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2. A new libelluloid dragonfly from late Paleocene deposits in Argentina (Odonata: Italoansida)
- Creator:
- Petrulevičius , Julián F. and Nel, André
- Type:
- article, model:article, and TEXT
- Subject:
- Odonata, libelluloid dragonfly, new genus and species, late Paleocene, Argentina, and South America
- Language:
- English
- Description:
- A new genus and species of "libelluloid" dragonfly, Jujusia maizgorda gen. n., sp. n., of the clade Italoansida Bechly, 1996, from the late Paleocene, Maíz Gordo Formation, north-western Argentina, is described. Its phylogenetic relationships within the clade Cavilabiata Bechly, 1996 are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Assessment of the quality of the terrestrial habitat of the threatened dragonfly, Sympetrum depressiusculum (Odonata: Libellulidae)
- Creator:
- Hykel, Michal, Filip Harabiš, and Aleš Dolný
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, vážky, ohrožené druhy, Odonata, endangered species, Libellulidae, Sympetrum depressiusculum, aquatic insect, habitat preference, habitat management, terrestrial environment, landscape heterogeneity, 2, and 59
- Language:
- English
- Description:
- The majority of the conservation strategies for threatened dragonflies are designed to protect only their aquatic habitats. Sympetrum depressiusculum is a species threatened not only by the destruction of its aquatic habitats but also by its association with a specific terrestrial environment. In this study, we aimed to identify the key elements of the terrestrial environment of adult S. depressiusculum. We used generalized linear mixed models to determine habitat preferences of adults and the particular features of habitat patches, such as vegetation cover, vegetation structure and the availability of potential prey. Our results indicate that S. depressiusculum adults preferred mainly riparian vegetation but beyond ponds they utilized only certain terrestrial habitats (abandoned fields, meadows, forest clearings). Adults responded positively to habitat patches with a high cover of vegetation and suitable vegetation structure. Adult abundance was affected also by the distance of patches from the natal site. In an agricultural landscape, the availability of such habitat patches may be limited and could influence the abundance and distribution of this species. We suggest that conservation efforts for this species should not only focus on the larval environment but also include suitable surrounding terrestrial habitats. Effective management around natal sites should concentrate on maintaining a heterogeneous landscape, which is extensively managed (e.g. leaving several fields fallow, maintaining managed hay meadows)., Michal Hykel, Filip Harabiš, Aleš Dolný., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Biometry of the large dragonfly Anax imperator (Odonata: Aeshnidae): a study of traits from larval development to adults
- Creator:
- Minot, Marceau, Le Gall, Mickaël , and Husté, Aurélie
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Odonata, Aeshnidae, Anax imperator, body length, body mass, larval rearing, sexual size dimorphism, and traits
- Language:
- English
- Description:
- Insect larval development affects adult traits but the biometric relationships are usually poorly understood, including large odonates. In this study, measurements of morphological traits of larvae, exuviae and adults of Anax imperator were recorded. They were used to investigate the effects of early development on adult morphology. Results showed an increase in larval length during the final instar and the length of its exuviae significantly exceeded that of the larva. Length and body mass of teneral adults were strongly related to the length of their exuviae. Adult males were significantly longer than adult females, while both had the same body mass at emergence. Length of teneral adults was negatively related to the date of emergence in both sexes. During maturation, body mass of males only increased slightly whereas that of females increased greatly. Mature specimens were also significantly longer than teneral individuals. Body mass of mature males and length of mature females were both associated with the date of capture. Wing length did not differ between sexes or from data available from Great Britain. This study underscores the importance of taking into account larval growth in order to better understand the adult traits of odonates.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Čtvrtstoletí průzkumu vážek na Podblanicku
- Creator:
- Lubomír Hanel
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, entomologie, vážky, entomology, Odonata, Podblanicko (Česko), Podblanicko (Czechia), 2, and 59
- Language:
- Czech
- Description:
- Lubomír Hanel.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Dragonflies and damselflies (Odonata) in urban ecosystems: a review
- Creator:
- Villalobos-Jiménez, Giovanna, Alison M. Dunn, and Hassall, Christopher
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, vážky, životní prostředí měst, velkoměsta, biodiverzita, bioindikátory, Odonata, urban ecology, cities, biodiversity, bioindicators, anthropogenic stressors, odonates, dragonflies, damselflies, ecotoxicology, behaviour, life history, phenotypic variation, ecological traps, 2, and 59
- Language:
- English
- Description:
- The expansion of urban areas is one of the most significant anthropogenic impacts on the natural landscape. Due to their sensitivity to stressors in both aquatic and terrestrial habitats, dragonflies and damselflies (the Odonata) may provide insights into the effects of urbanisation on biodiversity. However, while knowledge about the impacts of urbanisation on odonates is growing, there has not been a comprehensive review of this body of literature until now. This is the first systematic literature review conducted to evaluate both the quantity and topics of research conducted on odonates in urban ecosystems. From this research, 79 peer-reviewed papers were identified, the vast majority (89.87%) of which related to studies of changing patterns of biodiversity in urban odonate communities. From the papers regarding biodiversity changes, 31 were performed in an urban-rural gradient and 21 of these reported lower diversity towards built up city cores. Twelve of the cases of biodiversity loss were directly related to the concentrations of pollutants in the water. Other studies found higher concentrations of pollutants in odonates from built-up catchments and suggested that odonates such as Aeshna juncea and Platycnemis pennipes may be candidate indicators for particular contaminants. We conclude by identifying current research needs, which include the need for more studies regarding behavioural ecology and life-history traits in response to urbanisation, and a need to investigate the mechanisms behind diversity trends beyond pollution., Giovanna Villalobos-Jiménez, Alison M. Dunn, Christopher Hassall., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Ecological factors determining the density-distribution of Central European dragonflies (Odonata)
- Creator:
- Harabiš, Filip and Dolný, Aleš
- Type:
- article, model:article, and TEXT
- Subject:
- Habitat specificity, niche breath, Odonata, relative distribution, and dragonflies
- Language:
- English
- Description:
- Habitat specificity is the most important factor affecting the regional distribution of dragonflies. Nevertheless, species with the highest specificity are not always the scarcest. Several important determinants of dragonfly density-distribution relationships were identified. Altitude preference and altitude range are significantly associated with dragonfly distribution. Some of the species that are habitat specialists but occur over a wide range of altitudes should be classified as rare but not endangered. This very simple principle is based on the assumption that habitat specialists have a very limited number of suitable biotopes. Obviously, dragonflies with a marginal distribution prefer a narrow range of altitudes (especially in terms of temperature limitation) and biotopes (effect of biogeography, marginality). Surprisingly, there is no "critical" life stage that is significantly associated with the regional distribution of dragonflies, although most species spend most time in the larval stage. Knowledge of the dispersal ability of particular species is limited, although it could significantly affect species survival and distribution.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Emergence of the damselflies, Coenagrion mercuriale and Ceriagrion tenellum (Odonata: Coenagrionidae), at their northern range margins, in Britain
- Creator:
- Purse, Bethan V. and Thompson, David J.
- Type:
- article, model:article, and TEXT
- Subject:
- Odonata, emergence, seasonal regulation, Coenagrion mercuriale, and Ceriagrion tenellum
- Language:
- English
- Description:
- Emergence of Coenagrion mercuriale and Ceriagrion tenellum was examined in a mixed population at their northern range margin in Britain. Mortality at emergence was quantified in C. mercuriale. Consistent with their larval diapause characteristics, both species had an asynchronous emergence pattern, typical of "summer" species. Daily emergence of C. mercuriale was positively correlated with the duration of sunlight on the previous day (controlling for season) and its emergence period was found to be shorter than that observed in its core populations in Central and Mediterranean Europe. No differences were found between the patterns of emergence of the sexes in either species. Sex ratio at emergence differed significantly from 1:1 (at 1.35 : 1 - males : females) in C. mercuriale but not in Ceriagrion tenellum (at 1.04 : 1). Body size at emergence declined more steeply with time in females than in males of C. mercuriale because large size may confer a greater reproductive advantage in females (larger females may be more fecund) than males in non-territorial odonates. Percentage mortality of C. mercuriale at emergence was low (4.9% including deformed individuals), the main cause of mortality being deformity.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Fluctuating asymmetry, body size, reproductive period and life time mating success of males of Cercion lindeni (Odonata: Coenagrionidae)
- Creator:
- Carchini, Gianmaria, Di Domenico, Marco, Carla , Charotti, Flavia, and Pacione, Tiziana
- Type:
- article, model:article, and TEXT
- Subject:
- Life time mating success, body size, reproductive period, fluctuating asymmetry, Odonata, Coenagrionidae, and dragonfly
- Language:
- English
- Description:
- Mating success is linked to reproductive success in males, but parameters influencing it are poorly known. The relationships between lifetime mating success (LMS), fluctuating asymmetry (FA), body size (SIZE), reproductive period (RP) and emergence date (MD) of males of Cercion lindeni were investigated. Males were marked and photographed in their pre-reproductive period, and their matings monitored. RP was assumed to be the period between the MD and the last sighting of each individual. Three different FA measures and the size of each individual were determined. The results showed that the individuals not present at the pond during the reproductive period had a higher FA (but not for meristic characters) than those present. For those individuals actually involved in reproductive activity, LMS was only positively correlated with RP, which was negatively related with MD, and this with SIZE.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Genetic diversity, population structure and taxonomy of Calopteryx splendens (Odonata: Calopterygidae): An AFLP analysis
- Creator:
- Sadeghi, Saber, Kyndt, Tina, and Dumont, Henri
- Type:
- article, model:article, and TEXT
- Subject:
- Odonata, Calopteryx, AFLP, Genetic structure, diversity, and gene flow
- Language:
- English
- Description:
- Calopteryx splendens is a widely distributed palaearctic damselfly with a remarkably uniform morphology. Variation in the size and shape of the pigmented spot on the wing is the main diagnostic character used to discriminate subspecies across its huge geographic range. Here, AFLP analysis was used to assess the genetic structure and diversity of nine populations representing 3 putative subspecies and evaluate the pigment spot as a taxonomic marker. Genetic diversity was high, with the number of polymorphic loci per population ranging from 141 to 280 out of a total of 333 variable sites (42.3-84.1%) and Nei's gene diversity from 0.160 to 0.283 (overall 0.299). Overall population genetic differentiation (FST = 0.2766) suggests limited gene flow and adaptation to local environments. Restricted gene flow and genetic differentiation among populations are supported by significant FST estimates. High levels of gene flow (Nm >1) were only recorded among three Asian populations (Russia - Kazakhstan - Turkey). The patterns of genotypic diversity suggest that a given wing spot size and shape may arise from the hybridization of a limited number, possibly not more than four, ancestral gene pools in different ways and at different times. Clearly, the sample analyzed was not sufficient to capture all of the complex history of C. splendens, but sufficient to indicate the taxa ancilla, waterstoni, and orientalis possibly represent three of the four ancestral gene pools, and originated in western Asia. The origin of the fourth, xanthostoma, is the western Mediterranean.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
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