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242. Parasitism and migration in southern Palaearctic populations of the painted lady butterfly, Vanessa cardui (Lepidoptera: Nymphalidae)

Creator:
Stefanescu, Constanti, R. R. (Richard Robinson) Askew, Corbera, Jordi, and Shaw, Mark R.
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Lepidoptera, Nymphalidae, population dynamics, seasonal migration, enemy-free space, primary parasitoids, Cotesia vanessae, secondary parasitoids, 2, and 59
Language:
English
Description:
he painted lady butterfly (Vanessa cardui) (Lepidoptera: Nymphalidae: Nymphalinae) is well known for its seasonal long-distance migrations and for its dramatic population fluctuations between years. Although parasitism has occasionally been noted as an important mortality factor for this butterfly, no comprehensive study has quantified and compared its parasitoid complexes in different geographical areas or seasons. In 2009, a year when this butterfly was extraordinarily abundant in the western Palaearctic, we assessed the spatial and temporal variation in larval parasitism in central Morocco (late winter and autumn) and north-east Spain (spring and late summer). The primary parasitoids in the complexes comprised a few relatively specialized koinobionts that are a regular and important mortality factor in the host populations. However, there was a strong seasonal variation in the level of parasitism. In Spain percentage parasitism was more than four times higher in late summer than in spring (77.3% vs. 18%), while in Morocco it was five times higher by the end of winter than in the autumn (66.2% vs. 13.2%). In both regions the build up of parasitoid populations occurred after V. cardui had bred in the same general area over successive generations, and this may represent a selective force favouring seasonal migration to enemy-free space., Constanti Stefanescu ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

243. Pásemnička sladkovodní v České republice

Creator:
Jan Špaček
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, hmyz, bezobratlí, insects, invertebrates, 2, and 59
Language:
Czech
Description:
Pásemnička sladkovodní (Prostoma graecence) je málo známý, ale běžný vodní živočich. Žije na kamenech a vodních rostlinách v tekoucích i stojatých vodách, především v nižších polohách. Živí se drobnými planktonními a bentickými organismy. Na hlavě má 6 očních skvrn (mladší jedinci 4). Loví pomocí chobotku (proboscis), který obsahuje centrální trn s jedovou žlázou a po stranách 2 - 5 přídatných trnů. Tento orgán je typický pro pásnice (Nemertea)., The ribbon worm Prostoma graecense (Nemertea) is a little known but common water animal. It occurs on stones and plants in running and standing waters, mostly in the lowlands. It is a carnivore feeding on tiny planktonic and benthic animals. P. graecense has 6 black eyespots (young specimens have four) on the top of its head. The eversible proboscis is armed with one central stylet with a poison gland and paired pouches each containing two to five accessory stylets. The proboscis is a typical apparatus of ribbon worms, used for hunting., Jan Špaček., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

244. Patterns in diurnal co-occurrence in an assemblage of hoverflies (Diptera: Syrphidae)

Creator:
D´Amen, Manuela, Birtele, Daniele, Zappponi, Livia, and Hardersen, Sönke
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Diptera, Syrphidae, hoverflies, temporal structure, interspecific relations, null models, 2, and 59
Language:
English
Description:
In this study we analyzed the inter-specific relationships in assemblages of syrphids at a site in northern Italy in order to determine whether there are patterns in diurnal co-occurrence. We adopted a null model approach and calculated two co-occurrence metrics, the C-score and variance ratio (V-ratio), both for the total catch and of the morning (8:00–13:00) and afternoon (13:00–18:00) catches separately, and for males and females. We recorded discordant species richness, abundance and co-occurrence patterns in the samples collected. Higher species richness and abundance were recorded in the morning, when the assemblage had an aggregated structure, which agrees with previous findings on communities of invertebrate primary consumers. A segregated pattern of co-occurrence was recorded in the afternoon, when fewer species and individuals were collected. The pattern recorded is likely to be caused by a number of factors, such as a greater availability of food in the morning, prevalence of hot and dry conditions in the early afternoon, which are unfavourable for hoverflies, and possibly competition with other pollinators. Our results indicate that restricting community studies to a particular time of day will result in certain species and/or species interactions not being recorded., Manuela D´Amen ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

245. Patterns in the diversity of dragonflies (Odonata) in cities across Central Europe

Creator:
Willigalla, Christoph and Fartmann, Thomas
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, donata, climate change, environmental gradient, species richness, temperature, urbanisation, 2, and 59
Language:
English
Description:
1_Urbanisation is an important cause of species extinctions. Although urban water systems are also highly modified, studies on aquatic or semi-aquatic organisms are rare. The aim of this study is to identify the factors that determine species richness of Odonata in 22 Central European cities and along an urban-rural gradient within six of them. With 64 indigenous species in total and an average of 33 species per city, the species richness of Odonata in Central European cities is comparatively high. A generalised linear model indicates that species richness is positively related to city area. Additional predictors are climatic variables (temperature amplitude, sunshine duration and July temperature) and the year last studied. Since most cities are usually located in areas with naturally high habitat heterogeneity, we assume that cities should be naturally rich in dragonflies. The role of city area as a surrogate for habitat and structural richness most likely explains why it is strongly associated with Odonata species richness. The relationship between species richness and the climatic variables probably reflects that Odonata species richness in Central Europe is limited by warm and sunny conditions more than by availability of water. The temporal effect (the year last studied) on species richness is likely to be a consequence of the recent increase in Mediterranean species associated with global warming. Urbanisation clearly has an adverse effect on the species diversity of Odonata. Species richness increases along a gradient from the centre of a city to the rural area and is significantly highest in rural areas. This pattern probably reflects a gradient of increasing habitat quality from the centre of cities to rural areas. Moreover, the number of water bodies is generally very low in the city centres., 2_Based on our results, we make recommendations for increasing the abundance and number of species of dragonflies in cities., Christoph Willigalla, Thomas Farmann., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

246. Patterns of hind-wing degeneration in Japanese riffle beetles (Coleoptera: Elmidae)

Creator:
Masakazu Hayashi, Song, Simon D., and Sota, Teiji
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Coleoptera, Elmidae, aquatic beetle, body shape, body size, dimorphism, flightlessness, 2, and 59
Language:
English
Description:
We conducted a molecular phylogenetic analysis based on mitochondrial cytochrome oxidase subunit I and nuclear 28S rRNA gene sequences of species of Japanese elmids (23 species from 12 genera) and examined the hind-wings of 24 species in order to determine the incidence of hind-wing degeneration among species and the presence of dimorphic species with respect to hind-wing degeneration. Based on the molecular phylogenetic analysis, we determined that the previously separated winged and wingless species, Stenelmis vulgaris and S. miyamotoi, and Leptelmis gracilis and L. parallela, are two forms of the same species. Of the 24 species whose hind wings were studied, we found apterous (3 species of Zaitzeviaria), brachypterous (2 species of each of Optioservus and Paramacronychus) and dimorphic species (2 species as above) in separate clades of the phylogeny. These were the smallest or medium-sized species. Dimorphic species occurred in mid- to downstream areas and used reeds and wood as substrates. The percentage of species with hind-wing degeneration (wingless or dimorphic) was high among the species (29%) studied compared to the perceived percentage for temperate beetles (<10%). Thus, we found that the degeneration of hind wings has occurred repeatedly in these elmid species. However, we identified only ambiguous habitat and life history correlates of hind-wing degeneration, and the adaptive significance of hind-wing degeneration in these species of elmids remains unclear., Masakazu Hayashi, Simon D. Song, Teiji Sota., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

248. Periods of dormancy and cohort-splitting in the millipede Polydesmus angustus (Diplopoda: Polydesmidae)

Creator:
David, Jean-François, Celerier, Marie-Louise, and Geoffroy, Jean-Jacques
Format:
print, text, and regular print
Type:
article, bibliography, conference publication, model:article, and TEXT
Subject:
Third European Workshop of Invertebrate Ecophysiology (1998 : Birmingham, Česko), zoologie, fyziologie živočichů, ekofyziologie, hmyz, Diplopoda, Polydesmus angustus, životní cyklus, reprodukční dormance, diapauza, sezónní vlivy, 591.5, 061.3, and 595.2/.7
Language:
English
Description:
First stadium juveniles of P. angustus were reared under controlled seasonal conditions to maturity, reproduction and death. Individuals born in any one breeding season either had a 1-year or a 2-year life cycle (cohort-splitting). The life cycle was annual for individuals born in the first part of the breeding season (May-August), but became biennial for those born later (August-October). Two phenomena were involved: (1) Only individuals reaching the penultimate stadium (stadium VII) before a critical period at the end of spring could become adult in the breeding season following that of their birth. After this time, stadium VII individuals entered into aestivation and only became adult in the second autumn after their birth. (2) Females becoming adult in autumn entered reproductive dormancy and only laid eggs in the following spring. Overall, individuals born at the start of the breeding season easily reached stadium VII before the critical period and were able to breed at I year, whereas individuals born at the end of the breeding season reached stadium VII after the critical period, then had two consecutive periods of dormancy and only bred at 2 years age. Individuals from the same nest born in the middle of the breeding season (August) could have either annual or biennial life cycles, depending on whether they reached stadium VII before or during aestivation. The environmental factors capable of triggering aestivation in subadults and reproductive dormancy in autumn-maturing females are discussed., Jean-Francois David, Marie-Louise Celerier, Jean-Jacques Geoffroy, and Lit
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

250. Phylogenetic relatedness of Erebia medusa and E. epipsodea (Lepidoptera: Nymphalidae) confirmed

Creator:
Šemeláková, Martina, Peter Pristaš, and Panigaj, Lubomír
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Lepidoptera, Nymphalidae, Erebia medusa, E. epipsodea, mtDNA, COI, ND1, 2, and 59
Language:
English
Description:
The extensive genus Erebia is divided into several groups of species according to phylogenetic relatedness. The species Erebia medusa was assigned to the medusa group and E. epipsodea to the alberganus group. A detailed study of the morphology of their copulatory organs indicated that these species are closely related and based on this E. epipsodea was transferred to the medusa group. Phylogenetic analyses of the gene sequences of mitochondrial cytochrome C oxidase subunit I (COI) and mitochondrial NADH dehydrogenase subunit 1 (ND1) confirm that E. medusa and E. epipsodea are closely related. A possible scenario is that the North American species, E. episodea, evolved after exclusion/isolation from E. medusa, whose current centre of distribution is in Europe., Martina Šemeláková, Peter Pristaš, Lubomír Panigaj., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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