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
Paysandisia archon (Burmeister, 1980) (Lepidoptera: Castniidae) is an accidentally introduced pest that damages palm trees in the northern Mediterranean area. To our knowledge, there are no experimental studies on its mating behaviour, and little is known about its biology and ecology. In the present study, we used outdoor experiments to investigate several characteristics of the reproductive behaviour of P. archon: sexual maturity, diel periodicity of mating, occurrence of polyandry and delay between mating and laying eggs. The results indicate that 73% of the individuals studied were sexually mature three hours after adult emergence. Mating peaked between 14:00 h and 15:00 h and 87% of the females were fertilized and started laying eggs 1.25 (± 1.14) days after mating. Females were generally monandrous, but nevertheless remained attractive after mating. The results of this study provide the necessary background knowledge for studying several aspects of P. archon reproductive biology, in particular oviposition, sex pheromones and their role in mediating mating behaviour in this pest. These results are the first step in developing tools for monitoring populations of this pest., Roxane Delle-Vedove ... [et al.]., and Obsahuje seznam literatury
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
1_The respiratory metabolism of different polyphenic forms of the pea aphid, including wingless and winged asexual females (virginoparae), sexual females (oviparae) and winged or wingless adult males, was investigated using a micro-respirographic method. The records revealed sub-nanoliter amounts per min of O2 consumption or CO2 output. Respiratory metabolism of individuals was monitored for 3 to7 h after removal of the aphid from the food plant. Most of the recordings were for relatively large (3.5 mg), wingless asexual females (virginoparae). These aphids exhibited a continuous and very regular respiratory gas exchange (example: specimen of 3.5 mg body mass consumed 180 nl of O2 per min; released simultaneously 300 nl CO2 per min; = standard metabolic rate of 3085 µl O2 / g / h; R.Q. = 1.66). This continuous pattern of respiration occurred only when the aphids were kept at relatively high humidity. By contrast, aphids of various seasonal forms exhibited discontinuous respiratory gas exchange when kept in relatively dry air (atmospheric, room conditions). These patterns can be briefly described as follows: (a) Short and rather small micro-cycles of CO2 emission, manifested usually by the sudden expiration of 60–120 nl of CO2 once every 5 min; (b) Larger bursts of 240–480 nl of CO2 with a periodicity of one hour; (c) Enormously large, discontinuous bursts of 10–14 µl CO2, duration 10–30 min, repeated with a periodicity of several hours. There was no constant pattern of diffusive CO2 emission (DGC). The aphids exhibited a pattern of CO2 release that was appropriate for the external conditions, such as temperature and humidity, and internal physiological conditions such as metabolic activity, availability of reserve substances (carbohydrate, lipid) and water. Certain stages (wingless virginoparae) exhaled volumes of CO2 greatly in excess of their O2 consumption (R.Q. over 1.5)., 2_Sudden exhalations of CO2 from the body were a consequence of a bulk production and outflow of CO2 and not due to the diffusion of CO2 previously accumulated within the tracheal system. Due to their generally high metabolic activity (1142 to 6780 µl O2 / g / h), aphid tissue and organs produced relatively large amounts of metabolically formed carbonic acid. The resulting respiratory acidaemia was moderated by outbursts of gaseous CO2, liberated from liquid carbonate buffers by a regulatory mechanism based on enzymatic hydration and neutralization of carbonic acid by discontinuous formation of gaseous CO2., Karel Sláma, Pavel Jedlička., and Obsahuje seznam literatury
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
The effects of tannic acid on mean values and genetic variation in fitness-related traits (mass, relative growth rate) and specific activities of digestive enzymes (total proteases, a-glucosidase and lipase), and genetic variation in their plasticity, were investigated in fifth instar larvae of Lymantria dispar L. (Lepidoptera: Lymantriidae) originating from two populations with different host use histories (oak and locust-tree). The two populations did not differentiate with respect to fitness-related traits, i.e. adverse effects of tannic acid were similar in both populations. However, Robinia larvae, which originated from the locust-tree forest, were characterized by higher total protease and lipase activity and lower a-glucosidase activity than Quercus larvae, which originated from the oak forest. Higher plasticity of lipase and lower plasticity of a-glucosidase in response to tannic acid were also recorded. Quantitative genetic analysis revealed mostly significant expression of genetic variation in the examined traits and trait plasticity, suggesting the potential for evolution of adaptive plastic responses to new environmental conditions and presence of a stressor. The genetic correlations observed between the environments significantly differed from “one”, which indicates there are no constraints on the evolution of trait plasticity., Marija Mrdakovic ... [et al.]., and Obsahuje seznam literatury
Various disturbances in forests often result in the formation of open habitats with characteristics that are distinctly different from those of the original forest (microclimate, illumination, stand age and composition). These disturbances affect the habitat heterogeneity in time and space and seem to drive forest succession and changes in biodiversity in forests. Little is known about how the colonization of deforested habitats by Orthoptera is influenced by environmental factors. We studied the association between the structure of orthopteran assemblages and the age of clear-cuts, vegetation structure and other environmental parameters (size, elevation, altitude). This involved 33 clear-cuts of three age categories in broadleaved forests dominated by European beech. The Orthoptera were sampled using sweep netting and by counting individuals recorded along transects that ran parallel to those used for recording the structure of the vegetation. We recorded significant differences in the number and abundance of species in the three age categories of clear-cuts. Grasshopper species were more abundant than bush-crickets in first year clear-cuts. Species capable of flight occured in all three age categories of clear-cuts (>62% of the 27 species recorded). All the species of Orthoptera identified were present in two year-old clear-cuts. The species composition and abundance of Ensifera and Caelifera differed in their association with the six vegetation parameters studied. While the Caelifera occurred in habitats with bare ground the Ensifera mainly occurred in those with a higher proportion of shrubs and trees. There was also a positive correlation between number of species of Orthoptera and area of the clear-cut regardless of its age as well between the number of species of Orthoptera and elevation., Anna Sliacka, Anton Krištín, Ladislav Naďo., and Obsahuje seznam literatury
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
The planthopper genus Pseudoparicana Melichar, 1914 is revised. Three previously known species, P. curvifera (Distant, 1907), P. sanguinifrons Muir, 1931 and P. tepida Melichar, 1914 are re-described and P. analoga Wang & Malenovský sp. n. is described as new. Lectotypes are designated for P. curvifera and P. tepida. An identification key and illustrations of diagnostic characters, including male and female genitalia, are provided for all taxa and the systematic position of this genus and the asymmetry of the genitalia of the species are briefly discussed. As far as known, the distribution of Pseudoparicana is restricted to New Guinea and the Aru Islands., Rong-Rong Wang ... [et al.]., and Obsahuje seznam literatury
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