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12. Harmonia axyridis (Coleoptera: Coccinellidae): Smelling the rat in native ladybird declines
- Creator:
- John J. Sloggett
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, slunéčko východní, urbanizace, beetles, Coccinellidae, Harmonia axyridis, urbanization, Coleoptera, Adalia bipunctata, alien invasive, habitat compression, native species decline, 2, and 59
- Language:
- English
- Description:
- In the last two decades a huge amount of research has focused on the invasive harlequin ladybird, Harmonia axyridis, particularly on potential or actual deleterious effects that have arisen after it has colonised new regions. A focus of this work has been real or anticipated declines in native ladybird abundance since the introduction of H. axyridis, for which it is deemed responsible. Scientists have generally painted a very bleak picture of the effects of H. axyridis on native species: in this paper I argue that the picture painted is often too bleak. I use the case of the 2-spot ladybird, Adalia bipunctata, the species most often invoked as threatened by H. axyridis, to illustrate my point. While there is little question that H. axyridis has led to a decline in A. bipunctata populations in Europe, it seems likely that prior to the invasive ladybird's arrival A. bipunctata occurred in artificially high numbers in the urban environments in which it was typically studied. Pollution in towns and cities led to enhanced numbers of prey aphids on plants there which initially favoured A. bipunctata, and later H. axyridis. Thus one species, A. bipunctata, that has benefitted from an association with humans has been replaced by another, H. axyridis, just as brown rats replaced black rats in Europe and North America. Viewed with a longer perspective, A. bipunctata has more likely declined back to pre-industrial levels: the artificially high level from which it has declined recently was not a 'natural' one, and thus its decline from this level does not imply that it is now threatened or endangered. More broadly, we need a wider perspective, encompassing other ladybirds, longer timeframes and better comparisons with other (non-ladybird) invasive species to more clearly assess whether H. axyridis really poses as much of a threat as is often proposed., John J. Sloggett., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
13. Host condition effects upon Agrilus planipennis (Coleoptera: Buprestidae) captures on decoy-baited branch traps
- Creator:
- Domingue, Michael J., Berkebile, Jennifer, Steiner, Kim, Hall, Loyal P., Cloonan, Kevin R., Lance, David, and Baker, Thomas C.
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, krascovití, polník, fenomenologie, beetles, Buprestidae, Agrilus, phenomenology, Coleoptera, Agrilus planipennis, emerald ash borer, exit hole, flight, invasive species, mate search, 2, and 59
- Language:
- English
- Description:
- We deployed branch traps in an ash (Fraxinus) plantation to investigate how Agrilus planipennis behavior is associated with Fraxinus pennsylvanica condition and dispersal patterns. Data were collected from traps with or without the presence of beetle visual decoys, and from a yearly survey of exit holes. The traps were placed on trees that were either clearly declining, with most foliage arising from epicormic sprouting, or on apparently healthy trees, with little evidence of damage or decline. We calculated correlations of exit holes among neighboring tree rings and also between exit holes and male trap captures. The damaged trees the traps were hung upon had more cumulative exit holes observed than the corresponding healthy trees. However, there was otherwise no evidence that the experiment was biased by differences in exit hole patterns of the surrounding trees. Male captures were greater on decoy-baited traps than controls and this decoy effect was most clearly apparent late in the season when traps were placed on healthy trees. There were also patterns of correlations between male captures and exit hole numbers that may be indicative of short-range mate finding-and dispersal behaviors. Female captures were sparser, but were positively affected by decoys on healthy and declining trees early in the season. Thus, the results suggest that the placement of such traps on healthier trees will maximize detection, and the branch traps also show promise for further use in dispersal studies., Michael J. Domingue, Jennifer Berkebile, Kim Steiner, Loyal P. Hall, Kevin R. Cloonan, David Lance, Thomas C. Baker., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14. Isolation and characterization of novel microsatellite loci in the genome of the dragonhead sap beetle Thymogethes norvegicus (Coleoptera: Nitidulidae)
- Creator:
- Kleven, Oddmund and Endrestøl, Anders
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, lesknáčkovití, beetles, Nitidulidae, Coleoptera, Thymogethes norvegicus, microsatellite loci, genetic diversity, 2, and 59
- Language:
- English
- Description:
- Here we describe 16 novel microsatellite loci in the genome of the dragonhead sap beetle Thymogethes norvegicus, which were identified using a next-generation sequencing approach. In 40 dragonhead sap beetles from a population in southern Norway, we found 2-4 alleles per locus. Expected heterozygosity ranged from 0.18-0.65. Three of the loci showed significant deviation from Hardy-Weinberg equilibrium. After correcting for multiple tests, one pairwise locus combination displayed significant linkage disequilibrium. These novel microsatellite loci will be useful for future population structure, genetic diversity and conservation genetic studies of the dragonhead sap beetle., Oddmund Kleven, Anders Endrestøl., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15. Mating alters the rate of development of ovarioles in the ladybird, Propylea dissecta (Coleoptera: Coccinellidae)
- Creator:
- Shahid, Mhd, Siddiqui, Arshi, Omkar, and Mishra, Geetanjali
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, věk, beetles, Coccinellidae, age, Coleoptera, Propylea dissecta, mating status, ovariole development, egg maturation, egg load, 2, and 59
- Language:
- English
- Description:
- The influence of female mating status on ovarian development of the ladybird, Propylea dissecta (Mulsant) (Coleoptera: Coccinellidae), was investigated under laboratory conditions. We assessed the extent to which ovariole development was affected by mating and for that we initially created a base line by observing age specific ovariole development. Results show that the number of follicles in each ovariole increased with the age of both virgin and mated females up to the age of 3 days, thereafter, no increase in number of follicles was recorded. Ovariole width also increased with age in both virgin and mated females up to 4 days, thereafter, no increase in ovariole width was recorded. The ovariole width of mated females was significantly greater than that of virgin females. Egg maturation and the egg load started to increase at the age of 8 days in virgin females. Thereafter, it increased with increase in female age. While in mated females, immature eggs were recorded in their ovarioles from the age of 1 to 2 days. In mated females, however, the increase in the number of mature eggs per ovariole and egg load started when they were 3 days old. Egg load continuously increased with increasing female age., Mhd Shahid, Arshi Siddiqui, Omkar, Geetanjali Mishra., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
16. Metagenomic survey of bacteria associated with the invasive ladybird Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Dudek, Krzysztof, Humińska, Kinga, Wojciechowicz, Jacek, and Piotr Tryjanowski
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, slunéčko východní, beetles, Coccinellidae, Harmonia axyridis, Coleoptera, microbiota, bacteria community, 16s RNA, insect symbionts, 2, and 59
- Language:
- English
- Description:
- The Asian ladybird Harmonia axyridis is an invasive insect in Europe and the Americas and is a great threat to the environment in invaded areas. The situation is exacerbated by the fact that non native species are resistant to many groups of parasites that attack native insects. However, very little is known about the complex microbial community associated with this insect. This study based on sequencing 16S rRNA genes in extracted metagenomic DNA is the first research on the bacterial flora associated with H. axyridis. Lady beetles were collected during hibernation from wind turbines in Poland. A mean ± SD of 114 ± 35 species of bacteria were identified. The dominant phyla of bacteria recorded associated with H. axyridis were Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. Representatives of these phyla are common in the environment, e.g. in the soil, and are often identified as the dominant bacteria associated with arthropods. We also identified animal pathogenic bacteria, such as Burkholderia, Rhodococcus, Chlamydiae and Anaplasmataceae spp. (Neorickettsia helminthoeca and Ehrlichia ovina). We also identified Wolbachia pipientis in a single beetle. This bacterium is a causative agent of reproductive alterations in arthropods. These results support the enemy release hypothesis in the case of this ladybird invasion. Pathogenic bacteria were recorded in only a few samples. Moreover, male-killing bacteria such as Spiroplasma spp., Wolbachia spp. and Rickettsia spp. were only recorded in single insects so they cannot be responsible for the observed alterations in the sex-ratio of the ladybird population studied., Krzysztof Dudek, Kinga Humińska, Jacek Wojciechowicz, Piotr Tryjanowski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
17. Niche partitioning in tenebrionid species (Coleoptera: Tenebrionidae) inhabiting Mediterranean coastal dunes
- Creator:
- Fattorini, Simone, Bergamaschi, Davide, Mantoni, Cristina, Acosta, Alicia T. R., and Di Giulio, Andrea
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, potemníkovití, duny, beetles, Tenebrionidae, dunes, Coleoptera, geometric series, Mediterranean, niche overlap, niche preemption, 2, and 59
- Language:
- English
- Description:
- We analyzed the abundance, distribution and niche overlap of species (Pianka's Ojk index) in tenebrionid beetle communities inhabiting different biotopes in Tyrrhenian and Adriatic sand dunes. The rank abundance distribution of the different species has the form of a geometric series in both communities as predicted by the niche preemption hypothesis for communities in harsh environments. Mean niche overlap values did not deviate significantly from null expectations, which indicates random interspecific interactions. These results, coupled with evidence of species habitat preferences, led us to conclude that the community organization of tenebrionid species inhabiting coastal dunes is determined more by habitat preferences than interspecific competition., Simone Fattorini, Davide Bergamaschi, Cristina Mantoni, Alicia T. R. Acosta, Andrea Di Giulio., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
18. Population dynamics, seasonality and aphid prey of Cheilomenes sexmaculata (Coleoptera: Coccinellidae) in an urban park in central Japan
- Creator:
- Kawakami, Yasuko, Yamazaki, Kazuo, and Ohashi, Kazunori
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, mšice, beetles, Coccinellidae, aphids, Coleoptera, Cheilomenes sexmaculata, climate conditions, ladybird beetle, life cycle, urban vegetation, 2, and 59
- Language:
- English
- Description:
- The ladybird beetle, Cheilomenes sexmaculata (Fabricius), has been extending its distribution in and around urban areas at higher latitudes in Japan over the past 100 years. Between 2003 and 2011, we investigated the seasonal occurrence, aphid prey and population dynamics of this species in an urban park in Osaka City, central Japan. We found that C. sexmaculata completes three generations a year in Osaka. Overwintered adults emerge in March or April and produce two (or rarely one) generations by summer. Second-generation adults aestivate and subsequently produce another generation in autumn. This species feeds on five species of aphids that infest planted shrubs and alien weeds throughout the vegetative season. We analyzed the association between accumulated temperature and when overwintered adults first emerged. In addition, we determined the association between their time of emergence, peak abundance and last occurrence, and meteorological conditions. There was no association between the sum of effective temperatures and termination of adult overwintering. There was, however, an association between first occurrence and peak abundance, and climatic conditions, such as warm temperatures or low humidity. This species maintained a stable population in an urban park by becoming quiescent when climatic conditions were unfavourable or prey was scarce. We discussed these findings in relation to urban environmental factors, such as climate, food conditions and vegetation., Yasuko Kawakami, Kazuo Yamazaki, Kazunori Ohashi., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
19. Preliminary evidence of the horizontal transmission of Wolbachia between Crioceris leaf beetles (Coleoptera: Chrysomelidae) and their Asparagus host plants
- Creator:
- Kolasa, Michał, Montagna, Matteo, Mereghetti, Valeria, Daniel Kubisz, Mazur, Miłosz A., and Kajtoch, Łukasz
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, mandelinkovití, chřest, molekulární ekologie, beetles, Chrysomelidae, asparagus, molecular ecology, Alpha-Proteobacteria, Wolbachia, Crioceris, Coleoptera, horizontal transmission, Multilocus Sequence Typing, 2, and 59
- Language:
- English
- Description:
- Intracellular bacteria of the genus Wolbachia (α-Proteobacteria) are the most widespread endosymbionts of insects. Host infection is usually associated with alterations in reproduction, such as cytoplasmic incompatibility, the induction of parthenogenesis and offspring sex ratio bias: all phenomena that may influence host speciation. In the present study, by using well-established molecular tools, we investigated the presence of Wolbachia in leaf beetles of the genus Crioceris and their host plants, which are various species of Asparagus. Multilocus sequence typing of bacterial genes showed that despite their occurrence in the same habitat and feeding on the same plant, two species of Crioceris, C. quinquepunctata and C. quatuordecimpunctata, are infected by two different strains of Wolbachia. C. asparagi, C. paracenthesis and C. duodecimpunctata, which are sympatric with the infected species, do not harbour the bacterium. Interestingly, DNA of Wolbachia was detected in host plant tissues that are exploited by the beetles, providing evidence for the horizontal transmission of the bacterium between beetles and their host plants. Moreover, Wolbachia was detected in species of Crioceris that are not closely related., Michał Kolasa, Matteo Montagna, Valeria Mereghetti, Daniel Kubisz, Miłosz A. Mazur, Łukasz Kajtoch., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
20. Reproductive status of Tribolium castaneum (Coleoptera: Tenebrionidae) affects its response to infection by Steinernema feltiae (Rhabditida: Steinernematidae)
- Creator:
- Kramarz, Paulina, Małek, Dariusz, Gaweł, Maria, Drobniak, Szymon M., and Homa, Joanna
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, potemníkovití, sexuální dimorfismus, infekce, beetles, Tenebrionidae, sexual dimorphism, infections, Coleoptera, Tribolium castaneum, Rhabditida, Steinernematidae, Steinernema feltiae, phenoloxidase, 2, and 59
- Language:
- English
- Description:
- Gender-specific reproductive roles are important factors determining sexual dimorphism. Here, we investigate the effects of sex-based differences and reproductive status on the defence of Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae) against infection by Steinernema feltiae (Filipjev, 1934) (Rhabditida: Steinernematidae). Female and male beetles, either virgin or post-copulation, were exposed individually to nematodes. Individuals were then sampled every 12 h, dissected, and checked for the presence of nematodes; we also measured their phenoloxidase (PO) activity. Reproductive status affected resistance to nematodes and PO activity as infected virgin individuals had a higher PO activity and lower mortality than reproducing individuals, with no differences between sexes. Mortality also increased with time, while PO activity did not change. Parasite load was related to reproductive status and sex, with reproducing females with the highest parasite loads in all treatments, and virgin males with more nematodes than sexually active males. Our results indicate that the costs of reproduction impair the immunological system of T. castaneum similarly in both sexes. It is possible, however, that other components of the immunological system that we did not measure, such as lysozyme activity, are impaired by infection with S. feltiae in a sex-specific way., Paulina Kramarz, Dariusz Małek, Maria Gaweł, Szymon M. Drobniak, Joanna Homa., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
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