« Previous |
1 - 10 of 81
|
Next »
Number of results to display per page
Search Results
2. A review of the European species of Phradis (Hymenoptera: Ichneumonidae: Tersilochinae), with a description of a new species from Spain
- Creator:
- Khalaim, Andrey I. , Bordera, Santiago , and Rodríguez-Berrío, Alexander
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera, Ichneumonidae, Tersilochinae, Phradis, new species, taxonomy, key, Europe, and Spain
- Language:
- English
- Description:
- European species of the genus Phradis Förster, 1869 are reviewed. A new species from Spain, Phradis mediterraneus sp. n., is described and illustrated. A key to all 24 European species and data on distribution and biology of these species are provided.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Abundance and host associations of parasitoids attacking frugivorous drosophilids on Iriomote-jima, a subtropical island of Japan
- Creator:
- Novkovic, Biljana, Oikawa, Ayako, Murata, Yusuke, Mitsui, Hideyuki, and Kimura, Masahito T.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Braconidae, Asobara, Figitidae, Leptopilina, Diptera, Drosophilidae, Drosophila, parasitoid, host association, resistance, virulence, 2, and 59
- Language:
- English
- Description:
- To understand the factors governing the diversity, abundance and host associations of parasitoids attacking frugivorous drosophilid flies on Iriomote-jima, a subtropical island of Japan, we monitored parasitism on several occasions over the period 2003–2009. Fifteen drosophilid and 12 parasitoid species were recorded. Three species of Drosophila, D. bipectinata, D. albomicans and D. takahashii, bred abundantly in banana baits, though their abundance varied between years and seasons. Frequent parasitoid species were Asobara japonica, A. pleuralis (Braconidae), Leptopilina ryukyuensis and L. pacifica (Figitidae). L. victoriae was recorded only in December 2003. In addition, host acceptance and host suitability of the four most frequently recorded parasitoid species were studied in the laboratory. Most parasitoid and drosophilid species showed species-specific associations with more than one antagonist species, suggesting that they have been subjected to complex coevolutionary interactions. In addition, host range of most of the parasitoid species included one of the three major Drosophila species, suggesting that the abundance of potential hosts is one of the factors determining the evolution of parasitoid host use., Biljan Novkovic ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Acceptance of two native myrmecophilous species, Platyarthrus hoffmannseggii (Isopoda: Oniscidea) and Cyphoderus albinus (Collembola: Cyphoderidae) by the introduced invasive garden ant Lasius neglectus (Hymenoptera: Formicidae) in Belgium
- Creator:
- Dekoninck, Wouter, Lock, Koen, and Janssens, Frans
- Type:
- article, model:article, and TEXT
- Subject:
- Isopoda, Oniscidea, Collembola, Cyphoderidae, Hymenoptera, Formicidae, Lasius neglectus, myrmecophilous species, invasive species, acceptance, Cyphoderus albinus, and Platyarthrus hoffmannseggii
- Language:
- English
- Description:
- The myrmecophilous isopod Platyarthrus hoffmannseggii Brandt, 1833 and the myrmecophilous springtail Cyphoderus albinus Nicolet, 1842 are commonly found in nests of a wide range of ant species in Belgium. Here we report the first record of both myrmecophiles in nests of the invasive garden ant Lasius neglectus in the Citadelpark of Ghent, Belgium. Platyarthrus hoffmannseggii was found in two of the Lasius neglectus nests studied. In one of the two C. albinus was also discovered. In the localities where the invasive garden ant Lasius neglectus was introduced, as is also the case in the Citadelpark in Ghent, it out-competes all native ant species. This ant has a dramatic effect on the local native ant fauna. However, some of the myrmecophilous species associated with the native ant-fauna are less threatened as they are accepted by this invasive garden ant.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Ant communities (Hymenoptera: Formicidae) of Flemish (north Belgium) wet heathlands, a declining habitat in Europe
- Creator:
- Maes, Dirk, Van Dyck, Hans, Vanreusel, Wouter, and Cortens, Joeri
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera, Formicidae, ants, wet heathland, diversity, between year fluctuation, conservation, sampling methodology, and Belgium
- Language:
- English
- Description:
- During a survey of 23 wet heathland sites in Flanders (north Belgium) in 1999 and 2000, using both manual nest searching and pitfall traps as sampling techniques, we found 28 ant species. One species (Myrmica lonae) was new to the Belgian fauna and several rare species were encountered. Three ecological groups could be distinguished based on soil preference: the first group of species was characteristic of sandy soil, the second contained species that were more numerous on peat soil (with Sphagnum spp.), and the third group of species had no soil preference. Ant nest numbers increased strongly between 1999 and 2000, especially on the plots that were inundated during the winter of 1999-2000, but the number of ant species did not differ significantly between years. Ant nest density showed an optimum at a Purple Moor-grass (Molinia caerulea) cover of about 45%; the number of species did not show such an optimum. Pitfall traps yielded more species than manual nest searching; in particular temporary social parasites, species with a large foraging range and winged females from the surrounding habitats were missed by the latter technique. Finally, we give some recommendations for the conservation of, and suitable management measures for, ants on wet heathland.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Ant diversity (Hymenoptera: Formicidae) and predation by ants on the different stages of the sugarcane borer life cycle Diatraea saccharalis (Lepidoptera: Crambidae)
- Creator:
- Oliveira, R.D.F, Almeida, L.C.D., Souza, D.R.D., Munhae, C.B., Bueno, O.C., and Morini, M.S.C
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Hymenoptera, Formicidae, biological control, Diatraea saccharalis, mechanical cultivation, 2, and 59
- Language:
- English
- Description:
- The sugarcane borer Diatraea saccharalis is an important pest of sugarcane and ants are one of its main predators. The practice of burning sugarcane straw in situ after harvest has been gradually replaced in Brazil by other practices. However, it is unknown whether ants can control the abundance of this borer in the presence of straw. In this study, we assessed the diversity and species composition of ants attacking different stages of the pest’s life cycle. Specifically, we asked whether the species richness and abundance of ants varies during the course of day and a year. We established one-hectare plots at random locations in a sugarcane plantation. Once a month, we collected 20 samples of each stage of the D. saccharalis life cycle and randomly distributed these samples as bait on plants spaced 20 m apart within a plot. Ants were collected daily in the morning and afternoon over a period of 12 months. We identified several aspects of ant feeding behaviour that may affect their biological control of the borer: (1) the greatest number of ants were collected from baits consisting of the immature stages of the sugarcane borer, (2) ants were most active in the morning and (3) their activity varied from month to month. Solenopsis saevissima and morphotypes of Crematogaster sp.7 and Pheidole sp.35 are potentially important predators of borers in sugarcane crops in which the straw is not burnt., Roseli de Fatima de Oliveira ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Anthropogenic induced changes in nesting densities of the dune-specialised digger wasp Bembix rostrata (Hymenoptera: Sphecidae)
- Creator:
- Bonte, Dries
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera, Sphecidae, Bembix rostrata, disturbance, population density, recreation, and trampling
- Language:
- English
- Description:
- Data on nesting densities of Bembix rostrata, a digger wasp inhabiting dynamic coastal dunes, were used to document the detrimental effects of trampling by cattle and vacationers. Both types of disturbance resulted in similar sand displacement and prey availability. Nesting densities of Europe's largest digger wasp declined dramatically with increasing trampling, probably below the critical population size. Hence, additional human disturbance, although resulting in similar environmental conditions compared to natural disturbance, significantly affected local population sizes. As a result, anthropogenic has to be avoided disturbance in order to restore or conserve natural dynamics and efforts to restore natural dynamics in a more natural way should be promoted. Although this is here only documented for one, large specialised invertebrate, the application of traditional management techniques, such as grazing by large herbivores, within newly evolved landscapes may introduce new pressures that affect pre-adapted species to natural disturbances negatively within short time spans.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. Arrhythmic adult ecdysis but rhythmic emergence from the host chorion in Trichogramma embryophagum (Hymenoptera: Trichogrammatidae)
- Creator:
- Reznik, Sergey Ya., Voinovich, Natalia D., Vaghina, Nina P., and Karpova , Svetlana G.
- Type:
- article, model:article, and TEXT
- Subject:
- Parasitoids, Hymenoptera, Trichogramma, circadian rhythms, photoperiod, pupal-adult ecdysis, and adult emergence
- Language:
- English
- Description:
- In many insect species with a pupa covered by various "shells" (puparium, host remains, etc.) pupal-adult ecdysis and emergence to the open air represent two discrete steps. However, in Trichogramma, as well as in other insect parasitoids, these two processes have never been studied separately. We investigated the temporal pattern of pupal-adult ecdysis and of adult emergence from the host chorion in Trichogramma embryophagum Hartig (Hymenoptera: Trichogrammatidae) in laboratory conditions (12L : 12D, 20°C). Adult ecdysis was arrhythmic, while adult emergence showed a strong rhythmicity. The time lag between ecdysis and emergence varied from one to almost two days, depending on the circadian time of the ecdysis. The proportion of ecdysed adults that stayed in the host chorion ranged up to 60% (just before the highest peak of emergence). The cumulative percentage of ecdysed adults gradually increased with time, independently of whether the light was turned on in accordance with the entrained circadian rhythm or 4 h earlier. This arrhythmic ecdysis could be explained by the fact that the ecdysed adults get into a well protected space inside the host chorion and the timing of this event is adaptively neutral.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Augmentation of managed populations of Osmia cornuta and O. rufa (Hymenoptera: Megachilidae) in Southeastern Europe
- Creator:
- Krunić, Miloje and Stanisavljević, Ljubiša
- Type:
- article, model:article, and TEXT
- Subject:
- Hymenoptera, Megachilidae, orchard bees, pollination, Osmia cornuta, Osmia rufa, augmentation, soil watering, and Serbia
- Language:
- English
- Description:
- We describe augmentation of managed populations of Osmia cornuta and O. rufa in the vicinity of Belgrade (Serbia). Annual augmentation of O. cornuta populations was more than five-fold during the six years of our study. This was achieved by watering the soil near the Osmia augmentation shelters used for nest building. However, populations of O. rufa under the same treatment only doubled annually. Data are also presented on sex ratios in these managed populations, the sex ratio being an important factor in increasing population numbers and raising pollination efficacy. Sex ratio values (♂ : ♀) varied from 1.46 : 1 to 3.22 : 1 in the populations of O. cornuta and from 1.35 : 1 to 2.68 : 1 in those of O. rufa.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Bait visitation by Formica lemani (Hymenoptera: Fomicidae) indicates shortage of carbohydrates in alpine grasslands
- Creator:
- Guariento, Elia, Martini, Jan, and Konrad Fiedler
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- blanokřídlí, Formica, mravencovití, Hymenoptera, ants, Formicidae, nutritional ecology, baits, nutrient limitation, alpine ecology, trophic position, 2, and 59
- Language:
- English
- Description:
- Insights can be gained by analysing the feeding decisions of animals in terms of nutrient demands at a species or community level. Using carbohydrate and protein food baits, resource use and food preferences of Formica (Serviformica) lemani were determined at nine locations situated at different altitudes (1875 to 2400 m a.s.l.) in the alpine grassland belt above the tree line in Austria and northern Italy. F. lemani is the most common species of ant in this habitat. Sucrose baits placed around ant colonies were visited by significantly (3.9 times) more workers than protein baits. This indicates that sources of sugar (carbohydrate) are in short supply in the alpine zone, whereas availability of prey items appears to be less constraining. Overall, we recorded a decrease in the incidence of visits to baits from low (31.9% baits attracting ants at least once) to high altitudes (16.7%). Foraging ants never visited 51.5% of the baits exposed for periods of 75 min. This indicates that with increasing altitude competition for food among ant colonies becomes less intense in alpine grassland ant communities., Elia Guariento, Jan Martini, Konrad Fiedler., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public