make the greatest contribution to β-diversity and the LCBD is responsible for identifying sites with particular combinations of species, the combined approach using both should be included for ecological assessments, river biodiversity restoration and maintenance plans. [ABSTRACT FROM AUTHOR]