Invertebrate diversity has rapidly declined throughout Europe during the last century. Various reasons for this decrease have been proposed including human induced factors like climate change. Temperature changes alter distributions and occurrences of butterflies by determining habitat conditions at different scales. We evaluated changes in the composition of butterfly communities recorded at nine areas of fallow ground in south-western Germany in 1973, 1986, 2010 and 2012 using Pollard’s transect technique. To demonstrate the importance of climatic changes in affecting butterfly communities, we calculated the community temperature index (CTI) for each butterfly community in each year. Although they increased slightly, the CTI-values did not match the temperature trends recorded in the study region. However, the reduction in the standard deviations of the CTIs over time is reflected in the marked loss of cold- and warm-adapted species due to their inability to cope with temperature and land-use induced habitat changes. Results of our butterfly surveys indicate a marked decline in species richness and striking changes in the composition of the butterfly communities studied. This trend was most pronounced for habitat specialists, thus mirroring a depletion in trait diversity. Our results indicate that, in the course of large-scale anthropogenic changes, habitat degradation at smaller scales will continuously lead to the replacement of habitat specialists by ubiquitous species., Katharina J. Filz ... [et al.]., and Obsahuje seznam literatury
1_The adult demographic parameters, mobility, nectar choice and how the spatial distribution of males and females of Z. polyxena is affected by the distribution and abundance of host-plants, and adults of the opposite sex was studied in a population of this species inhabiting a dense network of permanent habitats (totalling 8.7 ha). The population size was estimated to be ca. 300 individuals. The average adult lifespan was 4.4 days and the maximum 23 (male) and 20 (female) days. The capture probability was higher for males than females due to the more conspicuous behaviour and bounded area of activity of males. A slow increase was followed by a slow decrease in the sex specific parabolic recruitment curve, indicating slight protandry and long emergence period, probably due to habitat heterogeneity. The spatial distribution of host plants (Aristolochia lutea) is the key factor determining the spatial distribution of adults. There was a strong positive correlation between male and female density at each patch, both of which were dependent on the cover of host plants growing in sunny conditions. In searching for A. lutea plants suitable for oviposition, females fly greater distances and move more frequently between patches than males. The size, shape and orientation of the male home range were influenced by the size, shape and orientation of stands of host-plants in sunny positions, but not by patch area. Such adult fidelity to stands of host-plants in sunny positions indicates that the spatial distributions of oviposition sites, mate-locating sites and larval habitats of Z. polyxena overlap. The better statistical fit and much lower probabilities for long-distance movements generated by a negative exponential function than an inverse power function are probably due to the small size and high habitat connectivity of the site studied. Adults were opportunistic in their use of nectar plants., 2_Traditional management is the key factor for maintaining permanent habitats for this species in a grassland biotope., Tatjana Čelik., and Obsahuje seznam literatury
The relationship between species richness of plants and animals and altitude can be either hump-shaped, a monotonic decrease or increase. In this study the altitudinal distribution of moths on one of the highest mountains in South Korea was investigated. Moths were captured using a UV-light trap from May to October in 2007 and 2008. This revealed that the relationship between the total numbers of moth species and individuals and altitude is hump-shaped. A significant relationship was also recorded between the size of the area at each altitude and moth abundance and richness. However, the evenness index yielded a consistent decrease with increase in altitude because of the dominance of few species at high altitudes. Non-metric multidimensional scaling identified two major axes for the moth assemblage on Mount Jirisan. The correlations between the axes and variables demonstrated that the first axis was strongly correlated with altitude and aspect and the second axis with forest and site location.
Adults of the wingless bagworm moth, Eumeta variegata, show remarkable sexual dimorphism. Final-instar larvae of the male have invaginated wing discs, whereas those of the female are rudimentary. To determine the best method for culturing the wing discs of E. variegata, which in both sexes are attached to the larval integument, two methods of culturing the larval wing discs are compared. Initially, a stationary culture was used. In these cultures necrotic cells and degeneration of wing discs of males were sporadically observed. By contrast, many small vacuoles were observed in the female wing rudiment under these conditions. In order to overcome some of the problems associated with stationary culture, rotating culture was used and resulted in the wing discs of males and females remaining in good condition. A histological analysis revealed that the wing disc morphology was normal when they were cultured in this way. These results indicate that rotating the culture medium is the better procedure for studying the action of hormones on the differentiation and metamorphosis of reduced wing rudiments in E. variegata.
The feeding behaviour of specialist butterflies may be affected by the mechanical and chemical characteristics of the tissues of their host-plants. Larvae of the butterfly, Battus polydamas archidamas feed only on Aristolochia chilensis, which contains aristolochic acids. We studied the oviposition pattern of adults and the foraging of larvae of B. polydamas archidamas over time in relation to variations in hardness of the substrate and concentration of aristolochic acids in different plant tissues. We further tested the effect of two artificial diets containing different concentrations of aristolochic acids on larval performance. B. polydamas archidamas oviposited mostly on young leaves and the larvae fed on this tissue until the second instar. Third instar larvae fed also on mature leaves and fourth and higher instars fed also on stems. Young leaves are softer and contain higher concentrations of aristolochic acids than mature leaves, and stems are both harder and contain a high concentration of aristolochic acids. Larvae reared on artificial diets containing a high concentration of aristolochic acids suffered less mortality and were heavier than those reared on a diet with a lower concentration of aristolochic acids, which suggests they are phagostimulatory. A strategy of host use regulated by aristolochic acid content and tissue hardness is discussed.
Moths are frequently used as indicators of biodiversity or habitat quality. Light traps are the most effective and widely used method for gathering data on moth communities. Knowing the distance from which moths are drawn to a light trap is therefore essential for the ecological interpretation of such data. Two community-wide mark-release-recapture experiments were carried out in forest habitats in central Europe in order to investigate whether the percentage of marked moths recaptured at weak artificial light sources (2 × 15 W UV-light tubes) is dependent on the distance they were released from the light source. Altogether 2,331 moths belonging to 167 species were caught at light traps and released at distances of 2–100 m. Of these moths 313 returned to the light trap within 5 min of release. Percentage recapture was generally low (gross rate 13.4%) and strongly decreased with increase in the distance at which they were released. Percentage recapture was not significantly affected by ambient temperature or the sex of the moths. Only for the Geometroidea was the percentage recaptured slightly greater for the larger species. We found no significant differences between moth super-families with regard to the distance dependence of their attraction to light. Our data confirm that the radius of attraction of low powered light traps for moths is very small often even below 10 m. Thus, moths are good indicators of habitat quality and fragmentation as they are rarely attracted from distant habitats to such light traps., Christine Truxa, Konrad Fiedler., and Obsahuje seznam literatury
The plant stress and plant vigour hypotheses are competing paradigms pertaining to the preference and performance of herbivorous insects on their host plants. Tests of these hypotheses ideally require detailed information on aspects of soil nutrition, foliar nutrient levels and parameters of herbivore fitness, but such studies are uncommon. These hypotheses were tested using the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), reared on its host plant, Brassica napus (L.), grown in an experimental system of five nutrient regimes. Different levels of fertilizer treatments significantly affected the nutrient content of B. napus foliage and this in turn affected the preference and performance of P. xylostella. Ovipositing females discriminated among host plants grown in soils subjected to different fertilizer treatments and selected plants on which pre-imaginal survival was highest, development fastest and longevity of the next generation of adults the longest, even when food was scarce. Plants subjected to herbivory by P. xylostella responded by producing elevated levels of some nutrients (e.g., sulphur), but other nutrient levels declined in infested leaves (e.g., nitrogen). Regardless of the rate of fertilizer application, plants compensated for herbivory by increasing root mass compared to un-infested control plants; plants grown in soils receiving the optimum quantity of fertilizer developed the most robust root systems when infested. The plant stress and the plant vigour hypotheses are likely to be at the opposite ends of a continuum of responses between insects and their host plants. Our investigations indicate a complex set of interactions involving both bottom-up and top-down effects, which interact to affect host plant quality, oviposition site selection by female herbivores and the fitness of their offspring.
We used butterfly assemblages to evaluate the ecological value of habitat mosaics within garrigue ecosystems in Cyprus. To understand the importance of the local plant communities for Cypriot butterflies, five plots in each of two habitat types (grass-dominated or shrub-dominated) were surveyed weekly for a period of five months in order to assess the abundance, species richness and diversity of butterflies. A total of 810 butterflies of 16 species were recorded. Indices of butterfly diversity, calculated across the whole season, were similar between grassland and shrubland dominated mosaics. However, species richness of all butterflies was consistently higher in grassland dominated mosaics throughout the whole season. The peak abundance of all butterfly species occurred during mid-season (late April - early May), with similar numbers observed in both habitat types. However, a greater abundance was observed during early and late season in grassland patches. The abundance of endemic species (Maniola cypricola, Hipparchia cypriensis, Glaucopsyche paphos) peaked earlier in the season in shrubland patches, but was higher in grassland patches in late season. This difference in seasonal timing of endemic abundance was dominated by the seasonal dynamics of M. cypricola. These results suggest that, while garrigue is characterised by its shrub flora, management to maintain a mosaic of grassland and shrubland could act to maximise the abundance and richness of indicator species groups of conservation importance. and Özge Özden, David J. Hodgson.
Geographic isolation, altitude, climate, landscape and habitat are significant predictors of butterfly diversity in mountain ecosystems. Their diversity and its dependence on altitude, aspect (compass bearing) and biogeographic characteristics of the butterflies were surveyed on the karst mountain Biokovo in southern Croatia. The results affirm that there is a high diversity of butterflies in the study area and the species composition and biogeographic elements are more dependent on altitude than aspect of the mountain. The present study indicates that climate, relief and habitat preferences strongly influence the biogeographic features of species and the relationship between species richness per site and altitude, aspect and the altitude-aspect interaction. and Iva Mihoci, Vladimir Hršak, Mladen Kučinić, Vlatka Mičetić Stanković, Antun Delić, Nikola Tvrtković.
Currently it remains difficult to obtain robust microsatellite markers for Lepidoptera. In an attempt to overcome the problems associated with developing microsatellite markers for this insect order we combined (i) biotin-enrichment protocol, (ii) next generation pyrosequencing (through 454 GS-FLX Titanium technology) and (iii) the use of individuals collected from eight geographically distant European populations representing three subspecies of Euphydryas aurinia. Out of 96 stringently designed primer pairs, 12 polymorphic microsatellite loci amplified without obvious evidence of null alleles in eight individuals from different subspecies. Between five and seven of these loci showed full within population applicability and three revealed to be robust and transferable between populations and sub-species, providing a first step towards the development of a valuable and robust tool for studying conservation issues and evolution in E. aurinia populations. Nevertheless, as in most studies dealing with Lepidoptera microsatellites, null alleles were detected in most of the developed markers. Our results emphasize the need for further research in order to better understand the complex evolution and organization of Lepidopteran genomes. and Melthide Sinama, Vincent Dubut, Caroline Costedoat, André Gilles, Marius Junker, Thibaut Malausa, Jean-François Martin, Gabriel Nève, Nicolas Pech, Thomas Schmitt, Marie Zimmermann, Emese Meglécz.