Lygus lineolaris (Palisot de Beauvois, 1818) (tarnished plant bug) is a serious pest of cotton (Gossypium hirsutum L.) in the Delta region as compared to cotton in the Hills region of the state of Mississippi in USA. The reason for this is unclear but it was hypothesized that the plant cell wall degrading polygalacturonase enzyme system in the salivary glands of L. lineolaris from the Delta could be better adapted for cotton, which is grown more predominantly in the Delta region than in the Hills region. Expression analysis of three primary polygalacturonase genes (LlPG1, LlPG2 and LlPG3) was conducted in laboratory reared and field collected populations of L. lineolaris. Assay of polygalacturonase enzyme activity was also conducted to compare wild collected populations. Initial laboratory and field data revealed gene expression differences in sex, age, region, and host plant which guided the direction of our subsequent study during 2013 and 2014. Based on the results of this study, we propose that the three genes studied may not be reflective of the entire polygalacturonase enzyme system and may not be solely responsible for the observed adaptation of L. lineolaris to cotton in the Delta region than in the Hills region. Analyses also revealed that the expression of the three targeted polygalacturonase genes was affected by the host plant from which the insects were collected and that adults had higher polygalacturonase expression than nymphs. Taken together, our results provide strong evidence for developmental stage specific and host plant based change in expression of PG genes in the salivary glands of L. lineolaris. This, however, was not reflected in total polygalacturonase enzyme activity which was not significantly different between regions, hosts, sex, or developmental stage., Daniel Fleming, Natraj Krishnan, Fred Musser., and Obsahuje bibliografii
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
Macrolophus pygmaeus (Hemiptera: Miridae) is an important predator of pests of horticultural crops and here its ability as a predator of Acyrthosiphon pisum (Hemiptera: Aphididae) is addressed for the first time. The percentage predation of the different aphid instars and the number partially consumed were studied. Our results, obtained using choice and no-choice tests, revealed that M. pygmaeus caught and consumed more young than later instars of A. pisum, which confirms results of previous studies using other species of aphids. We also studied the interactions between predators (male/female) foraging in the same patch. When the prey/predator ratio is kept constant at 10 : 1 the average percentage of aphids completely consumed by individual females or males does not change with increase in the number of foraging predators. However, the number of partially consumed aphids decreased when females shared the same patch. In contrast, there was an increase in the number of aphids partially consumed when two males shared the same patch. The results were discussed in terms of potential predator foraging strategies since intraspecific competition is a key factor modulating the dynamics of prey-predator systems., Juliana Durán Prieto, Vincenzo Trotta, Paolo Fanti, Cristina Castañé, Donatella Battaglia., and Obsahuje bibliografii
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
The oldest butterfly fossil known, which was formed about 55 Ma in what is now Denmark, is described. The fragments of its forewing venation indicates it belongs to the Hesperiidae. Further reconstruction indicates that it fits in the Coeliadinae and is close to the extant genera Hasora and Burara. It is here described as Protocoeliades kristenseni gen. et sp. n. It is the first butterfly fossil found on a continent (Europe) where its closest relatives do not currently occur. Its position on the phylogenetic tree of the Coeliadinae and its importance in understanding the time dimension in the evolution of butterflies, and their ecological and biogeographic implications are discussed., Rienk De Jong., and Obsahuje bibliografii
Several studies address the question of which forest attributes are most important for the conservation of biodiversity. Unfortunately, there are no unequivocal answers because the response of a biological group to changes in forest structure depends on its natural history and scale of organization. It is important to increase our knowledge of the potential relationships between under studied groups of species and forest variables in order to adopt timber harvesting strategies not detrimental to biodiversity, especially in old-growth forests. We assessed the importance of 10 forest attributes and old-growth for Psychidae (Lepidoptera) species and communities. Research was carried out in 12 forest stands in a mountainous beech dominated landscape in southern Italy, in the middle of the Mediterranean Basin. Samples were collected in 2001 and 2013 and data were merged after pairwise comparison analyses that confirmed the long term stability of communities. Correspondence Analysis, Cluster Analysis and non-parametric Spearman Rank Order Correlation were used to identify determinants of Psychidae abundance and diversity. We collected 2,732 Psychidae belonging to 8 species. Correspondence analysis identified old-growth as the main determinant of communities. Most significant attributes for individual species were beech dominance, diameter at breast height and its standard deviation. For Taleporia defoliella there were positive correlations with these forest parameters, whereas for Psyche crassiorella the correlations were negative. This study underlined the importance of forest attributes associated with old-growth forests for sustaining biodiversity. These findings indicate the need to incorporate these attributes in forest planning, especially those aspects that are easily recognizable such as the number of large trees., Stefano Scalercio, Teresa Bonacci, Rosario Turco, Vincenzo Bernardini., and Obsahuje bibliografii
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
We studied the effects of the overstory canopy cover on ground-dwelling harvestmen communities in European beech forests in the Western Carpathian Mts. We analyzed the differences in species richness, abundance and composition in two tree canopy cover categories (closed and open canopy). Overall, 1765 individuals belonging to 16 species were caught using pitfall traps. Repeated-measures ANOVA revealed that under both closed and open canopies a similar absolute and rarefied species richness and number of individuals (standardized to 100 pitfall trap days) were caught, and that both species richness and abundance were affected by the season (i.e., time of trap replacement); yet the total number of individuals trapped was more than two times greater under the open canopy than under the closed canopy. Despite the subtle differences in the taxonomic composition of the catches under the open and closed canopies revealed by DCA followed by RDA, the composition of ground-dwelling harvestmen assemblages differed under the two canopy covers. The open canopy was more suitable for heliophilic, xerothermic eurytopic harvestmen species typical for open and ecotonal habitats, such as Egaenus convexus (C.L. Koch) and Oligolophus tridens (C.L. Koch) but still suitable for hemihygrophilic Lophopilio palpinalis (Herbst). The closed canopy stands were preferred by shade-tolerant, hygrophilic eurytopic harvestmen species, such as Trogulus sp. Latreille, Dicranolasma scabrum (Herbst) and Platybunus bucephalus (C.L. Koch). Our results highlight the importance of intra-habitat heterogeneity of a harvestmen community., Ľudmila Černecká, Ivan Mihál, Benjamín Jarčuška., and Obsahuje bibliografii
In Indian agro-ecosystems Rhynocoris marginatus (F.) is one of the most abundant predatory arthropods and feeds on a wide range of insect pests. We investigated the responses of R. marginatus to six species of cotton pests: Spodoptera litura (F.), Sylepta derogata (F.), Pericallia ricini (F.), Mylabris indica (Thunberg), Mylabris pustulata (Thunberg) and Dysdercus cingulatus (F.), in terms of its predatory behaviour (approach and handling times), weight gain, macromolecular profile (content of carbohydrates, proteins, free aminoacids and lipids) and haemocytic profile. We also determined the predator's reliance on kairomones from different species of prey. Larvae of the species of Lepidoptera studied were approached and captured more quickly than adults of the two meloid coleopteran and one heteropteran pest and were more beneficial to the predator in terms of weight gain. Predators had a higher total protein content when reared on larvae of the three lepidopteran species, higher lipid content when reared on adults of the two meloid coleopteran species and a higher carbohydrate content when reared on adults of one heteropteran species. The number of haemocytes was greater in predators reared on larvae of the Lepidoptera studied, followed by those reared on adults of the heteropteran and lowest in those reared on adults of the two meloid coleopterans. Response to kairomones was strongest for S. litura followed by S. derogata and M. pustulata. We conclude that the Lepidoptera studied tended to be, for this predator, superior prey, with S. litura being especially beneficial and the prey species for which R. marginatus has the highest kairomonal preference. Moreover, we propose that R. marginatus may be useful as a biocontrol agent against lepidopteran cotton pests., Kitherian Sahayaraj, Subramanian Muthu Kumar, Annie Enkegaard., and Obsahuje bibliografii
In this paper the strictly attaphilous Central- and South American genus Phoxonotus Marseul, 1862 is revised. Based on the structure of their antennal cavities, the species of Phoxonotus are newly split into two subgenera: Phoxonotus Marseul, 1862 and Alienosternus subgen. n. (type species Saprinus venustus Erichson, 1834). The subgenus Phoxonotus contains three species: Phoxonotus (P.) tuberculatus Marseul, 1862 (French Guyana, Suriname, Brazil: Pará, Mato Grosso), P. (P.) lectus Lewis, 1902 (eastern Peru) and the newly described P. parvotuberculatus sp. n. (Guatemala, Costa Rica). The subgenus Alienosternus subgen. n. contains two species: Phoxonotus (Alienosternus) venustus (Erichson, 1834) (Brazil: Bahia) and P. (Alienosternus) fryi Lewis, 1879 (Brazil: Rio de Janeiro and Bahia). P. tuberculatus Marseul, 1862 is synonymized with P. suturalis Lewis, 1907, syn. n. Lectotype of Phoxonotus fryi Lewis, 1879 is designated. Genitalia of the males for the species for which they are available are illustrated, most type specimens are imaged and scanning electron micrographs of P. tuberculatus provided. Mouthparts and sensory structures of the antennal club of P. tuberculatus are depicted., Tomáš Lackner., and Obsahuje bibliografii