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Antonio Ruggiero - One of the best experts on this subject based on the ideXlab platform.
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Habitat characteristics and Odonate diversity in mountain ponds of central Italy
Aquatic Conservation: Marine and Freshwater Ecosystems, 2005Co-Authors: Gianmaria Carchini, Angelo G. Solimini, Antonio RuggieroAbstract:1. In central Italy mountain ponds represent an important habitat for the conservation of dragonflies; however, human disturbance of these fragile environments is threatening the stability of their biodiversity. 2. Thirty-one ponds, ranging in altitude from 1014 to 2004 m, were qualitatively sampled for Odonate larvae twice during 1998. On each occasion a range of physical, chemical and biotic habitat variables were also measured. 3. The mountain ponds sampled had fewer species of Odonata than lowland ponds, and there was a large presence of pioneer species. 4. Multiple regression analysis showed that the number of Odonate species was positively affected by the amount of macrophyte coverage of the pond surface and negatively affected by increasing ammonium concentration. 5. A Canonical Correspondence Analysis revealed that species number decreased with altitude, chlorophyll a and phosphorus concentrations. The presence/absence of each Odonate species was weakly related to the habitat variables. 6. The intensive use of ponds for livestock watering results in damage to the peripheral vegetation, which tends to cause high turbidity and lower macrophyte coverage of the pond water. The inevitable outcome in these situations is a reduction of the Odonate diversity.
Erik I. Svensson - One of the best experts on this subject based on the ideXlab platform.
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The Odonate phenotypic database, a new open data resource for comparative studies of an old insect order.
Scientific data, 2019Co-Authors: John T. Waller, Beatriz Willink, Maximilian Tschol, Erik I. SvenssonAbstract:We present The Odonate Phenotypic Database (OPD): an online data resource of dragonfly and damselfly phenotypes (Insecta: Odonata). Odonata is a relatively small insect order that currently consists of about 6400 species belonging to 32 families. The database consists of multiple morphological, life-history and behavioral traits, and biogeographical information collected from literature sources. We see taxon-specific phenotypic databases from Odonata and other organismal groups as becoming an increasing valuable resource in comparative studies. Our database has phenotypic records for 1011 of all 6400 known Odonate species. The database is accessible at http://www.Odonatephenotypicdatabase.org/, and a static version with an information file about the variables in the database is archived at Dryad.
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The Odonate phenotypic database, a new open data resource for comparative studies of an old insect order
Scientific Data, 2019Co-Authors: John T. Waller, Beatriz Willink, Maximilian Tschol, Erik I. SvenssonAbstract:We present The Odonate Phenotypic Database (OPD): an online data resource of dragonfly and damselfly phenotypes (Insecta: Odonata). Odonata is a relatively small insect order that currently consists of about 6400 species belonging to 32 families. The database consists of multiple morphological, life-history and behavioral traits, and biogeographical information collected from literature sources. We see taxon-specific phenotypic databases from Odonata and other organismal groups as becoming an increasing valuable resource in comparative studies. Our database has phenotypic records for 1011 of all 6400 known Odonate species. The database is accessible at http://www.Odonatephenotypicdatabase.org/ , and a static version with an information file about the variables in the database is archived at Dryad. Measurement(s) Invertebrate Taxonomy • body length • wing • appendage morphology trait • mating behavior • flight behavior • habitat • ecozone • climate • sexual dimorphism • size • color • biological pigment Technology Type(s) digital curation Factor Type(s) phenotypes Sample Characteristic - Organism Zygoptera • Anisoptera Sample Characteristic - Environment stream • pond • wetland ecosystem • lake • river • ephemeral spring Sample Characteristic - Location South America • North America • Africa • Asia • Europe • Australia Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.10321595
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body size evolution in an old insect order no evidence for cope s rule in spite of fitness benefits of large size
Evolution, 2017Co-Authors: John T. Waller, Erik I. SvenssonAbstract:We integrate field data and phylogenetic comparative analyses to investigate causes of body size evolution and stasis in an old insect order: Odonates (“dragonflies and damselflies”). Fossil evidence for “Cope's Rule” in Odonates is weak or non-existent since the last major extinction event 65 million years ago, yet selection studies show consistent positive selection for increased body size among adults. In particular, we find that large males in natural populations of the banded demoiselle (Calopteryx splendens) over several generations have consistent fitness benefits both in terms of survival and mating success. Additionally, there was no evidence for stabilizing or conflicting selection between fitness components within the adult life-stage. This lack of stabilizing selection during the adult life-stage was independently supported by a literature survey on different male and female fitness components from several Odonate species. We did detect several significant body size shifts among extant taxa using comparative methods and a large new molecular phylogeny for Odonates . We suggest that the lack of Cope's rule in Odonates results from conflicting selection between fitness advantages of large adult size and costs of long larval development. We also discuss competing explanations for body size stasis in this insect group. This article is protected by copyright. All rights reserved
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odonata dragonflies and damselflies as a bridge between ecology and evolutionary genomics
Frontiers in Zoology, 2016Co-Authors: Seth M. Bybee, Alex Cordobaaguilar, Catherine M Duryea, Ryo Futahashi, Bengt Hansson, Olalla M Lorenzocarballa, Rudolf J Schilder, Robby Stoks, Anton Suvorov, Erik I. SvenssonAbstract:Odonata (dragonflies and damselflies) present an unparalleled insect model to integrate evolutionary genomics with ecology for the study of insect evolution. Key features of Odonata include their ancient phylogenetic position, extensive phenotypic and ecological diversity, several unique evolutionary innovations, ease of study in the wild and usefulness as bioindicators for freshwater ecosystems worldwide. In this review, we synthesize studies on the evolution, ecology and physiology of Odonates, highlighting those areas where the integration of ecology with genomics would yield significant insights into the evolutionary processes that would not be gained easily by working on other animal groups. We argue that the unique features of this group combined with their complex life cycle, flight behaviour, diversity in ecological niches and their sensitivity to anthropogenic change make Odonates a promising and fruitful taxon for genomics focused research. Future areas of research that deserve increased attention are also briefly outlined.
James H. Kennedy - One of the best experts on this subject based on the ideXlab platform.
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seasonality of Odonate mediated methylmercury flux from permanent and semipermanent ponds and potential risk to red winged blackbirds agelaius phoeniceus
Environmental Toxicology and Chemistry, 2017Co-Authors: Edward B. Williams, Matthew M. Chumchal, Ray W. Drenner, James H. KennedyAbstract:Methylmercury (MeHg) is an aquatic contaminant that can be transferred to terrestrial predators by emergent aquatic insects such as Odonates (damselflies and dragonflies). We assessed the effects of month and pond permanence on Odonate-mediated MeHg flux (calculated as emergent Odonate biomass × MeHg concentration) in 10 experimental ponds and the potential risk to nestling red-winged blackbirds (Agelaius phoeniceus) posed by consuming MeHg-contaminated Odonates. Emergent Odonates were collected weekly from permanent ponds with bluegill (Lepomis macrochirus; n = 5) and semipermanent ponds without fish (n = 5) over an 8-mo period (January-August 2015). The MeHg flux from damselflies, aeshnid dragonflies, and libellulid dragonflies began in March and peaked in April, May, and June, respectively, and then declined throughout the rest of the summer. Odonate-mediated MeHg flux from semipermanent ponds without fish was greater than that from permanent ponds with fish. Nesting of red-winged blackbirds overlapped with peak Odonate emergence and Odonate-mediated MeHg flux. Because their diet can be dominated by damselflies and dragonflies, we tested the hypothesis that MeHg-contaminated Odonates may pose a health risk to nestling red-winged blackbirds. Concentrations of MeHg in Odonates exceeded wildlife values (the minimum Odonate MeHg concentrations causing physiologically significant doses in consumers) for nestlings, suggesting that MeHg-contaminated Odonates can pose a health risk to nestling red-winged blackbirds. Environ Toxicol Chem 2017;36:2833-2837. © 2017 SETAC.
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Seasonality of Odonate‐mediated methylmercury flux from permanent and semipermanent ponds and potential risk to red‐winged blackbirds (Agelaius phoeniceus)
Environmental Toxicology and Chemistry, 2017Co-Authors: Edward B. Williams, Matthew M. Chumchal, Ray W. Drenner, James H. KennedyAbstract:: Methylmercury (MeHg) is an aquatic contaminant that can be transferred to terrestrial predators by emergent aquatic insects such as Odonates (damselflies and dragonflies). We assessed the effects of month and pond permanence on Odonate-mediated MeHg flux (calculated as emergent Odonate biomass × MeHg concentration) in 10 experimental ponds and the potential risk to nestling red-winged blackbirds (Agelaius phoeniceus) posed by consuming MeHg-contaminated Odonates. Emergent Odonates were collected weekly from permanent ponds with bluegill (Lepomis macrochirus; n = 5) and semipermanent ponds without fish (n = 5) over an 8-mo period (January-August 2015). The MeHg flux from damselflies, aeshnid dragonflies, and libellulid dragonflies began in March and peaked in April, May, and June, respectively, and then declined throughout the rest of the summer. Odonate-mediated MeHg flux from semipermanent ponds without fish was greater than that from permanent ponds with fish. Nesting of red-winged blackbirds overlapped with peak Odonate emergence and Odonate-mediated MeHg flux. Because their diet can be dominated by damselflies and dragonflies, we tested the hypothesis that MeHg-contaminated Odonates may pose a health risk to nestling red-winged blackbirds. Concentrations of MeHg in Odonates exceeded wildlife values (the minimum Odonate MeHg concentrations causing physiologically significant doses in consumers) for nestlings, suggesting that MeHg-contaminated Odonates can pose a health risk to nestling red-winged blackbirds. Environ Toxicol Chem 2017;36:2833-2837. © 2017 SETAC.
David J Thompson - One of the best experts on this subject based on the ideXlab platform.
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identifying high quality pond habitats for odonata in lowland england implications for agri environment schemes
Insect Conservation and Diversity, 2012Co-Authors: Eva M Raebel, Thomas Merckx, Ruth E Feber, Philip Riordan, David W Macdonald, David J ThompsonAbstract:1. Agricultural intensification has contributed to severe declines in Odonate (dragonfly and damselfly) populations. The objective of our study is to benefit current measures for the conservation of Odonates by establishing the conditions favourable to Odonata and focusing on ponds within agricultural land. 2. Our landscape-scale study used exuvial counts and habitat measurements from 29 ponds across a catchment in England, over 3 years, to determine key factors affecting Odonate abundance and species richness. 3. Ponds dominated by floating and submerged vegetation were the most transparent, supported the highest abundance and species richness of exuviae, and were always fully or partially surrounded by buffer strips. Ponds lacking vegetation were turbid, yielding no exuviae even if they were buffered. English agri-environment schemes (AES) currently support pond and buffer strip creation and management. 4. Abundance of exuviae was higher in recently created ponds compared to older ponds, whereas ponds that had dried out the previous summer had fewer exuviae. 5. Species richness of exuviae decreased with increasing distance to the nearest viable pond, falling by more than 40% for distances over 100 m. 6. We conclude that Odonate conservation would be more effective if AES would consider the spatial scale at which ponds are created and the location, type, and quality of ponds targeted for buffer strips.
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the dragonfly delusion why it is essential to sample exuviae to avoid biased surveys
Journal of Insect Conservation, 2010Co-Authors: Eva M Raebel, Thomas Merckx, Philip Riordan, David W Macdonald, David J ThompsonAbstract:Odonate populations and species numbers are declining globally. Successful conservation requires sound assessments of both Odonate distributions and habitat requirements. Odonates have aquatic (larval) and terrestrial (adult) stages, but most surveys that are used to inform conservation managers are undertaken of the adult stage. This study investigates whether this bias towards adult records in Odonate recording is misinterpreting the environmental quality of sites. The habitat focus is farmland ponds, a key feature of agricultural landscapes. We tested whether or not, adult, larval and exuvial surveys lead to similar conclusions on species richness and hence on pond quality. Results showed that pond surveys based upon larvae and exuviae are equally suitable for the reliable assessment of presence/absence of Odonates, but that adult surveys are not interchangeable with surveys of larvae/exuviae. Larvae were also found at ponds with no emerging individuals due to changes in habitat quality, therefore presence of exuviae remains the only proof of life-cycle completion at a site. Ovipositing females were recorded at all ponds where exuviae were totally absent hence adult surveys over-estimate pond quality and low-quality ponds are functioning as ecological traps. Highly mobile and generalist species were recorded at more locations than other species. Adult surveys also bias recording towards genera, species and populations with non-territorial mate-location strategies. Odonate biodiversity monitoring would benefit from applying the best survey method (exuviae) to avoid wasting valuable financial resources while providing unbiased data, necessary to achieve conservation objectives.
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historical changes in the phenology of british odonata are related to climate
Global Change Biology, 2007Co-Authors: Christopher Hassall, David J Thompson, G C French, Ian F HarveyAbstract:Responses of biota to climate change take a number of forms including distributional shifts, behavioural changes and life history changes. This study examined an extensive set of biological records to investigate changes in the timing of life history transitions (specifically emergence) in British Odonata between 1960 and 2004. The results show that there has been a significant, consistent advance in phenology in the taxon as a whole over the period of warming that is mediated by life history traits. British Odonates significantly advanced the leading edge (first quartile date) of the flight period by a mean of 1.51 ±0.060 (SEM, n=17) days per decade or 3.08±1.16 (SEM, n=17) days per degree rise in temperature when phylogeny is controlled for. This study represents the first review of changes in Odonate phenology in relation to climate change. The results suggest that the damped temperature oscillations experienced by aquatic organisms compared with terrestrial organisms are sufficient to evoke phenological responses similar to those of purely terrestrial taxa.
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Exuviae as a reliable source of DNA for population-genetic analysis of Odonates
Odonatologica, 2005Co-Authors: Phillip C. Watts, David J Thompson, C. Daguet, Stephen J. KempAbstract:Genetic analyses are widely used for a variety of ecological research, especially to aid species' conservation programs. Where genetic material is required from rare endangered species it is essential that the samples be collected non-destructively, the ultimate goal should be to develop reliable DNA extraction protocols that may be used with non-invasively collected samples. In this paper, we describe and compare three methods of DNA extraction (DNeasy tissue kit, proteinaseK/TNES and Chelex-100) that use Odonate (Coenagrion mercuriale) exuviae as a non-invasive source of genetic material. DNA extracted from exuviae produced consistent genotypes at five polymorphic microsatellite loci for all of the samples processed using the DNeasy tissue kit and proteinase-K/TNES methods and 4 out of the 6 exuviae treated with Chelex-100. Exuviae offer an effective source of genetic material from endangered Odonates and also highly mobile species that are too difficult to catch in significant numbers. As such, we expect DNA extracted from exuviae to be widely applied to odonatological genetic research. INTRODUCTION DNA-based genetic analyses undoubtedly play an important role in many species' conservation plans (FRANKHAM et al., 2002; DESALLE & AMATO, 2004). Because of the inherent problems (i.e. time, expense and short-term bias) in directly tracking many species (SLATKIN, 1985), molecular markers offer a rapid and cost-effective method to indirectly estimate the extent of interpopulation dispersal and thus help define management units. With increasing degradation and fragmentation of freshwater habitats, it is perhaps not surprising that many Odonate populations/species are under threat from extinction (CORBET, 1999). For Odonates, a moleculargenetic appraisal of population connectivity and response to fragmentation would benefit the development of appropriate habitat-restoration/management plans. A reliable DNA extraction protocol is the foundation for any population-genetic investigation. For conservation purposes it is obviously essential that a non-destructive sampling regime is followed. Where possible, however, the ultimate goal for any conservation-genetic research should be the non-invasive isolation of genetic material. WATTS et al. (2001) and LODGE & FREELAND (2003) reported methods to obtain DNA from Odonate legs. Although leg samples may be removed from Odonates without measurably affecting their fitness (FINCKE & HADRYS, 2001; THOMPSON, unpublished data), this procedure is nonetheless invasive. In our experience, a rapid, large-scale genetic analysis of protected species can be hindered because of the need to acquire licences from several different government agencies. Rather than sampling adults directly, potential sources of genetic material are the shed exuviae that remain on aquatic vegetation after larval emergence. DNA from butterfly and honey bee 'exuviae' has been recovered by FEINSTEN (2004) and GREGORY & RINDERER (2004) respectively. The former study used a DNeasy Tissue Kit (Qiagen Inc.) to extract DNA while the latter authors followed a Chelex-100 protocol (see also WALSH et al., 1991). WATTS et al., (2001) and LODGE & FREELAND (2003) both employed Geneclean kits (Bio101) to extract DNA from Odonate legs, although to reduce cost and increase sample throughput we now use a proteinase-K/TNES method (SAMBROOK & RUSSELL, 2001) to extract DNA from Odonate leg samples. Here, we report the relative success of 3 simple methods DNeasy, Chelex-100 and proteinase-K/TNES of extracting DNA from Odonate (Coenagrion mercuriale) exuviae.
Paulo De Marco - One of the best experts on this subject based on the ideXlab platform.
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effects of human disturbance and riparian conditions on odonata insecta assemblages in eastern amazon basin streams
Limnologica, 2017Co-Authors: Jose Max Barbosa Oliveirajunior, Paulo De Marco, Karina Diassilva, Rafael P Leitao, Cecilia Gontijo Leal, Paulo Santos Pompeu, Toby Allan GardnerAbstract:Abstract Riparian vegetation is an important determinant of the physical, chemical, and biological condition of streams, and Odonates are useful indicators of riparian condition. To identify environmental factors that structure Odonata assemblages in tropical forest streams, we collected adult Odonate specimens and habitat data from 50 stream sites located in the Brazilian municipality of Paragominas (Para state). We collected 1769 specimens representing 11 families, 41 genera, and 97 species. Of these species, 56 were Zygoptera, and 41 were Anisoptera. Improved environmental condition was reflected in increased Zygoptera species richness and reduced Anisoptera species richness. Channel shading was strongly and positively related to Zygoptera richness, and negatively to Anisoptera richness. Zygoptera species richness, but not Anisoptera species richness, was related positively to bank angle, quantity of wood in the stream bed, electrical conductivity, and decreased water temperature. Altered riparian vegetation structure was the principal determinant of Odonate assemblage structure. Our results indicate that maintaining intact riparian vegetation is fundamental for conserving or re-establishing aquatic Odonate assemblage structure.
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Unprotecting the rare species: a niche-based gap analysis for Odonates in a core Cerrado area
Diversity and Distributions, 2011Co-Authors: Caroline C. Nóbrega, Paulo De MarcoAbstract:Aim We evaluated Odonata distribution data and predicted the compositional resemblance based on niche-based species distribution models to analyse the following questions: (1) How is estimated species richness distributed, and how can it be preserved under the actual network of conservation units (a gap analysis approach)? (2) How is the estimated Odonate beta diversity distributed, and is there a better distribution of conservation units (a priority setting approach)? (3) Is the probability of being under protection a function of the potential species range size? and (4) Will the current conservation network proposals protect Odonate taxa? Location Central Brazil in a core Cerrado area. Methods We generated Odonate species distribution predictions based on MaxEnt and maps derived from estimated species richness, beta diversity and gap analysis for all species predicted to occur in the study area. Then, we compared these maps with current conservation units, land-use patterns and proposals for the establishment of conservation units. Results Raw Odonate species records provided limited utility for setting conservation priorities without the use of niche-based models. However, area under the receiver operating curve (AUC) values were characterized by substantial variation that was related to the number of records. No current conservation units overlapped the areas with higher predicted richness and beta diversity, and in general, conservation units were not preserving restricted/rare species. There was a direct linear correlation between species range size and the proportion of its range protected in the current network of conservation units. Finally, we identified three areas with high Odonate beta diversity where conservationist actions should be implemented. Main conclusions Current conservation units and future suggested areas do not overlap regions with high conservation values for Odonates. Conservation units protect species at random, and the level of protection has a direct relationship with species range size; thus, wide-range species are expected to be more protected than restricted or threatened species.
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adult Odonate abundance and community assemblage measures as indicators of stream ecological integrity a case study
Ecological Indicators, 2010Co-Authors: Daniel Paiva Silva, Paulo De Marco, Daniela C ResendeAbstract:Abstract Water resources demand constant conservation actions due to several problems (e.g. riparian vegetation cut-off, construction of dams, acidification, sewage and pesticide spills) that degrade the aquatic systems worldwide and affect its physicochemical parameters and habitat characteristics. Odonata is a potential group of organisms that could indicate these habitat alterations once they have aquatic and terrestrial life forms. In this study, we tested the use of adult Odonate individual species and community assemblage measures to evaluate the effect of riparian vegetation cut-off and sewage discharges. The study was performed at Turvo Sujo River, in Vicosa, Southern Brazil. We selected twelve sites, six of them were upstream and six were downstream the city. Species abundance and species richness estimates of adult Odonates were performed on sunny days during summer and winter. We analyzed the goodness-of-fit of the species abundances to geometric and lognormal series. We also measured the Habitat Physical Integrity Score (HPIS), pasture and forest proportions and physicochemical water parameters at each site. Only few species were abundant in up- and downstream regions. Abundance of Argia modesta was higher at the upstream ( t = 3.188; df = 17; p = 0.005) than at the downstream region and this species is a potential habitat bioindicator organisms. Species richness was statistically different only in the wet season and species–abundance relations at the two regions fitted well to both geometric and lognormal series. The lack of riparian vegetation indicates a loss of habitat integrity and heterogeneity at Turvo Sujo River basin, which was mainly dominated by lake-dwelling Odonate species. Low species richness differences are caused by species pool biases toward those ones capable to survive at degraded ecosystems, suggesting that the effects of water parameters are much less important than a landscape dominated by pastures and practically without forests. We suggest the use of species–abundance models (like geometric and lognormal series) to determine the degree of impacts over a given community once they are simple models and can show intrinsic processes structuring communities.
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Efeito da alteração ambiental sobre comunidades de Odonata em riachos de Mata Atlântica de Minas Gerais, Brasil
Revista Brasileira de Zoologia, 2002Co-Authors: Patrícia Santos Ferreira-peruquetti, Paulo De MarcoAbstract:The effect of riparian deforestation and stream impoundments on an Odonate community was studied in areas of surviving Atlantic forest in Vicosa and in Rio Doce State Park (PERD), Marlieria, Minas Gerais, Brazil. During 1997 16 species of Libellulidae, 4 Coenagrionidae, 2 Gomphidae, 2 Calopterygidae, 1 Megapodagrionidae, 1 Aeshnidae and 3 Protoneuridae were collected. In Vicosa, the association of sampled Odonates with lotic or lentic systems, and in PERD for areas with or without riparian vegetation were compared. The results suggest that although overall Odonate taxonomic richness is high in areas without riparian vegetation. Likely, because productivity increase of such areas and its invasion by lentic Odonata species.
