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Results 331 to 360 of 1442:

The year-round phenology of the migratory Red Admiral Vanessa atalanta (Lepidoptera: Nymphalidae) in a Mediterranean area in southern SpainOriginal article

Mariano CUADRADO

Eur. J. Entomol. 114: 517-525, 2017 | DOI: 10.14411/eje.2017.066

Many studies report the migratory status of Vanessa atalanta in the Palearctic. Available evidence indicates that this species migrates north in spring to reproduce and south in autumn to reproduce in the Mediterranean area. However, little is known about the year-round phenology and their overwintering in southern regions. Here, I present data on the year-round phenology of adult V. atalanta recorded during a three year period (2014-2016) at 5 lowland sites (< 80 m a.s.l.) near the coast close to Cádiz (southern Spain). Overall, a total of 826 imagoes were recorded along 1499.3 km of Butterfly Monitoring Scheme (BMS) transects. Abundance was 0.55 butterflies/km (data for all sites and years pooled) and varied greatly among sites and years. Coinciding with the migratory status, imagoes were recorded from September to June each year and the year-round abundance showed a typical bimodal distribution with two peaks of abundance, one in late winter (February) and another in autumn (November). Abundance was higher in spring (0.87 butterflies/km) than in autumn (0.60 butterflies/km). The emergence of a local generation in late winter was also recorded. My results agree with the migratory phenology of this species in the Palearctic and support the year round phenology data reported by Stefanescu (2001).

New fossil genus and species of Sinoalidae (Hemiptera: Cercopoidea) from the Middle to Upper Jurassic deposits in northeastern ChinaOriginal article

Yan-Zhe FU, Di-Ying HUANG

Eur. J. Entomol. 115: 127-133, 2018 | DOI: 10.14411/eje.2018.011

A new fossil genus and species of Sinoalidae, Stictocercopis wuhuaensis gen. et sp. n., from the Middle to Upper Jurassic Haifanggou Formation at Daohugou, Inner Mongolia, northeastern China is described, illustrated and its systematic position discussed, on the basis of four complete well-preserved specimens. The new genus distinctly differs from other sinoalids in having relatively complex wing venation and tegmen spots. The intra-specific variation in venation is also discussed. The new discovery increases the palaeodiversity of sinoalids in the early assemblage of the Yanliao biota from the Daohugou beds.

Does Hartigiola annulipes (Diptera: Cecidomyiidae) distribute its galls randomly?Original article

Sebastian PILICHOWSKI, Marian J. GIERTYCH

Eur. J. Entomol. 115: 504-511, 2018 | DOI: 10.14411/eje.2018.050

It is expected that environmental conditions impact the distribution of galls on host plants. Moreover, insects may induce their galls randomly or choose certain parts of a host to induce such growths. This study aimed to determine whether or not the gall midge, Hartigiola annulipes (Diptera: Cecidomyiidae), which induces galls on leaves of the European beech (Fagus sylvatica), prefers leaves facing a particular cardinal direction. In addition, we wanted to ascertain whether the galls are evenly spread across three leaf zones: proximal, median and distal, distinguished by dividing leaf area along the midrib. The results show that H. annulipes chose leaves facing various directions in different studied locations, and leaf choice is not restricted to the specific leaf area, a parameter that accurately reflects the light conditions of leaf growth. Moreover, the medial leaf zone was preferred, while the distal zone was avoided. The choice of the leaf zone modified the distance between the mid-rib and a gall. Gall distribution in the crown of trees is probably random, while at the leaf level, it is determined by leaf morphology.

Metagenomic survey of bacteria associated with the invasive ladybird Harmonia axyridis (Coleoptera: Coccinellidae)Original article

Krzysztof DUDEK, Kinga HUMIŃSKA, Jacek WOJCIECHOWICZ, Piotr TRYJANOWSKI

Eur. J. Entomol. 114: 312-316, 2017 | DOI: 10.14411/eje.2017.038

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.

Daily survival and dispersal of adult Rhagonycha fulva (Coleoptera: Cantharidae) in a wooded agricultural landscapeOriginal article

Laura E. RODWELL, Jennifer J. DAY, Christopher W. FOSTER, Graham J. HOLLOWAY

Eur. J. Entomol. 115: 432-436, 2018 | DOI: 10.14411/eje.2018.043

Studies of insect population under field conditions to establish survival rates, longevity and dispersal rates are rare in the literature. These types of studies are important and can be used to inform studies of the effects of landscape composition and configuration on levels of biodiversity. Here the Cantharidae beetle, Rhagonycha fulva is studied under field conditions to derive estimates of daily survival rates for both males and females as well as local dispersal rates. Survival was studied at two sites, one in Wales and another in England, whilst dispersal was examined only at the Welsh site. Beetles were marked using different coloured enamel paints at the mid-point of a 200 m linear transect. The beetles were almost exclusively found (and marked) on common hogweed, Heracleum sphondylium. No difference in survival was found between males and females at both of the sites. The survival rates found at the two sites also did not differ. The overall daily survival rate was 0.771 equating with a median longevity of 4.37 days. Casual observations yielded a small number of marked individuals in excess of 400 m away from the point of marking. Movement of males along the transect differed from females. Marked females were never found far from the point of marking whilst males moved further away with time. This difference in behaviour is discussed in terms of hypothesized insect dispersal behaviour following emergence as mobile adults.

First fossil tooth-necked fungus beetle (Coleoptera: Derodontidae): Juropeltastica sinica gen. n. sp. n. from the Middle Jurassic of China

Chenyang CAI, John F. LAWRENCE, Adam ¦LIPIŃSKI, Diying HUANG

Eur. J. Entomol. 111 (2): 299-302, 2014 | DOI: 10.14411/eje.2014.034

The first fossil tooth-necked fungus beetle, Juropeltastica sinica gen. n. sp. n., is described and illustrated based on a single impression fossil from the Middle Jurassic Daohugou beds (ca. 165 Ma) of northeastern China. It represents the first definitive fossil belonging to the extant family Derodontidae. Juropeltastica is placed in Derodontidae based on its overall body shape and size, head with complex systems of tubercles and grooves, pronotum with dentate lateral carinae, open mesocoxal cavities bordered by mesepimeron and metanepisternum, excavate metacoxae, and 5-segmented abdomen. The occurrence of a reliable derodontid fossil from 165 million years ago places Derodontidae among the small but growing number of beetle families of known Middle Jurassic age, which is important in the dating of phylogenetic trees.

First cytogenetic study of Coleorrhyncha: Meiotic complement of Xenophyes cascus (Hemiptera: Peloridiidae)

Snejana GROZEVA, Valentina KUZNETSOVA, Viktor HARTUNG

Eur. J. Entomol. 111 (2): 303-306, 2014 | DOI: 10.14411/eje.2014.023

Cytogenetic information on the hemipteran suborder Coleorrhyncha is here provided for the first time. The New Zealand peloridiid species, Xenophyes cascus Bergroth, 1924 (Hemiptera: Coleorrhyncha: Peloridiidae), was found to display testes with a single follicle each, holokinetic chromosomes (like other Hemiptera), a karyotype of 2n = 26 + X(0) and a single chiasma per bivalent in male meiosis. Comparative analysis of sex chromosome systems in all four hemipteran suborders (Sternorrhyncha, Auchenorrhyncha, Heteroptera and Coleorrhyncha) allowed inference that an X(0) sex determining system was ancestral within the Hemiptera, whilst the XY-system was most likely a derived condition within the Heteroptera.

Pollen resources used by Chrysoperla agilis (Neuroptera: Chrysopidae) in the Azores, Portugal

Leila NUNES MORGADO, Roberto RESENDES, Mónica MOURA, Maria A. MATEUS VENTURA

Eur. J. Entomol. 111 (1): 143-146, 2014 | DOI: 10.14411/eje.2014.015

There are approximately 1200 described species of Chrysopidae, many of which are predators of agricultural pests. Species of Chrysoperla are mass-produced and sold for use as biological control agents of agricultural pests in Europe, Asia, North and South America. Chrysoperla agilis, a member of the "carnea group" of Chrysoperla, has the potential to be biocontrol agent and is native to the Azores, and therefore a local candidate for use in IPM of pests, such as aphids and scale insects. Given that many adult Chrysopidae feed on pollen and honeydew and the biology of Ch. agilis is not well understood, we studied the preferences of Ch. agilis adults living in a greenhouse on the campus of the University of the Azores for feeding on different types of pollen. Twenty-six species of flowering plants, belonging to 16 families and 24 genera, all previously recorded on Sao Miguel Island, were found in the greenhouse. Pollen grains from each species were collected and incorporated in a reference catalogue. Additionally, 40 adults of Ch. agilis were collected (20 in December 2012 and 20 in January 2013) and the pollen in guts identified. Of the 26 species of plants in the greenhouse 14 were used as sources of pollen by the lacewings. Pollen of Plantago lanceolata L. was the most frequently recorded pollen in the gut contents. The adults of this chrysopid fed mainly on the pollen of species of plants belonging to the Asteraceae, Plantaginaceae and Poaceae. The species richness (S = 12), diversity index (H' = 2.123) and equitability (J' = 0.8543) of the January sample are greater than those of the December sample. Similarity of the samples collected in the 2 months was 0.75. From these results we infer that it is important to maintain or increase plant biodiversity in agroecosystems as weeds provide trophic resources for insects that are beneficial to agriculture.

Fungi associated with Ips acuminatus (Coleoptera: Curculionidae) in Ukraine with a special emphasis on pathogenicity of ophiostomatoid speciesOriginal article

Kateryna DAVYDENKO, Rimvydas VASAITIS, Audrius MENKIS

Eur. J. Entomol. 114: 77-85, 2017 | DOI: 10.14411/eje.2017.011

Conifer bark beetles are well known to be associated with fungal complexes, which consist of pathogenic ophiostomatoid fungi as well as obligate saprotroph species. However, there is little information on fungi associated with Ips acuminatus in central and eastern Europe. The aim of the study was to investigate the composition of the fungal communities associated with the pine engraver beetle, I. acuminatus, in the forest-steppe zone in Ukraine and to evaluate the pathogenicity of six associated ophiostomatoid species by inoculating three-year-old Scots pine seedlings with these fungi. In total, 384 adult beetles were collected from under the bark of declining and dead Scots pine trees at two different sites. Fungal culturing from 192 beetles resulted in 447 cultures and direct sequencing of ITS rRNA from 192 beetles in 496 high-quality sequences. Identification of the above revealed that the overall fungal community was composed of 60 species. Among these, the most common were Entomocorticium sp. (24.5%), Diplodia pinea (24.0%), Ophiostoma ips (16.7%), Sydowia polyspora (15.1%), Graphilbum cf rectangulosporium (15.1%), Ophiostoma minus (13.8%) and Cladosporium pini-ponderosae (13.0%). Pathogenicity tests were done using six species of ophiostomatoid fungi, which were inoculated into Scots pine seedlings. All ophiostomatoid fungi tested successfully infected seedlings of Scots pine with varying degrees of virulence. Ophiostoma minus was the only fungus that caused dieback in inoculated seedlings. It is concluded that I. acuminatus vectors a species-rich fungal community including pathogens such as D. pinea and O. minus. The fungal community reported in the present study is different from that reported in other regions of Europe. Pathogenicity tests showed that O. minus was the most virulent causing dieback in seedlings of Scots pine, while other fungi tested appeared to be only slightly pathogenic or completely non-pathogenic.

Effect of nutritious and toxic prey on food preference of a predaceous ladybird, Coccinella septempunctata (Coleoptera: Coccinellidae)Original article

Mushtaq A. GUROO, Ahmad PERVEZ, Kuldeep SRIVASTAVA, Rakesh K. GUPTA

Eur. J. Entomol. 114: 400-406, 2017 | DOI: 10.14411/eje.2017.051

We investigated the predatory potential and food preference of different life stages of Coccinella septempunctata L. for a nutritious aphid (mustard aphid, Lipaphis erysimi) and toxic aphid (cabbage aphid, Brevicoryne brassicae). We provided all the life stages of C. septempunctata with either L. erysimi or B. brassicae and found that the second, third and fourth instar larvae and adult females of this predator consumed daily greater numbers of L. erysimi. However, the first instar larvae and adult males consumed similar numbers of both of these aphids. In choice condition, each larva, adult males and females were each provided separately with a mixed aphid diet in three proportions (i.e. low: high, equal: equal and high: low densities of L. erysimi: B. brassicae). We hypothesized that life stages of C. septempunctata will prefer L. erysimi regardless of its proportions. Laboratory experiments supported this hypothesis only at the adult level in terms of high values of β and C preference indices. However, it rejects this hypothesis at the larval level, as larvae preferred B. brassicae when provided with certain combinations and showed no preference in a few combinations. We infer that mixtures of nutritious and toxic aphids may enable this ladybird to overcome any probable nutritional deficiency and/or reduce the toxicity of a toxic diet, especially for the larvae. Results of the treatment in which a high proportion of B. brassicae were consumed along with fewer L. erysimi indicates that a mixed diet could be better for the development of immature stages of C. septempunctata.

A comparative study of the abdominal trichobothria of Trichophora, with emphasis on Lygaeoidea (Hemiptera: Heteroptera)Original article

Cuiqing GAO, Dávid RÉDEI, Xueqin SHI, Bo CAI, Ke LIANG, Shuo GAO, Wenjun BU

Eur. J. Entomol. 114: 587-602, 2017 | DOI: 10.14411/eje.2017.072

Members of the clade Trichophora (Hemiptera: Heteroptera: Pentatomomorpha) have trichobothria on their abdominal sterna. There is no comparative study of the fine structure of abdominal trichobothria in the group and until now the trichobothria of their immatures were virtually unknown. The fine structure of the abdominal trichobothrial complex (= the trichobothrium and its associated structures) of adults of 98 species belonging to 25 families in 5 superfamilies and larvae of 7 species belonging to 7 families in 2 superfamilies of Trichophora were examined using scanning electron microscopy. This study indicates that the fine structure of the abdominal trichobothria is very variable and useful for determining evolutionary lineages within the clade. Six types of bothria, three of trichomes and three of microtrichia are recognized and their evolutionary transformations discussed. Changes in the size of trichomes, and density and size of the microtrichia during the postembryonic development of selected species are discussed.

Immunomodulation in insects post-treatment with abiotic agents: A review

El-Sayed H. SHAURUB

Eur. J. Entomol. 109 (3): 303-316, 2012

The effects of different abiotic agents that may modulate the activity of an insect's immune system are reviewed. These agents include insecticides, chitin synthesis inhibitors, juvenile hormone analogues, inert particles, antibiotics, heavy metals, radiation and miscellaneous substances. The significance of studying immunomodulation in insects treated with abiotic agents in relation to both insect control and insect-borne parasitic diseases and the link between immunomodulation in insects post-treatment with both abiotic and biotic agents are discussed.

Relationships between Psychidae communities (Lepidoptera: Tineoidea) and the ecological characteristics of old-growth forests in a beech dominated landscapeOriginal article

Stefano SCALERCIO, Teresa BONACCI, Rosario TURCO, Vincenzo BERNARDINI

Eur. J. Entomol. 113: 113-121, 2016 | DOI: 10.14411/eje.2016.014

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.

Revision of the attaphilous genus Phoxonotus (Coleoptera: Histeridae: Saprininae)Original article

Tomáą LACKNER

Eur. J. Entomol. 113: 240-258, 2016 | DOI: 10.14411/eje.2016.029

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.

Effects of habitat and landscape features on grassland Orthoptera on floodplains in the lower reaches of the Tisza River BasinOriginal article

Attila TORMA, Miklós BOZSÓ

Eur. J. Entomol. 113: 60-69, 2016 | DOI: 10.14411/eje.2016.007

The Tisza River Basin is an important area as it is a green corridor in which there are highly endangered habitats and a high level of biodiversity. The patterns in the species richness of invertebrates and the environmental conditions affecting these patterns are poorly studied in the grassy habitats in the lower reaches of the Tisza River Basin. The present study focuses on the effects of flooding, habitat and landscape features on the species richness of orthopterans at 24 grassland sites in two different landscapes. The relations between the explanatory variables and the pattern of diversity of orthopterans with different life-history traits were studied, using ordination and Generalized Linear Mixed Models. Although the influential factors for the different trait groups differed, we suggest that landscape features are the most important in shaping orthopteran assemblages, whereas habitat characteristics and flooding have comparatively little effect. Habitat characteristics affected only the non-xerophilous and Ensifera species and only the species richness of non-xerophilous orthopterans in flooded and non-flooded sites differed. We emphasize that even in countries where there are still considerable areas of high value natural grasslands, such as Hungary, non-protected meadows, linear grassy habitats (dikes, ditch banks, road verges, etc.) need more attention and should be given higher priority in the conservation of invertebrates.

Assessing the efficiency of UV LEDs as light sources for sampling the diversity of macro-moths (Lepidoptera)Original article

Marco INFUSINO, Gunnar BREHM, Carlo DI MARCO, Stefano SCALERCIO

Eur. J. Entomol. 114: 25-33, 2017 | DOI: 10.14411/eje.2017.004

Light trapping is the most widely used tool for determining the diversity of nocturnal Lepidoptera, but UV LEDs have yet to be used as light sources for the large-scale monitoring of Lepidoptera. We assessed the efficiency of this novel light source for sampling moths using a Heath type moth equipped with a strip of 150 high brightness UV LEDs (emission peak 398 nm, ~ 15 W) powered by a 12 V battery. We compared the number of individuals, the number of species and the Geometridae / Noctuidae ratio recorded for the samples collected using UV LED traps with those collected in two monitoring programs carried out in the same geographic region using two different light sources: a 200 W incandescent lamp (Rothamsted trap) and a 160 W mercury vapour lamp (manual catch). The total catch consisted of 61,120 individuals belonging to 699 species. The species richness rarefaction curves revealed that the Rothamsted trap collected fewer species and individuals than UV LED traps. Furthermore, the median numbers of species and individuals caught by UV LED traps fell within the range of those caught by mercury vapour lamp traps. In addition, the community composition recorded using incandescent lamps and UV LEDs was similar. The data obtained using UV LED traps, in absolute terms and in comparison with the other light sources and different sampling methods, clearly reveal that this light source is suitable for sampling macro-moth communities. For field work UV LEDs have many advantages, as they are resistant to mechanical damage, easily protected from heavy rain and energy efficient.

New species of Cicadocoris (Hemiptera: Coleorrhyncha: Progonocimicidae) from mid-Jurassic deposits in northeastern ChinaOriginal article

Jia-Qian JIANG, Di-Ying HUANG

Eur. J. Entomol. 114: 355-364, 2017 | DOI: 10.14411/eje.2017.045

A new progonocimicid bug named Cicadocoris parvus sp. n. is described from the mid-Jurassic Haifanggou Formation at Daohugou, Ningcheng County, Inner Mongolia, northeastern China. It differs from other species by being distinctly smaller, veins dSc, R1 and Rs run parallel to one another and are nearly evenly spaced on left tegmen, widest length of apical half/basal half of left tegmen is 1.1 and that of right tegmen is 1.0. Thus, there are at least three species of Cicadocoris (Progonocimicidae) described from Daohugou. All these species are relatively abundant in the Haifanggou Formation and are remarkable representatives of the early Yanliao biota.

Variation of thorax flight temperature among twenty Australian butterflies (Lepidoptera: Papilionidae, Nymphalidae, Pieridae, Hesperiidae, Lycaenidae)Original article

Gabriel NÈVE, Casey HALL

Eur. J. Entomol. 113: 571-578, 2016 | DOI: 10.14411/eje.2016.077

Thermal requirements for flight in butterflies is determined by a combination of external factors, behaviour and physical constraints. Thorax temperature of 152 butterflies was monitored with an infra-red thermometer in controlled laboratory conditions. The temperature at take-off varied from 13.4°C, for a female Heteronympha merope to 46.3°C, for a female Junonia villida. Heteronympha merope, an understorey species, had the lowest recorded take-off temperatures, with females flying at a much lower thorax temperatures than males. Among the tested butterfly species, warming-up rate was positively correlated with take-off temperature and negatively with body mass. Wing loading is a major variable in determining the thorax flight temperature. Butterflies with the highest wing-loadings experienced the highest thorax temperatures at take-off. A notable exception to this rule is Trapezites symmomus, the only Hesperiidae of our data set, which had thorax flight temperatures of 31.5°C and 34.5°C, well within the range of the observed butterflies, despite a wing load ca. five times higher. The high thorax temperature recorded in J. villida is probably linked to its high flight speed. The results highlight the importance of physical constraints such as body size on the thermal requirements for flight across a range of butterfly species.

Field and laboratory studies on drought tolerance and water balance in adult Pergalumna nervosa (Acari: Oribatida: Galumnidae)Original article

Stine SLOTSBO, Jesper G. SØRENSEN, Josef STARY, Martin HOLMSTRUP

Eur. J. Entomol. 114: 86-91, 2017 | DOI: 10.14411/eje.2017.012

We studied the water balance, body fluid osmolality and survival of the oribatid mite, Pergalumna nervosa, when exposed to drought in field and laboratory experiments. In a replicated field experiment we artificially lowered the soil water content by putting roofs over selected plots, which reduced soil water potential to levels well below the permanent wilting percentage for plants (i.e. below -1.5 MPa). Even though a slight decrease in the abundance of P. nervosa (only found in the 0-5 cm soil layer) was recorded during the most severe drought stress (ca. -3.5 MPa), the majority of adult mites clearly survived these conditions for 3 weeks in the field without migrating to deeper soil layers. Exposing field collected adults in laboratory experiments simulating even more severe drought conditions revealed that P. nervosa can survive several weeks of gradually increasing drought stress (down to -7 MPa) with moderate water loss. The osmolality of body fluids increased as dehydration progressed, but apparently as a result of simple up-concentration of solutes and not the de novo synthesis of protective osmolytes. We compare and discuss these results in the light of what is known about other arthropods.

Suitability of Bemisia tabaci (Hemiptera: Aleyrodidae) biotype-B and Myzus persicae (Hemiptera: Aphididae) as prey for the ladybird beetle, Serangium japonicum (Coleoptera: Coccinellidae)Original article

Mi TIAN, Yuling WEI, Shize ZHANG, Tongxian LIU

Eur. J. Entomol. 114: 603-608, 2017 | DOI: 10.14411/eje.2017.073

The ladybird, Serangium japonicum (Coleoptera: Coccinellidae), is one of the most important predators of whiteflies in China, however, the suitability of different kinds of prey and nutritional requirements of this predator are poorly studied. The objectives of the present study were to investigate the pre-imaginal development, percentage survival of immatures, adult longevity and fecundity of S. japonicum when reared on two different species of prey, mixed ages of the cotton whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) biotype-B (i.e., eggs and nymphs) and green peach aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) in order to quantify their relative suitability as prey under laboratory conditions of 25 ± 1°C, 50 ± 10% RH and a photoperiod of 16L : 8D. The results of this study indicate that the total developmental period (from egg to adult) was shorter when they were fed on B. tabaci (18.29 ± 0.13 days) than on M. persicae (19.85 ± 0.22 days). The percentage survival of the immatures, growth index, development rate, adult fresh weight, fecundity and percentage of eggs hatching were higher and the pre-oviposition period was significantly shorter when S. japonicum were fed on B. tabaci than on M. persicae. In contrast, there was no significant difference in their longevity and oviposition period when fed on B. tabaci and M. persicae. The results indicate that as a diet for S. japonicum M. persicae is inferior to B. tabaci. This is the first record of S. japonicum being able to complete its development feeding exclusively on M. persicae. Since B. tabaci and M. persicae often simultaneously occur in vegetable fields, these results indicate that it is likely that S. japonicum could be utilized to control mixed populations of aphids and whiteflies, and furthers our understanding of ladybird population dynamics in the field in relation to the availability of different species of prey.

Climate-induced changes in the phenotypic plasticity of the Heath Fritillary, Melitaea athalia (Lepidoptera: Nymphalidae)Original article

Edit JUHÁSZ, Zsolt VÉGVÁRI, János P. TÓTH, Katalin PECSENYE, Zoltán VARGA

Eur. J. Entomol. 113: 104-112, 2016 | DOI: 10.14411/eje.2016.013

Recently a large number of studies have reported an increase in the variability in the climate, which affects behavioural and physiological adaptations in a broad range of organisms. Specifically, insects may be especially sensitive to climatic fluctuations, as their physiology and life history traits, like those of other ectotherms, are predominantly affected by environmental factors. Here we aimed to investigate climate-induced changes in several morphometric measures of the Heath Fritillary in North-Eastern Hungary, which is a highly diverse transitional area. During this study we tested the following hypotheses: (i) climate affects genitalia and body size to various degrees (ii) increasing variability in climate induces higher levels of fluctuating asymmetry and variance in all morphological characters. To our knowledge, this study is the first to analyse simultaneously wing size and structure of genitalia of a butterfly in response to variability in climate. Our findings suggest that wing and genital traits may exhibit similar degrees of stability in response to a more variable climate, although the response in terms of forewing size differs from that of other body measurements and the structure of the genitalia. These findings suggest that global climate change may affect lepidopteran body metrics over longer periods of time. Our findings parallel the results of investigations showing that insect morphology might be modified by environmental changes, which is especially the case for those body parts that are phenotypically very variable. However, we found no evidence that increasing variability in climate would induce higher levels of fluctuating asymmetry and greater variability in morphological characters.

Dragonflies and damselflies (Odonata) in urban ecosystems: A reviewReview

Giovanna VILLALOBOS-JIMÉNEZ, Alison M. DUNN, Christopher HASSALL

Eur. J. Entomol. 113: 217-232, 2016 | DOI: 10.14411/eje.2016.027

The expansion of urban areas is one of the most significant anthropogenic impacts on the natural landscape. Due to their sensitivity to stressors in both aquatic and terrestrial habitats, dragonflies and damselflies (the Odonata) may provide insights into the effects of urbanisation on biodiversity. However, while knowledge about the impacts of urbanisation on odonates is growing, there has not been a comprehensive review of this body of literature until now. This is the first systematic literature review conducted to evaluate both the quantity and topics of research conducted on odonates in urban ecosystems. From this research, 79 peer-reviewed papers were identified, the vast majority (89.87%) of which related to studies of changing patterns of biodiversity in urban odonate communities. From the papers regarding biodiversity changes, 31 were performed in an urban-rural gradient and 21 of these reported lower diversity towards built up city cores. Twelve of the cases of biodiversity loss were directly related to the concentrations of pollutants in the water. Other studies found higher concentrations of pollutants in odonates from built-up catchments and suggested that odonates such as Aeshna juncea and Platycnemis pennipes may be candidate indicators for particular contaminants. We conclude by identifying current research needs, which include the need for more studies regarding behavioural ecology and life-history traits in response to urbanisation, and a need to investigate the mechanisms behind diversity trends beyond pollution.

Northern geometrid forest pests (Lepidoptera: Geometridae) hatch at lower temperatures than their southern conspecifics: Implications of climate changeOriginal article

Julia FÄLT-NARDMANN, Tero KLEMOLA, Mechthild ROTH, Kai RUOHOMÄKI, Kari SAIKKONEN

Eur. J. Entomol. 113: 337-343, 2016 | DOI: 10.14411/eje.2016.043

Climate change may facilitate shifts in the ranges and the spread of insect pests, but a warming climate may also affect herbivorous insects adversely if it disrupts the locally adapted synchrony between the phenology of insects and that of their host plant. The ability of a pest species to colonize new areas depends on its ability to adjust the timing of phenological events in its life cycle, particularly at high latitudes where there is marked seasonality in temperature and day length. Here we incubated eggs of three species of geometrid moth, Epirrita autumnata, Operophtera brumata and Erannis defoliaria from different geographical populations (E. autumnata and O. brumata from Northern Finland, E. autumnata and E. defoliaria from Southern Finland and all three species from Germany) in a climate chamber at a constant temperature to determine the relative importance of geographic origin in the timing of egg hatch measured in terms of cumulative temperature sums (degree days above 5°C, DD5); i.e. the relative importance of local adaptation versus phenotypic plasticity in the timing of egg hatch. In all three species, eggs from northern populations required a significantly lower temperature sum for hatching than eggs from southern populations, but the differences between them in temperature sum requirements varied considerably among species, with the differences being largest for the earliest hatching and northernmost species, E. autumnata, and smallest for the southern, late-hatching E. defoliaria. In addition, the difference in hatch timing between the E. autumnata eggs from Southern Finland and Germany was many times greater than the difference between the two Finnish populations of E. autumnata, despite the fact that the geographical distances between these populations is similar. We discuss how these differences in hatching time may be explained by the differences in hatch-budburst synchrony and its importance for different moth species and populations. We also briefly reflect on the significance of photoperiod, which is not affected by climate change. It is a controller that works parallel or in addition to temperature sum both for egg hatch in moths and bud burst of their host plants.

Effect of temperature on rate of development, survival and adult longevity of Phthorimaea operculella (Lepidoptera: Gelechiidae)Original article

Stefanos S. ANDREADIS, Christos G. SPANOUDIS, Georgia ZAKKA, Barbara ASLANIDOU, Sofia NOUKARI, Matilda SAVOPOULOU-SOULTANI

Eur. J. Entomol. 114: 35-41, 2017 | DOI: 10.14411/eje.2017.006

The potato tuberworm, Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae), is a major pest of potato, Solanum tuberosum L. (Solanales: Solanaceae), both in the field and storehouses. The rate of development and survival of P. operculella, reared on potato tubers cv. Spunta at eight constant temperatures (17.5, 20, 22.5, 25, 27.5, 30, 32.5 and 35°C), were studied in the laboratory. The duration of development of the immature stages was recorded. Adult longevity was also recorded under the same conditions. Developmental time decreased significantly with increase in temperature within the range 17.5-32.5°C. No development occurred at 35°C. Survival (%) from egg to adult was higher at temperatures within the range 17.5-27.5°C than at either 30 or 32.5°C. Linear and a non-linear (Logan I) models were fitted to our data in order to describe the developmental rate of the immature stages of P. operculella as a function of temperature and estimate the thermal constant (K) and critical temperatures (i.e., lower developmental threshold, optimum temperature for development, upper developmental threshold). Lower developmental threshold and optimum temperature for development ranged between 12.5-16.2 and 31.7-33.8°C, respectively. The estimated upper developmental threshold for total immature development was 35.0°C. Thermal constant for total development was 294.0 degree-days. Adult longevity was significantly shorter at high (30 and 32.5°C) than at low temperatures (17.5-27.5°C). Our results not only provide a broader insight into the thermal biology of P. operculella, but also can be used as an important tool in planning an effective pest control program both in the field and storehouses.

Seasonal polyphenism in body size and juvenile development of the swallowtail butterfly Papilio xuthus (Lepidoptera: Papilionidae)Original article

Shinya KOMATA, Teiji SOTA

Eur. J. Entomol. 114: 365-371, 2017 | DOI: 10.14411/eje.2017.046

Seasonal polyphenism in adults may be a season-specific adaptation of the adult stage and/or a by-product of adaptive plasticity of the juvenile stages. The swallowtail butterfly Papilio xuthus L. exhibits seasonal polyphenism controlled by photoperiod. Adults emerging in spring from pupae that spend winter in diapause have smaller bodies than adults emerging in summer from pupae that do not undergo diapause. Pupal diapause is induced by short-day conditions typical of autumn. To explore the interactive effects of temperature and developmental pathways on the variation in adult body size in P. xuthus, we reared larvae at two temperatures (20°C, 25°C) under two photoperiods (12L : 12D and 16L : 8D). Pupal weight and adult forewing length were greater in the generation that did not undergo diapause and were greater at 25°C than at 20°C. Thus, body size differences were greatest between the individuals that were reared at the longer day length and higher temperature and did not undergo diapause and those that were reared at the shorter day length and lower temperature and did undergo diapause. Unlike in other Lepidoptera, larvae of individuals that undergo diapause had shorter developmental times and higher growth rates than those that did not undergo diapause. This developmental plasticity may enable this butterfly to cope with the unpredictable length of the growing season prior to the onset of winter. Our results indicate that there are unexplored variations in the life history strategy of multivoltine Lepidoptera.

Quametopia, a new genus of Nearctic Anthomyzidae (Diptera), with description of two new species, immature stages and life history

Jindřich ROHÁČEK, Kevin N. BARBER

Eur. J. Entomol. 108 (2): 287-326, 2011 | DOI: 10.14411/eje.2011.038

Quametopia gen. n. is established on the basis of recent phylogenetic analysis of taxa formerly assembled under the genus Mumetopia Melander, 1913 to include M. terminalis (Loew, 1863) and two new closely related Nearctic species of Anthomyzidae. The new genus is diagnosed and its phylogenetic relationships discussed. Quametopia terminalis (Loew, 1863) comb. n. is transferred from Mumetopia and redescribed based on revision of the type material (lectotypes of Anthophilina terminalis Loew, 1863 and its synonym Mumetopia nitens Melander, 1913 are designated) and other extensive material. Quametopia clintonia sp. n. and Q. amplistylus sp. n. (both from Canada, USA) are described and relationships of all three Quametopia species discussed. Immature stages of Q. terminalis and Q. clintonia sp. n. obtained by means of adult-to-adult rearing are described (1st- and 2nd-instar larvae for the first time in the family Anthomyzidae) and illustrated. Keys to adults, eggs, larvae and puparia of Quametopia species are presented. Biology (habitat and host-plant associations, life history) of Q. terminalis and Q. clintonia sp. n. are studied in detail and their ecological separation demonstrated. Distribution of all Quametopia species is reviewed.

Plant volatiles challenge inhibition by structural analogs of the sex pheromone in Lobesia botrana (Lepidoptera: Tortricidae)Original article

Albert SANS, Miguel MORÁN, Magí RIBA, Ángel GUERRERO, Jaume ROIG, César GEMENO

Eur. J. Entomol. 113: 579-586, 2016 | DOI: 10.14411/eje.2016.078

Plant volatiles can synergize the response to moth pheromone. Synthetic pheromone analogs, in turn, have the opposite effect in reducing pheromone attractiveness. To determine how these two types of stimuli interact and influence male moth behaviour, we performed wind tunnel experiments on the grapevine moth, Lobesia botrana. We noticed that a blend of host plant volatiles [(E)-β-caryophyllene, 1-hexanol, (Z)-3-hexenyl acetate and 1-octen-3-ol in a 100:20:10:5 ratio] significantly increased the response of males to an optimized blend of sex pheromone [(7E,9Z)-dodeca-7,9-dienyl acetate (E7,Z9-12:Ac), (7E,9Z)- dodeca-7,9-dienol (E7,Z9-12:OH) and (Z)-9-dodecenyl acetate (Z9-12:Ac)] in a 100:10:2 ratio. However, the response of males to the natural attractant was significantly reduced by two analogs [(9E,11Z)-tetradeca-9,11-dien-2-one (MK 2) and [(9E,11Z)-1,1,1-trifluoro-tetradeca-9,11-dien-2-one (TFMK 3)], of the major component of the sex pheromone of the insect (E7,Z9-12:Ac). When both stimuli were tested on males at pheromone:analog:plant volatile blend 1:100:1000 ratio, the plant blend offset the inhibitory effect induced by TFMK 3 but not that of MK 2. Our results show for the first time that under laboratory conditions plant volatiles can prevent inhibition by a pheromone analog.

Adaptive significance of the prolonged diapause in the western Mediterranean lycaenid butterfly Tomares ballus (Lepidoptera: Lycaenidae)Original article

Rafael OBREGÓN, Juan FERNÁNDEZ HAEGER, Diego JORDANO

Eur. J. Entomol. 114: 133-139, 2017 | DOI: 10.14411/eje.2017.018

Diapause is a common dormancy strategy exhibited by many species of invertebrates and insects to temporarily avoid seasonally recurring unfavourable conditions for their development, most usually in winter. Less frequently, a prolonged diapause lasting two or more years is described in species living in unpredictable environments where it is adaptive, but with significant costs. In this paper we examine the occurrence of prolonged diapause in the lycaenid butterfly Tomares ballus. Pupae of this species undergo an obligate diapause from mid-May to late January the following year. However, during our rearing experiments (from 2009 to 2016) the emergence of adults occurred sequentially and a fraction of the pupae remained in diapause for up to seven years. The annual percentage emergence after the first year of diapause was 45.6%, and only barely exceeded 50.0% in 2015. Remarkably, 12 pupae (11.4% of the initial brood) remained in diapause in their eighth year. The negative exponential equation fitted to the emergence data suggests that further emergences may occur within the next five years. Therefore, the potential for successful prolonged diapause of T. ballus pupae may be more than 10 years. The adaptive value of this strategy is discussed in relation to the effects of adverse and unpredictable weather during the flight period of the butterfly, intra-guild competition, parasitoids and changes in habitat quality. We suggest that this strategy may also be exhibited by other species of Mediterranean lycaenids.

Temperature-dependent functional response of Nesidiocoris tenuis (Hemiptera: Miridae) to different densities of pupae of cotton whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae)Original article

Mohammad Ali ZIAEI MADBOUNI, Mohammad Amin SAMIH, Peyman NAMVAR, Antonio BIONDI

Eur. J. Entomol. 114: 325-331, 2017 | DOI: 10.14411/eje.2017.040

The effect of temperature on the functional response of female adults of Nesidiocoris tenuis Reuter to different densities of Bemisia tabaci (Gennadius) pupae was assessed. Three constant temperatures (15, 25, and 35°C) and six prey densities (5, 10, 20, 35, 50, and 70) were tested over a 24-h period. Nesidiocoris tenuis exhibited a type II functional response at 15 and 25°C, and a type III response at 35°C. The number of prey consumed by the predator increased with increase in the prey density at all temperatures. Temperature influenced attack rates and handling times. The highest attack rate occurred at 35°C at high densities (35, 50, and 70 prey) and the lowest handling time was recorded at 35°C. The maximum attack rates (T/Th) were 17.13, 42.12, and 45.07 whitefly pupae per day at 15, 25 and 35°C, respectively. As a result, the value of a/Th indicates that N. tenuis was relatively more efficient in attacking B. tabaci at 35°C than at lower temperatures. Results suggest that the ability of N. tenuis to detect and consume B. tabaci over a broad range of temperatures, especially high temperatures (25-35°C), makes this mirid a good candidate for the biological control of whiteflies in warm environments, such as greenhouses.

Seasonal changes in bruchid (Coleoptera: Chrysomelidae: Bruchinae) assemblages along managed highway ecotonesOriginal article

Árpád SZENTESI, Zoltán GYÖRGY, Tibor JERMY, Balázs KISS

Eur. J. Entomol. 114: 488-499, 2017 | DOI: 10.14411/eje.2017.062

Spring and summer composition and species richness of bruchid pre-dispersal seed predator assemblages associated with species of leguminous plants were monitored in a four-year non-experimental survey of 32 service areas along five highways in Hungary. The vegetation bands along highways (delimited by fences) were considered a special type of ecotone where herbaceous plants are exposed to regular mowing and therefore the composition of the vegetation there is very different from the adjacent vegetation. Altogether 57 herbaceous and woody species of leguminous plants were recorded at these sites, harbouring 20 autochthonous, 3 allochthonous, but established, and 4 recently introduced species of bruchid seed predators (Coleoptera: Chrysomelidae: Bruchinae). The species of leguminous plants recorded along highway verges during this project make up approximately one fourth of the Fabaceae in Hungary and of the bruchids ca. 80 % (!) of the species known to occur in Hungary. At half of the service areas, mowing decreased the species richness of leguminous plants compared to that recorded prior to mowing, but not that of their bruchid seed predators. However, the species composition of the bruchid assemblages before and after mowing changed substantially. Null-model analyses indicated a random organization of spring assemblages and a deterministic one of summer assemblages of bruchids; very likely a result of host-specificity constraints. Calculations of host specificity confirmed the narrow host range recorded for bruchids that emerged from the samples of plants, in spite of new host records, such as three and two Trifolium species for Bruchidius picipes and Bi. sp. prope varius sensu Anton, respectively, Oxytropis pilosa for Bi. marginalis and Vicia cracca for Bruchus brachialis. Our results show that a surprisingly high number of species of bruchids occur in highway margins, however, the management of the vegetation there prevents a substantial portion of the native bruchid fauna establishing permanent populations.

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