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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.

The aim of this study was to investigate the effects of oil palm (Elaeis guineensis) plantations on the water quality and physical structure of streams in the Amazon region and on the diversity of adult odonates (Insecta: Odonata). We tested the hypotheses: (1) that streams draining palm oil monocultures have low water quality and physical integrity and (2) that changes in water quality (local variables) and physical structure (landscape variables) of streams affect the abundance and species richness of the Odonata. A total of 22 streams were studied, of which 15 were in drainage areas used for oil palm plantations and seven were in primary forest areas in the eastern Amazon, Pará State, Brazil. To represent environmental conditions, we selected local variables (e.g., temperature, dissolved oxygen, and turbidity) and landscape variables (e.g., vegetation at 50 and 500 m distance from sampling points) known to be important for the Odonata community. Our results showed that oil palm plantations impact both the physical structure of Amazonian streams and Odonata diversity. The analyses revealed that Odonata abundance and species richness were influenced differently by the variables tested, with dissolved oxygen positively related to Odonata abundance and water temperature and turbidity negatively related to Odonata abundance. Changes in the surrounding vegetation were found to affect the physical structure of streams and influence dragonfly communities. Based on these results, we recommend the implementation of integrated approaches that consider local and landscape factors when monitoring aquatic ecosystems. [ABSTRACT FROM AUTHOR]

ABSTRACT Biodiversity monitoring increasingly relies on molecular methods such as eDNA metabarcoding. However, sound applications have so far been only established for a limited number of taxonomic groups. More information on the strengths and weaknesses of eDNA methods, especially for poorly covered groups, is essential for practical applications to achieve the highest possible reliability. We compared amphibian and Odonata data from eDNA metabarcoding and traditional transect walks on N = 56 plots in 38 water bodies distributed over six extraction sites for building materials in Northwest Germany. The traditional amphibian assessment included visual encounters, dip netting and acoustic detection, while Odonata were assessed through exuviae. In total, both methods detected 8 out of 11 amphibian species, while the remaining three species were detected by eDNA only. We did not find differences in amphibian species numbers per plot, but mean detection probabilities were higher with metabarcoding. In contrast, both methods detected 10 out of 29 Odonata species, while the remaining 19 species were detected by exuviae only. Species numbers per plot were higher for exuviae and only 30% of species were detected with metabarcoding. The species identified by eDNA were those with high abundance, and their detection probabilities were similar to transect walks. The results for amphibians show equal suitability and high complementarity of the compared methods. Metabarcoding detected species more efficiently and therefore offers a suitable protocol for biodiversity monitoring. For Odonata, eDNA metabarcoding showed considerable gaps, implying the need for protocol evaluation and improvement in assessment of ecological communities based on eDNA. [ABSTRACT FROM AUTHOR]

Because insects are unable to regulate their body temperatures, they are vulnerable to rising temperatures and habitat disturbances that limit access to optimal microhabitats. This study examines how these factors affect the taxonomic and functional diversity of Odonata insects (Anisoptera and Zygoptera) in a tropical dry landscape. We assessed taxonomic diversity using Hill numbers (0D, 1D, 2D) and functional diversity in preserved and disturbed sites within a tropical dry forest. Functional diversity was measured using the standardised effect size (SES) of functional richness, evenness, divergence and community‐weighted means (CWMs), focusing on traits related to heat tolerance and resource acquisition (body colouration and size). Taxonomic diversity was positively related to high temperatures and vegetation in Anisoptera, with no relation for Zygoptera. The SES of functional richness for Zygoptera was higher in preserved areas, while anisopterans showed no changes. Only Anisoptera showed a negative correlation between functional evenness and maximum temperatures. Functional divergence in both suborders was higher in disturbed areas. In Anisoptera, the CWM of body colour lightness was higher in disturbed sites, but neither environmental factor affected the CWM of body size in either suborder. While disturbance limited trait variability in zygopterans, it favoured species with extreme traits in both suborders. Reduced trait variability in preserved sites may have affected adaptability to future disturbances. Our study highlights that Odonata communities maintain stable taxonomic diversity despite disturbances, but shifts in functional diversity could compromise their resilience and ecological roles. [ABSTRACT FROM AUTHOR]

A study was conducted at Munnar Forest Division Idukki District, Kerala, the southern Western Ghats, to assess the diversity of odonates. Around 44 species of odonates, which include 29 species of Anisoptera (dragonflies) and 15 species of Zygoptera (damselflies). The odonate diversity of Munnar Forest Division accounted for 24.72 % of the odonates in Kerala and 22.45 % of the odonates of the Western Ghats. The study highlights the importance of biodiversity documentation at high altitudes in the Western Ghats. [ABSTRACT FROM AUTHOR]

A number of expeditions to eight freshwater systems within and around protected areas in the southern region of Nigeria were carried out between 2019 and 2022, with a view to re-discovering relict, rare, and poorly known aquatic invertebrate species. A total of 167 species from 10 orders were collected. Four species were recorded for the first time from Nigeria: Chlorocypha luminosa Karsch, 1893 and C. glauca Selys, 1879 (Odonata: Chlorocyphidae), Ephoron savignyi Williamson, 1802 (Ephemeroptera: Polymitarcyidae), and Cylindrostethus quadrivittatus Bergroth, 1916 (Hemiptera: Gerridae). Findings from this study also revealed that the distribution ranges of Elattoneura girardi Legrand, 1980 (Odonata: Platycnemididae) and Eurymetropsiella schoutedeni Poisson, 1950 (Hemiptera: Gerridae) extend to the southeastern region of Nigeria from the southwestern and northeastern regions, respectively. Rare and/or endemic species of Gerridae (Hemiptera) such as Eurymetra pauliani Poisson, 1941, Eurymetropsiella schoutedeni and Eurymetropsis carayoni Poisson, 1948 were also recorded in this study after several decades of paucity of information on their occurrence. The implications of aquatic invertebrate taxonomy and systematics on conservation in West Africa are discussed, and recommendations are provided. [ABSTRACT FROM AUTHOR]

The Jurassic damsel-dragonfly family Paragonophlebiidae was till now monogeneric, with the sole genus Paragonophlebia and the two species P. inexpectata and P. patriciae , from the Middle Jurassic of Central Asia. Here we describe the new genus and species Sinagonophlebia yananensis Nel and Huang, from the Middle Jurassic of China, and we attribute the late Triassic and early Jurassic Diastatommites liassina (Strickland, 1840) from UK to the same family. We restore it in the genus Diastatommites Tillyard, 1925. We also describe the selenothemistid Yananthemis zaoyuanensis Nel and Huang, nov. gen., nov. sp., plus an isophlebiid gen. et sp. indet. from the same outcrop. These three damsel-dragonflies increase our knowledge on the already impressive diversity of the Odonata from the Mesozoic of China. [ABSTRACT FROM AUTHOR]

Aim: Human activities pose many challenges to freshwater biodiversity. Among these, is landscape transformation, such as conversion of natural grassland to plantation forestry, impacting both terrestrial and freshwater biodiversity. Functional diversity measures provide substantial information on current and emerging impacts on biological communities, and aid conservation decisions relative to anthropogenic impacts. We determined (1) environmental similarities among 10 freshwater biotope types; (2) whether freshwater biotopes in conservation corridor networks support equal levels of functional richness and divergence compared with an extensive neighbouring protected area; (3) whether certain biotopes are more important for maintaining functional richness and divergence than others; and (4) whether associations between traits and biotope types could be identified. Location: The northeastern coastal region of South Africa. Methods: Using dragonflies as model organisms, and data from 140 freshwater lotic and lentic sites, we investigated the distribution of dragonfly traits across a plantation forestry‐natural grassland landscape mosaic with a range of biotope types. Results: Lake sites were different in their environmental conditions compared with the other biotopes. Environmental conditions were variable among the other biotope types and were difficult to distinguish. Freshwater biotopes in the conservation corridors supported equal levels of functional richness and divergence compared with those in the protected area. Overall, dragonfly functional richness and divergence were low at lake sites and wallows, while all other biotopes supported high levels of functional richness and divergence. Trait associations were complex across the waterscape and driven by habitat selection, flight behaviour and ecological sensitivity. Main Conclusions: Maintaining a mosaic of small lentic and lotic habitats would best support dragonfly conservation in this transformed landscape. A combination of biotopes offers a wide range of environmental conditions essential for conserving the full range of dragonfly traits and species across the region. [ABSTRACT FROM AUTHOR]

Mating between species occurs within many insect orders. The result of heterospecific mating depends upon the effectiveness of pre‐ and post‐reproductive barriers. Incomplete reproductive barriers lead to introgression of DNA into one species or both. Intricate genital morphology among dragonflies provides little assurance of species specificity given that heterospecific mating or mating attempts have been observed among many species. The genetic consequence is unknown for many heterospecific matings. For example, Somatochlora species mating and genetic exchange have been hypothesized based on observational records and individuals with hybrid morphology. We investigate the potential of heterospecific mating between North American Somatochlora species as inferred from multi‐gene phylogenies. We used mitochondrial genes (COI and ND3) and nuclear genes (EF1‐α and ITS2) to construct phylogenies using maximum parsimony. Observation of non‐monophyletic mtDNA lineages but monophyletic nDNA lineages between Somatochlora sister‐species would indicate mtDNA introgression and suggest heterospecific matings. Our results highlighted three instances of non‐monophyly of mtDNA clades in the following groups: (i) S. hineana + S. tenebrosa; (ii) S. kennedyi + S. forcipata + S. franklini; and (iii) S. calverti + S. provocans + S. filosa. Analysis of partitioned Bremer support indicates that mtDNA COI largely contributed to the non‐monophyly of these species, thus suggesting mtDNA introgression resulting from heterospecific matings. Additionally, the topology resulting from the combined data analysis was concordant with previous taxonomic understanding of Somatochlora species groups. These multi‐gene phylogenies of North American Somatochlora are the first, providing a foundation for future ecological and evolution studies and knowledge for effective decision‐making and public policy, which is especially important for the endangered species, S. hineana. [ABSTRACT FROM AUTHOR]

This study aimed to estimate macro-invertebrate distribution and diversity across different stations. We conducted an annual sampling of macro-invertebrates at two RAMSAR sites in the El Tarf region of Algeria over two successive cycles (2021-2023). Our sampling included nine stations, five in Lake Tonga and four in the Mekhada Marsh. 1909 specimens representing 76 taxa were identified, with 1233 originating from Lake Tonga and 676 from the Mekhada Marsh. Lake Tonga was the most abundant site, and Station S1 exhibited the highest diversity, while the Mekhada Marsh was the least diverse. Hemiptera and Odonata were the dominant orders. The analysis revealed severe environmental degradation in both sites, driven by anthropogenic activities and climatic changes. These findings underscore the urgent need for conservation measures to preserve these ecologically significant wetlands. [ABSTRACT FROM AUTHOR]

The article discusses the cytogenetic study of Nychogomphus duaricus and Scalmogomphus bistrigatus from the Gomphidae family in India, focusing on the origin and behavior of large X chromosomes during meiosis. The study reveals that the X chromosome is the largest element in the family Gomphidae, with the origin of the large X chromosome attributed to fusion with an autosome pair. Various staining techniques were used to analyze the chromosomes, providing insights into the evolution of sex-determining mechanisms and chromosome reduction in the family Gomphidae. [Extracted from the article]

We experimentally tested whether the presence of a free benthic predator (Odonata naiads) alters the displacement time, the position occupied in the water column, and the proportion of food consumed by benthic and nektonic tadpoles. The presence of predators did not influence the displacement time or the proportion of food consumed by any of the two species. In the presence of predators, benthic tadpoles avoided the benthic microhabitat, increasing their time in the middle of the water column. This behavior was unexpected since the previous studies indicate that the morphology of benthic tadpoles restricts them to the bottom of water bodies. We, thus, hypothesize that such a drastic behavior change was a consequence of the real risk of predation to which the tadpoles were exposed. Our results are in accordance with the threat-sensitivity hypothesis, in which prey behave flexibly when exposed to different degrees of predation threats. Nektonic tadpoles, however, slightly increased their permanence in the water column in the presence of the same benthic predators. Therefore, we provide support for the hypothesis that predators induce greater behavioral changes in prey that exhibit patterns of microhabitat use similar to theirs. [ABSTRACT FROM AUTHOR]

Liassophlebiidae is an extinct family of damsel-dragonflies found in Upper Triassic and Lower Jurassic strata of Europe, Asia and Antarctica. Whilst Liassophlebiidae is well represented by Lower Jurassic fossils, their lowest occurrence in the Upper Triassic has hitherto only been suggested by three fragmentary specimens. These were originally ascribed to two species: Liassophlebia withersi and Liassophlebia batheri, but the latter is now considered nomen dubium. Here we describe a fourth, better preserved specimen that is likely to be Rhaetian (Late Triassic) in age. The specimen, BRSMG Cg3101 a+b, was collected from Bowdens Quarry, Somerset, UK, from the lower part of the White Lias Formation. The specimen comprises an incomplete forewing attributed to Liassophlebia due to: the small number of antenodals, antesubnodals and crossveins between RP and MA based RP3/4 in the base of RP2 opposite the subnodus; a straight and elongate secondary longitudinal vein in the postdiscoidal area; numerous cells and secondary veins in radial and median areas. The specimen is likely to represent a new species and provides stronger evidence than the previous three specimens of the presence of Liassophlebiidae during the late Rhaetian. Its stratigraphical position suggests that Liassophlebiidae arose in the immediate aftermath of the Triassic-Jurassic mass extinction. [ABSTRACT FROM AUTHOR]

Simple Summary: The members of the order Odonata, commonly known as dragonflies and damselflies, play an essential role in freshwater ecosystems. However, identifying their rarity and conservation status is often difficult due to gaps between available data and existing knowledge. In this study, we employed the Rabinowitz rarity classification framework, using outputs from multispecies occupancy models that predict the occurrence of Odonata species in South Korea. We compared the results of these models with established information, such as geographic range, habitat preference, conservation status, and citizen science records. Our findings reveal that species with high need for conservation measures were typically identified as rare or data-deficient. However, notable discrepancies emerged, particularly for species traditionally regarded as common, often inhabiting lentic habitats. This highlights the necessity of standardized survey methods and improved access to data on legally protected species for accurate rarity assessments. Our study emphasizes the importance of enhancing survey protocols and data-sharing practices to provide more reliable species rarity evaluations and support effective conservation strategies for freshwater ecosystems. Accurate assessment of species rarity and conservation status requires an approach that integrates data-driven models with established ecological knowledge. In this study, we applied multispecies occupancy (MSO) and latent factor multispecies occupancy (LFMSO) models to estimate the occurrence of 133 Odonata species in South Korea. Using the model outputs, we implemented the Rabinowitz rarity framework to conduct data-based rarity assessments, which were then compared with known ecological information, including geographic ranges, habitat preferences, regional Red List statuses, and citizen science observations. Our findings reveal both alignments and discrepancies between these data-driven rarity assessments and traditional ecological knowledge. For example, species classified as near threatened (NT) or vulnerable (VU) on the regional Red List generally corresponded with high-rarity classifications based on the Rabinowitz framework. However, significant inconsistencies were identified, particularly for certain lentic Odonata species traditionally considered common. These results suggest that spatial biases in field surveys, combined with limited access to data on legally protected species, can impede accurate rarity assessments. These findings underscore the need for standardized survey protocols and improved data-sharing policies for sensitive species to reduce biases and enhance the reliability of rarity assessments. This is essential for effective conservation planning and biodiversity management in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Estimates of dark diversity, species that belong to a given species pool but are not present locally, can help to understand how environmental conditions influence species distribution. However, it remains uncertain whether dark diversity can predict the absence of indicator species in preserved environments after environmental changes. We explored the sensitivity of dark diversity (the set of species absent from a particular area), in detecting the absence of Zygoptera (Odonata) indicative of preserved forest environments in altered habitats, and the influence of sample coverage on the detected patterns. We sampled 98 streams in the Amazon region, where the dark diversity of Zygoptera was estimated based on probabilistic species co-occurrence patterns using the Beals index, encompassing 16 species in the Santarém/Belterra region and 23 species in the Paragominas region. The mean total richness of observed Zygoptera species in Paragominas, 42.7 species, and Santarém/Belterra, 25.93 species, was higher than the estimated mean dark diversity for the two study sites, which were 12.32 and 12.20 species, respectively. The dark diversity was not effective in detecting the absence of forest-indicator Zygoptera in human-altered streams and exhibited a positive relationship between Zygoptera dark diversity and species common to different environments concerning environmental integrity only in Paragominas, but not in Santarém. We found that there is a possibility that observed values of dark diversity may occasionally be subject to sampling coverage biases. In this regard, we suggest considering sampling coverage alongside field-collected biological datasets to assess whether it is related to dark diversity. [ABSTRACT FROM AUTHOR]

Se registró la fauna de odonatos adultos distribuidos en seis arroyos de la Reserva de la Biósfera Volcán Tacaná, durante las temporadas de luvia y de sequía entre octubre-noviembre de 2023 y enero-febrero 2024. Se contabilizó un total de 25 especies distribuidas en 11 géneros y siete familias. Con este estudio, el número de especies reportadas en la región Soconusco en el estado de Chiapas se incrementó a 88 especies. Además, se analizó la distintividad taxonómica promedio (∆+) de los ensamblajes de estos insectos y su varianza (λ+). Se evaluó la relación de ambas métricas con respecto a la elevación e integridad física de los arroyos, no encontrándose una relación entre éstas y la elevación de los arroyos, sin embargo, λ+ se asoció negativamente con la integridad física de los cuerpos de agua. Por lo tanto, ocurre una mayor uniformidad en la estructura taxonómica de los ensamblajes de odonatos en arroyos más conservados, debido especialmente a la integridad de su vegetación ribereña.

Sexual dimorphism is common throughout the animal kingdom, leading to sex-specific phenotypic differences. The common whitetail skimmer dragonfly, Plathemis lydia (Drury, 1773), is sexually dichromatic, where males of this species display a conspicuous white abdomen and females display a dark brown abdomen. Differences in abdomen conspicuousness between male and female P. lydia are likely attributed to differences in selective pressure where males use their white conspicuous abdomen during male-male territorial chases. We hypothesized that male P. lydia would exhibit wing morphology adaptations to better offset the costs of predation and territoriality and that these adaptations would differ from females. We used field-collected images to quantify differences in body length, wing length, wing area, wing shape, and wing loading between male and female P. lydia. Our results show that male P. lydia have significantly shorter fore and hind wings relative to body size with a higher wing loading when compared to females. We also found that male P. lydia have narrower and pointier fore and hind wings compared to females. These results are consistent with the idea that males are adapted for faster flight, specifically higher acceleration capacity, and higher agility whereas females are adapted for higher maneuverability.

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 Insect coloration has evolved in response to multiple pressures, and in Odonata (dragonflies and damselflies) a body of work supports a role of wing color in a variety of visual signals and potentially in thermoregulation. Previous efforts have focused primarily on melanistic coloration even though wings are often multicolored, and there has yet to be comprehensive comparative analyses of wing color across broad geographic regions and phylogenetic groups. Percher vs. flier flight-style, a trait with thermoregulatory and signaling consequences, has not yet been studied with regard to color. We used a new color clustering approach to quantify color across a dataset of over 8,000 odonate wing images representing 343 Nearctic species. We then utilized phylogenetically informed Bayesian zero-inflated mixture models to test how color varies with mean ambient temperature, body size, sex and flight-style. We found that wing coloration clustered into two groups across all specimens - light brown-yellow and black-dark brown - with black-dark brown being a much more cohesive grouping. Male perchers have a greater proportion of black-dark brown color on their wings as do species with longer wings. In colder climates, odonates were more likely to have black-dark brown color present, but we found no relationship between the proportion of black and temperature. Light brown-yellow showed similar scaling with wing length, but no relationship with temperature. Our results suggest that black-dark brown coloration may have a limited role in thermoregulation, while light brown-yellow does not have such a role. We also find that the odonate sexes are divergent in wing color in percher species only, suggesting a strong role for color in signaling in more territorial males. Our research contributes to an understanding of complex interactions driving ecological and evolutionary dynamics of color in animals.

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.

Aim: 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. Location: The Holarctic, including the entire Nearctic and the East and West Palaearctic. Taxon: 14 genera of Odonata (Insecta). Methods: 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. Results: 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. Main Conclusions: 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]

Colour polymorphism is an example of visible phenotypic variability that is often associated with ecological factors and may produce local adaptations. Small populations, particularly in islands, offer opportunities for evolutionary novelties, and are therefore of particular interest to the study of polymorphisms. Here we study the dynamics of female colour morphs in the damselfly Ischnura elegans in the Balearic Islands. We found that insular populations are small, show low density, low mating activity, and low androchrome frequency. Our surveys suggest that male harassment is a powerful force in the dynamics of this female-limited polymorphism, because high male densities result in lower presence of mature females around the water, where copulation takes place. Non-male-like (infuscans) females have higher mating frequency. Androchromes were rare (15%) in all populations, but the frequency of the two non-male like females (infuscans and aurantiaca) was reversed between islands, despite their geographical proximity. We found a possible novel morph, suggesting that insular conditions allow innovations. Fitness differences between the two non-male-like females of I. elegans are still understudied, because most previous research has concentrated on the maintenance of androchromes, and are therefore a priority for future research. [ABSTRACT FROM AUTHOR]

Functional diversity is a key component of biodiversity that reflects various dimensions of ecosystem functioning and the roles organisms play within communities and ecosystems. It is widely used to understand how ecological processes influence biotic assemblages. With an aim to increase our knowledge about dragonfly ecological requirements in tufa-depositing karst habitats, we assessed functional diversity of their assemblages, various life history traits (e.g., stream zonation preference, substrate preference, reproduction type), and relationship between functional diversity and physico-chemical water properties in three types of karst lotic habitats (springs, streams, and tufa barriers) in a biodiversity hotspot in the western Balkan Peninsula. Dragonfly functional diversity was mainly characterized by traits typical for lotic rheophile species with medium dispersal capacity. Among the investigated habitats, tufa barriers, characterized by higher (micro)habitat heterogeneity, higher water velocity, as well as lower conductivity and concentration of nitrates, can be considered as dragonfly functional diversity hotspots. Functional diversity and most of the life history traits were comparable among different substrate types in the studied habitats, indicating higher importance of habitat type in shaping dragonfly functional diversity patterns in karst lotic habitats. Our results should be considered in the management and conservation activities of vulnerable karst freshwater ecosystems and their dragonfly assemblages. [ABSTRACT FROM AUTHOR]

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]

Present research has shown that zoogeographic barriers can have a significant impact on biodiversity. Türkiye has numerous ecobiological barriers and there has been an increase in research on the impact of the Anatolian diagonal on biodiversity. The objective of this study is to examine the variations in wing morphology of Platycnemis dealbata (Selys and Hagen, 1850) in different populations separated by the Anatolian Diagonal. To achieve this objective, the intraspecies wing variation of three different P. dealbata populations collected from the provinces of Iğdır and Hatay in the east of the Anatolian diagonal and Mersin in the west were investigated using geometric morphometry method. The findings of this study support the idea that the Anatolian diagonal acts as a barrier for P. dealbata populations. [ABSTRACT FROM AUTHOR]

Benthic macroinvertebrate abundance and taxa richness associated with environmental variables were monitored monthly from September 2015 to August 2016 in the Nyamuhinga River. The benthic macroinvertebrate samples were collected using a D-frame aquatic net employing the man-time method. Environmental variables including pH, temperature, conductivity, and total dissolved solids (TDS) were measured using a Combo HI 98129 and GREISIN-GER 020 multimeters, and water flow was assessed using the Float Method procedure. The Shannon–Wiener and equitability indices were then calculated to assess diversity and richness, facilitating the comparison of diversity within sites or stations. A total of 35,142 macroinvertebrate individuals were collected from the 12 sampling sites belonging to 29 genera, 27 families, and 9 orders. Diptera were the most abundant (71.83%) followed by Odonata (9.13%) and Ephemeroptera (7.11%). The findings showed that taxa richness decreased from upstream to downstream. At the same time, absolute abundance increased from downstream to upstream due to riparian vegetation, substrate type, plant debris, and organic matter which are habitats for benthic macroinvertebrates in the river. Environmental variables such as flow, pH, temperature, conductivity, and TDS varied between sites and stations because of habitat disturbances, contaminant discharges into the catchment, and inflow of tributary waters into the river. The canonical correspondence analysis (CCA) results displayed that Eristalis and Chironomus were strongly associated with the flow, conductivity, TDS, temperature, and pH at the downstream sites related to anthropogenic activities from the catchment. From our results, the Nyamuhinga River needs conservation master plan/guidelines and increased awareness to reduce environmental impacts in Bukavu River catchments in the Lake Kivu basin. [ABSTRACT FROM AUTHOR]

Orthetrum sabina is one of the most common dragonflies found in Nepal, but its feeding behavior has not often been reported from there. An example of this species preying on Neurothemis tullia is reported from Maidi Lake, Nepal. This observation was made during a field survey of Odonata using direct observation along transects around the lake. It adds to our knowledge of the species' feeding behavior, elaborating the previous findings and providing scope for further ecological studies on Odonata. [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]

During a field expedition in the municipality of Araquari, state of Santa Catarina, southern Brazil, adults of the damselfly Cyanallagma demoiselle Denck, Ehlert & Pinto 2023 (Odonata, Zygoptera, Coenagrionidae) were collected. This species was recently described and reported to date for the southeastern Atlantic Forest in Brazil. Here, we recorded this species as well as its respective genus for the first time for the state of Santa Catarina, increasing its distribution range of the species to southwards and raising the number of Odonata species recorded for this state to 151. [ABSTRACT FROM AUTHOR]

Documenting the distribution of species is necessary as the first step to assess their responses to both anthropogenic disturbance and ongoing climate change. Among insects, some orders, including butterflies (Lepidoptera), dragonflies (Odonata), and families, such as ladybird beetles (Coccinellidae) and tiger beetles (Cicindelidae), have received both scientific focus and public attention. In particular, tiger beetles are a diverse, charismatic group of insect predators that occur in habitats with bare soil and are generally well-documented. Because of its geographic location and numerous ecoregions, Oklahoma has many insect species that occur at their eastern, western, northern, and southern edges. A total of 36 species of tiger beetles have previously been documented in the state. Here, we report the occurrence of three additional species, which add approximately 10% to the known occurrence of tiger beetles in Oklahoma. We documented Amblycheila picolominii, a large, nocturnal tiger beetle known from the southwestern United States, which has extended its range by more than 300 km. We also documented Cicindela limbalis, a species typically found on clay in northern North America, and Cicindelidia sedecimpunctata, which is found in the southwestern United States into Mexico. Updating the occurrence of the insects' range, especially for popular insects, can lead to increased study and better baseline data for future research. [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]

Applying BEAST v1.10.4, we constructed a Bayesian Inference tree comprising 322 taxa, primarily representing Paleoptera (Odonata and Ephemeroptera; Pterygota), Zygentoma and Archaeognatha (Apterygota; paraphyly), and Neoptera (Plecoptera; Pterygota), based on a 2685 bp sequence dataset. Our analyses revealed that robust dating required the incorporation of both Quaternary and pre‐Quaternary dates. To achieve this, our dating incorporated a 1.55 Ma (Quaternary) geological event (the formation of the Ryukyu Islands) and a set of chronologically well‐founded fossil dates, spanning from up to 400 Ma (Devonian) for the stem Archaeognatha, 320 Ma (Carboniferous) for the crown of Paleoptera, 300 Ma (Carboniferous) for the crown Ephemeroptera, and 280 Ma (Permian) for the crown Odonata, down to 1.76 Ma (Quaternary) for Calopteryx japonica, encompassing a total of 22 calibration points (events: 6, fossils: 16; Quaternary: 7, pre‐Quaternary: 15). The resulting dated tree aligns with previous research, albeit with some dates being overestimated. This overestimation was mainly due to the lack of Quaternary calibration and the exclusive dependence on pre‐Quaternary calibration, though the application of maximum age constraints also played a role. Our minimum age dating demonstrates that the molecular clock did not uniformly progress, rendering rate dating an inapplicable approach. We observed that the base substitution rate is time‐dependent, with an exponential increase evident from around 20 Ma (Miocene) to the present time, exceeding an order of magnitude. The extensive radiation and speciation of Insecta and Paleoptera, potentially resulting from the severe climatic changes associated with the Quaternary, including the commencement of glacial and interglacial cycles, may have significantly contributed to this increase in base substitution rates. Additionally, we identified a potential peak in base substitution rates during the Carboniferous period, around 320 million years ago, possibly corresponding to the Late Paleozoic Ice Age. [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]

Odonates (dragonflies and damselflies) have become popular study organisms for insect-based climate studies, due to the taxon's strong sensitivity to environmental conditions, and an enthusiastic following by community scientists due to their charismatic appearance and size. Where formal records of this taxon can be limited, public efforts have provided nearly 1,500,000 open-sourced odonate records through online databases, making real-time spatio-temporal monitoring more feasible. While these databases can be extensive, concerns regarding these public endeavors have arisen from a variety of sources: records may be biased by human factors (ex: density, technological access) which may cause erroneous interpretations. Indeed, records of odonates in the east-central US documented in the popular database iNaturalist bear striking patterns corresponding to political boundaries and other human activities. We conducted a 'ground-truthing' study using a structured sampling method to examine these patterns in an area where community science reports indicated variable abundance, richness, and diversity which appeared to be linked to observation biases. Our observations were largely consistent with patterns recorded by community scientists, suggesting these databases were indeed capturing representative biological trends and raising further questions about environmental drivers in the observed data gaps. [ABSTRACT FROM AUTHOR]

We present the distinctive morphological characteristics of Tramea limbata from other species of the Tramea family. While the adult species is well documented, the nymph of Tramea limbata is not described in the literature. The nymphs of Tramea limbata are robust, greenish-yellow and translucent aquatic insects while alive, and their exuviae are straw-brown. The exuvial characteristics match well with the final instar and are sufficient to identify the species. Notably, in T. limbata, compared to T. binotata and other species, the appendages exhibit distinct patterns; the tibia and tarsus are adorned with comb-like tufts of setae, and the femur bears stout spines. Also, the lack of spiniform setae on the dorsal region of the tergum of abdominal segments, particularly segments 6 to 9, gives them a smooth appearance. Another characteristic of T. limbata is that the epiproct and paraproct are half the length of the cerci. The labium is spoon-shaped with a pair of labial palps with ten short inner palpal setae, 12 long outer palpal setae, and a pair of movable palpal hooks at the distal margin. Premental setae are 16 in number on either side. The anterior margin of the head of T. limbata is characterised by ten crenulations ending in short, stout spiny setae, extending up to the width of the lower jaw. These features help to distinguish Tramea limbata nymphs from strikingly similar nymphs of other Tramea species, and their exuvia provides a noninvasive approach to conservation studies. [ABSTRACT FROM AUTHOR]

Genus Pseudagrion is one of the largest genera of order Odonata and 14 species of this genus have been reported in India. The current research aims to reconstruct the phylogenetic trees by amplifying the partial sequences of the following three mitochondrial genes: COI, ND1 and 16 S rRNA genes, to produce a DNA reference library and determine the evolutionary relationships among the species of genus Pseudagrion. Sequences of mitochondrial genes of eight species have been submitted to NCBI, out of which Pseudagrion decorum, P. hypermelas and P. indicum barcoded for the first time. Since no work has been reported to far for CUB in genus Pseudagrion, the MT-ND1 gene appears to be a good choice for analyzing codon usage pattern. Codon usage bias for mitochondrial genes is low because of high effective number of codons. The most frequent codons, favored A or T at the 3rd codon position which indicate the significant role of compositional constraint in codon usage bias. Genetic divergence based on COI and 16 S rRNA ranges from 2.4 to 15.8%. 12 S rRNA and 16 S rRNA genes show minor genetic diversity, whereas NDI and COI genes reveal higher genetic diversity because of high mutation rate. In phylogenetic tree, 34 Pseudagrion species get segregated into five major clades as: ((P. pruinosum + P. spencei + P. hypermelas + P. rubriceps) + P. microcephalum) + (P. decorum + P. indicum + P. australasiae) + ((P. aureolum) + P. massaicum + P. tanganyicum + P. hamoni + P. pacale + P. niloticum + P. acacia) + (P. ignifer + P. pilidorsum + P. pruinosum) + ((P. dactylidium) + P. bicoerulans + P. munte + P. sarepi + P. kersteni) that depicts their evolutionary relationships. [ABSTRACT FROM AUTHOR]

Riverine caves are special habitats that are home to many aquatic and terrestrial species. Some Odonata species and their emerging are recorded at the entrance and in the twilight zones of subterranean habitats around the world. However, the emergence of any Odonata species has not been recorded in the dark zones of caves or other subterranean habitats. We report the first evidence of the emerging of the Hyrcanian Goldenring, Cordulegaster vanbrinkae Lohmann, 1993, as an endemic species of the Hyrcanian biogeographical region, in the dark zone of Danial Cave, in the World Heritage‐listed Hyrcanian Forests, northern Iran. During 2020–2023, three newly emerged and three exuviae of the species were recorded in the entrance zone (25 m) and the dark zone of the cave (200–280 m). The main hypothesis of the study is the entry and exit of adults from the cave entrance. However, we still do not know if the newly emerged will leave the cave or not. We still need more study on the biology and ecology of the species inside and around the cave. Danial Cave, with its high biodiversity, is one of the most important caves in the Middle East, and is urgently in need of conservation as a national natural monument. [ABSTRACT FROM AUTHOR]

Pantala flavescens (Fabricius) is the most well‐known seasonal migratory insect. This research focused on the molecular response of P. flavescens migration in summer and fall. A total of 17,810 assembled unigenes were obtained and 624 differentially expressed genes (DEGs) were identified in summer migration compared to fall migration. A number of DEGs, including cpr49Ae, itm2b, chitinase, cpr11B, laccase2, nd5, vtg2 and so on, had previously been reported to be involved in cold‐ and high‐temperature resistance. Functional enrichment analysis showed three pathways 'that antibacterial humoral response, response to bacterial, and lipid transporter activity' were significantly enriched in summer migration while that six pathways 'structural constituent of cuticle, chitin binding, mitochondrion, propanoate metabolism, citrate cycle, hypertrophic cardiomyopathy' were significantly enriched in fall migration. These results will provide a valuable baseline for further understanding of the molecular mechanisms of insect adaptation to different climate migrations. [ABSTRACT FROM AUTHOR]

In floodplains, which are highly modified and less inundated, trees are expanding, thus raising concerns regarding their impact on freshwater organisms. We analyzed the relationship between forest expansion and the change in Odonata (dragonflies and damselflies) assemblage over an extended period of time in the floodplain with ponds of the Kiso River, central Japan. In the 1970s, the ponds were mainly surrounded by grasslands, and approximately 80% of Odonata species were non-forest species. However, the number of forest species increased and that of non-forest species largely decreased with the forest expansion over the past five decades, resulting in almost a similar number of forest and non-forest species in 2021. Whereas the abundance of the non-forest species had been greater than that of the forest species until the 2000s, the difference has been much smaller in the 2010s, and the non-forest species occupied approximately only 30% of the number of individuals in 2021. The forest expansion may have reduced the open-lentic habitats for the non-forest species, which require riparian grasslands for resting, foraging, and reproduction, and may disturb the immigration of non-forest species from the adjacent rice paddy fields and rivers. The development of canopy cover over the waterbodies may have decreased the light and temperature above and within the ponds, which might have caused a decline in species that prefer warm and open-water environments. Maintaining shifting-mosaic patterns of vegetation around the floodplain waterbodies through active management may be effective in conserving floodplain Odonata communities, including both forest and non-forest species. [ABSTRACT FROM AUTHOR]

Simple Summary: Cordulegastridae, recognized for their striking black-and-yellow colouring, are robust and large dragonflies typically found in clean running springs and streams, which are unfortunately facing significant threats worldwide. Currently, 52 species are listed in this family. Cordulegastridae are remarkably uniform in the structure of the male appendages and the female valvular scale, while the pattern of yellow markings on the abdomen and thorax may vary even within a taxon. This often results in confusion regarding the identification, distribution, and intraspecific division of many species in this family. To address these challenges, we undertook a molecular phylogenetic analysis of this family. Our analyses supported most of the traditional genera. The well-known bidentata group of the current Cordulegaster, including C. coronata and its sister species C. brevistigma, was transferred by us to the genus Thecagaster. The genus Neallogaster remained unresolved. However, Cordulegaster pekinensis, currently known as Neallogaster pekinensis, was placed by us in the genus Thecagaster as well. The genus Zoraena stat. rev. was recovered to include most of the American members of Cordulegastridae, except for C. virginiae and, tentatively, C. diadema, which were retained in the genus Cordulegaster along with the members of the Cordulegaster boltonii group. The monophyly of the genus Anotogaster was confirmed, and three dubious species of this genus were synonymized. Our revision provides a clearer understanding of the evolutionary relationships and taxonomic framework of the family Cordulegastridae. In this study, we present the first attempt at a molecular phylogenetic analysis of the entire family of Cordulegastridae involving 60% of its known species. Our analysis is in favor of reclassification of the members of the family into four genera: (i) the monophyletic genus Anotogaster Selys, 1854, with the number of known species reduced by three synonymizations; (ii) the genus Cordulegaster Leach in Brewster, 1815 including all members of the boltonii group and, as a preliminary solution, the American species C. virginiae Novelo-Gutiérrez, 2018 and, very tentatively, C. diadema Selys, 1868. The bidentata group forms a genus of its own, for which we restored the name Thecagaster Selys 1854, stat. rev. Cordulegaster pekinensis McLachlan in Selys, 1886, currently considered as Neallogaster pekinensis, was placed by us in Thecagaster as well. The genus Neallogaster Cowley, 1934 needs further investigation involving all remaining species listed in it. The genus Zoraena Kirby, 1890, stat. rev., was recovered to accommodate the remaining American species of Cordulegaster. We synonymized three species of Anotogaster: Anotogaster gregoryi Fraser, 1923 = Anotogaster xanthoptera Lohmann, 1993, syn. nov.; Anotogasterkuchenbeiseri (Förster, 1899) = Anotogaster antehumeralis Lohmann, 1993, syn. nov.; Anotogaster kuchenbeiseri (Förster, 1899) = Anotogaster cornutifrons Lohmann, 1993, syn. nov., based on examination of the existing type specimens. The type of specimens of A. klossi Fraser, 1919 = A. flaveola Lohmann 1993 syn. confirm., were also examined, and their synonymy was confirmed. The isolated populations of A. sieboldii (Selys, 1854) from the archipelagos of Okinawa and Amami Oshima in Japan, respectively, should be regarded as separate species, which will be described elsewhere. Furthermore, we suggest the synonymization of Cordulegaster parvistigma Selys 1873 syn. nov. with Thecagaster brevistigma (Selys 1854) comb. restaur. [ABSTRACT FROM AUTHOR]

In a two-year field study across 58 isolated wetlands in Texas (USA), we examined whether odonate (Insecta: Odonata) assemblages were structured by local environmental filters or instead simply reflected the use of any available water in this semi-arid region. Cluster analysis resolved three wetland groupings based on environmental characteristics (hydroperiod, water chemistry, vegetation); 37 odonate species were detected at these wetlands. The most speciose assemblages occurred at wetlands with longer hydroperiods; these sites also had the most species found at no other wetland type. Ordination plots indicated some filtering with respect to the hydroperiod, but there was only mixed or weak support with respect to other local factors. Because water persistence was the strongest driver maintaining odonate diversity in this region, regardless of water quality or vegetation, beggars cannot be choosers in this system and conservation efforts can focus on water maintenance or supplementation. [ABSTRACT FROM AUTHOR]

Insects, despite possessing relatively small brains, exhibit noteworthy adaptive behaviors, making them intriguing subjects for understanding learning mechanisms. This study explores the learning capabilities of dragonfly larvae (Anisoptera: Aeshnidae) in conditioning experiments, shedding light on the cognitive processes that underpin their remarkable abilities. As apex predators, dragonflies play a crucial role in ecosystems, necessitating a diverse range of learning behaviors for survival and reproductive success. We addressed whether dragonfly larvae can differentiate between different colored stimuli and associate color with prey. Our experimental design demonstrated that dragonfly larvae are able to recognize conditioning stimuli. The findings contribute valuable insights into the cognitive abilities of dragonflies, suggesting that these insects can learn and discriminate colors of stimuli. Overall, this research broadens our understanding of insect learning and cognition, contributing to the broader field of animal behavior and memory. [ABSTRACT FROM AUTHOR]

Odonates are widely considered to be bioindicators of freshwater habitat quality. Somatochlora arctica (Corduliidae) is commonly found across Eurasia, predominantly in North and Central Europe, but in the UK, it has a restricted range and is listed as near threatened despite a large, potential habitat availability. Across their range, larvae are found in Sphagnum-filled bog pools near coniferous woodlands, but detailed data on their habitat requirements are limited and often overlooked in favour of adult surveys which inhibits conservation efforts. This study surveyed three areas across Scotland: Abernethy & Loch Garten National Nature Reserve (NNR), Beinn Eighe NNR and Flanders Moss NNR, to evaluate how different environmental factors per pool (e.g. water depth and chemistry, Sphagnum coverage, woodland distance, etc.) affect the presence of S. arctica larvae. We found a higher occurrence of S. arctica larvae when pools were located close to woodlands (i.e. 0–10 m), and had high coverage of Sphagnum (> 90%). Environmental variables in pools surveyed (i.e. conductivity, water depth, pH and water temperature) had no significant effects on S. arctica presence. Implications for insect conservation: Our results highlight and discuss the importance of nearby woodlands and Sphagnum cover for S. arctica larvae. Future conservation projects should consider the proximity of woodland to current and restored S. arctica sites or promoting expansion of surrounding natural woodland patches to benefit S. arctica and potentially other odonates sharing similar ecological preferences. [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]

BACKGROUND: The rise of insecticide resistance against malaria vectors in sub-Saharan Africa has resulted in the need to consider other methods of vector control. The potential use of biological methods, including larvivorous fish, Bacillus thuringiensis israelensis (Bti) and plant shading, is sustainable and environmentally friendly options. This study examined the survivorship of Anopheles arabiensis and Anopheles funestus larvae and habitat productivity in four permanent habitat types in Homa Bay county, western Kenya. METHODS: Predator densities were studied in a laboratory setup while habitat productivity and larval survivorship was studied in field setup. RESULTS: Fish were observed as the most efficient predator (75.8% larval reduction rate) followed by water boatman (69%), and dragonfly nymph (69.5%) in predation rates. Lower predation rates were observed in backswimmers (31%), water beetles (14.9%), water spiders (12.2%), mayflies (7.3%), and tadpoles (6.9%). Increase in predator density in the field setup resulted in decreased Culex larval density. Larval and pupa age-specific distribution was determined and their survivorship curves constructed. Combined larvae (Stage I-IV) to pupa mortality was over 97% for An. arabiensis and 100% for An. funestus. The highest larval stage survival rate was from larval stages I to II and the lowest from larval stage IV to pupa. Stage-specific life tables indicated high mortality rates at every developmental stage, especially at the larval stage II and III. CONCLUSION: Determination of the efficiency of various larval predators and habitat productivity will help with the correct identification of productive habitats and selection of complementary vector control methods through environmental management and/or predator introduction (for instance fish) in the habitats.