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Variation of thorax flight temperature among twenty Australian butterflies (Lepidoptera: Papilionidae, Nymphalidae, Pieridae, Hesperiidae, Lycaenidae)Original articleGabriel NÈVE, Casey HALLEur. 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. |
Seasonal variability in the response of ground beetles (Coleoptera: Carabidae) to a forest edge in a heterogeneous agricultural landscape in JapanAtsushi OHWAKI, Yohei KANEKO, Hiroshi IKEDAEur. J. Entomol. 112 (1): 135-144, 2015 | DOI: 10.14411/eje.2015.022 Understanding arthropod responses to forest edges is essential to understanding both the characteristics of agro-ecosystems and the potential ecosystem services provided by forests adjacent to farmland in heterogeneous agricultural landscapes. Seasonal difference in the responses of carabid beetles to forest edges was determined using transects that extended from the edge of the forest 22.5 m into the interior of a forest and 22.5 m into the meadow in three seasons, early summer, late summer and mid-autumn. The responses of carabids to the forest edge in terms of species richness and abundance differed significantly in the three seasons. The species richness and abundance peaked in the meadow 4.5 m from the edge and were low in the forest in summer, whereas they peaked at the edge and remained high in the forest in autumn. Species-level analyses revealed that several species did not move between habitats, indicating that the forest edge acted as a barrier for these species. Many species, however, peaked in the meadow near the edge and the distribution of one species along the meadow-forest transect changed with the seasons. Our results indicate that secondary forests are not an effective sources of predators of pests, but do function as overwintering sites for some species. Because many species that prefer open land hibernate in field boundaries and fallow fields, the quality and spatial configuration of these habitats is important. Furthermore, in terms of pest management the seasonal dynamics of not only carabid beetles but other beneficial arthropods such as spiders and parasitoids should be considered. |
Seasonal polyphenism in Eristalis pertinax (Diptera: Syrphidae)Original articleLukasz E. MIELCZAREK, Andrzej OLEKSA, Katarzyna MEYZA, Adam TOFILSKIEur. J. Entomol. 113: 489-496, 2016 | DOI: 10.14411/eje.2016.064 Eristalis pertinax varies seasonally, with the spring morph more hairy than the summer morph. We measured the size and the venation of the wings of the seasonal morphs. Wings of the spring morph were significantly larger than those of the summer morph and those of females were larger than those of males. There were also significant differences between the morphs in wing venation and their allometric relationship. The differences between sexes were larger than differences between seasonal morphs. The allometry can account for the sexual dimorphism but not seasonal dimorphism. The differences between seasonal morphs in wing shape were relatively large with very few intermediate individuals. The differences were comparable to those between two related species of Syrphidae. Genetic analyses based on markers in nuclear and mitochondrial genomes unequivocally revealed that spring and summer morphs of E. pertinax form a single population and should not be regarded as separate taxa. Thus seasonal variability in this species is a rare example of polyphenism in Diptera. |
BOOK REVIEW: Muniappan R., Reddy G.V.P. & Raman A.: Biological Control of Tropical Weeds using Arthropods.M. SKUHRAVÁEur. J. Entomol. 108 (2): 331-332, 2011 | DOI: 10.14411/eje.2011.040 Cambridge University Press, Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo, Delhi, 2009, 495 pp. ISBN 978-0-521-87791-6. Price: GBP 75.00. |
Introducing barley as aphid reservoir in sweet-pepper greenhouses: Effects on native and released hoverflies (Diptera: Syrphidae)Ana PINEDA, María ÁNGELES MARCOS-GARCÍAEur. J. Entomol. 105 (3): 531-535, 2008 | DOI: 10.14411/eje.2008.070 Habitat management is a form of conservation biological control, that includes strategies such as the provision of alternative prey for natural enemies. One example is the "banker plants" strategy, which consists of introducing cereals with aphids in horticultural crops. It is usually combined with parasitoid releases. In this work we evaluated whether aphid-infested barley as "banker plants" enhances native populations of aphidophagous syrphids and extends the residence time of Episyrphus balteatus (De Geer) following release. The work was performed in four replicated sweet-pepper commercial greenhouses in the southeast of Spain. Barley was sown, and infested with the aphid Rhopalosiphum maidis (Fitch). Visual censuses were performed to record released individuals of E. balteatus (marked on the thorax before release) and naturally occurring hoverflies. At the end of the experiment leaf samples were taken to the laboratory, and the immature syrphids were reared for identification. The occurrence of syrphids that come from outside the greenhouse was significantly increased by the presence of the infested barley plants. From a total of 506 observations of adult native syrphids, 81% were Sphaerophoria rueppellii (Wiedemann). We did not find significant differences between control plots and those provided with banker plants in their probabilities to retain released specimens of E. balteatus. Of the syrphids collected at immature stages from the barley leaves, we did not record any E. balteatus, and 100% of the specimens were identified as S. rueppellii. We conclude that the banker plant strategy is effective in attracting natural populations of syrphids into sweet pepper greenhouses, but not in keeping released individuals of E. balteatus in the greenhouses long enough to lay eggs. We suggest that the E. balteatus release method should be amended. |
Reproductive status of Tribolium castaneum (Coleoptera: Tenebrionidae) affects its response to infection by Steinernema feltiae (Rhabditida: Steinernematidae)Original articlePaulina KRAMARZ, Dariusz MA£EK, Maria GAWE£, Szymon M. DROBNIAK, Joanna HOMAEur. J. Entomol. 113: 309-314, 2016 | DOI: 10.14411/eje.2016.039 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. |
Effects of diet on development and reproductive fitness of two predatory coccinellids (Coleoptera: Coccinellidae)Mohammad A. MIRHOSSEINI, M. Reza HOSSEINI, M. Amin JALALIEur. J. Entomol. 112 (3): 446-452, 2015 | DOI: 10.14411/eje.2015.051 Studies of prey suitability are needed to develop efficient mass rearing programs for generalist predators and to understand their potential contribution to integrated pest management. A laboratory study was conducted to evaluate the development and reproductive success of two predatory coccinellids, Oenopia conglobata (L.) and Cheilomenes sexmaculata (Fabricius), reared on diets of the common pistachio psyllid, Agonoscena pistaciae Burckhardt & Lauterer, the cotton aphid, Aphis gossypii (Glover) or a reference diet of Ephestia kuehniella Zeller eggs. Development and reproductive performance of the two coccinellids varied with diet, but egg fertility and immature survival did not. The developmental period (egg-adult) was shortest for both species on A. gossypii. This prey also yielded the shortest preoviposition period and greatest fecundity for C. sexmaculata. The psyllid diet was superior for reproduction in O. conglobata. For both predators, eggs of E. kuehniella were a better diet for development than for reproduction. Life table data indicated that the arboreal O. conglobata was better adapted to A. pistaciae on pistachio trees and might be a more effective biocontrol agent for this pest, despite the fact that C. sexmaculata had a higher intrinsic rate of increase on all diets. |
Mating alters the rate of development of ovarioles in the ladybird, Propylea dissecta (Coleoptera: Coccinellidae)Original articleMhd SHAHID, Arshi SIDDIQUI, OMKAR, Geetanjali MISHRAEur. J. Entomol. 113: 44-50, 2016 | DOI: 10.14411/eje.2016.005 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. |
Identification and expression pattern analysis of chemosensory receptor genes in the Macrocentrus cingulum (Hymenoptera: Braconidae) antennaeOriginal articleTofael AHMED, Tian-Tao ZHANG, Zhen-Ying WANG, Kang-Lai HE, Shu-Xiong BAIEur. J. Entomol. 113: 76-83, 2016 | DOI: 10.14411/eje.2016.009 Macrocentrus cingulum is an important polyembryonic endoparasitic wasp that attacks larvae of the Asian corn borer, Ostrinia furnacalis (Guenée) and the European corn borer, O. nubilalis (Hübner). Parasitoids use antennae as the main sensory organ to recognize herbivore-induced plant volatiles as host searching cues. The antennal olfaction proteins, odorant receptors (ORs) and ionotropic receptors (IRs) are involved in olfactory signal transduction pathway as a sensory neuron response. In the present study, we constructed a cDNA library from the male and female antennae for identifying the olfaction-related genes in M. cingulum. For that, we sequenced 3160 unique gene sequences and annotated them with gene ontology (GO), cluster of orthologous groups of proteins (COG), and KEGG ontology (KO). Through the homology search, we identified 9 odorant receptors (ORs), 3 ionotropic receptors (IRs) and 1 odorant binding protein (OBP) genes from the cDNA library sequences. Additionally, the expression patterns of these ORs and IRs in different tissues (antennae, heads, thoraxes, abdomens, and legs) were demonstrated by RT-PCR. The qualitative gene expression analyses showed that most of the OR genes were more highly expressed in female than male antennae; whereas IRs, unlike ORs, were more expressed in various male than females tissues. We are the first to report ORs and IRs in M. cingulum, which should help in deciphering the molecular basis of olfaction system in this wasp. |
Comparative efficiency of traps for horse fly (Diptera: Tabanidae) survey in riparian oak-ash forests in Danube floodplainOriginal articleAlma MIKU©KA, Selma MLINARIÆ, Lidija BEGOVIÆ, Erin CURRANEur. J. Entomol. 113: 531-536, 2016 | DOI: 10.14411/eje.2016.072 The objective of this work was to evaluate the relative trap efficiency of the three modified traps baited with 1-octen-3-ol as attractant, Box, Nzi and Canopy, for horse fly (Tabanidae) survey. Nine traps (three traps per trap type) were tested in 3 × 3 Latin square designs during summer 2011 in riparian oak-ash forests in the Danube floodplain of Croatia. Overall, the traps caught 1,986 specimens of 11 horse flies species during the study period. The most abundant species caught was Tabanus bromius (58%), followed by Tabanus tergestinus (21%), Tabanus maculicornis (16%), Tabanus sudeticus (2%), Atylotus loewianus (1%) and Tabanus autumnalis (1%). Both the Box traps and the Nzi traps had significantly greater catch efficiencies than the Canopy traps (βbox = 2.47, X2 = 65.48, df = 1, P < 0.001 and βnzi = 1.54, X2 = 25.12, df = 1, P < 0.001, respectively). Nzi traps had a catch rate 4.65 (95% CI: 2.55, 8.48) times greater than Canopy traps and Box traps had a catch rate 11.77 (95% CI: 6.48, 21.39) times greater than Canopy traps. Based on Shannon-Wiener diversity indices Nzi traps were better suited for diversity survey and had higher (H' = 1.33) indices than Box (H' = 1.08) or Canopy traps (H' = 1.00). |
Efficacy of semiochemical-baited traps for detection of Scolytinae species (Coleoptera: Curculionidae) in the Russian Far EastOriginal articleJon D. SWEENEY, Peter SILK, Vasily GREBENNIKOV, Michail MANDELSHTAMEur. J. Entomol. 113: 84-97, 2016 | DOI: 10.14411/eje.2016.010 Traps baited with plant volatiles and/or bark beetle pheromones have been used to survey for exotic and potentially invasive bark and wood-boring beetles in North America since the mid-1990s. Recent discoveries of sex and aggregation pheromones in the Cerambycidae offer means of improving detection rates of longhorn beetles, but little is known of their effects on detection of bark and ambrosia beetles in the subfamily Scolytinae. Our objectives were to determine the efficacy of host volatile trap lures for survey and detection of Scolytinae species and whether that efficacy was affected by the addition of longhorn beetle pheromones. More than 12,000 specimens and 36 species of Scolytinae were collected in two field trapping bioassays conducted in the Russian Far East in 2009 and 2010. The lure combination of spruce blend (a blend of racemic α-pinene, (-) β-pinene, (+)-3-carene, (+)-limonene, and α-terpinolene) and ethanol significantly increased detection rates and mean catches of Hylastes brunneus Erichson, Hylastes obscurus Chapuis, Ips typographus (L.), and Dryocoetes striatus Eggers compared with unbaited traps. The addition of the longhorn beetle pheromones, E-fuscumol, or E-fuscumol acetate, to traps baited with spruce blend and ethanol, slightly reduced mean catches of D. striatus but otherwise did not affect catch of any Scolytine species. Baiting traps with ethanol significantly increased mean catches of Anisandrus apicalis (Blandford), Anisandrus dispar (Fabr.), Anisandrus maiche (Kurenzov), Xyleborinus attenuatus (Blandford), Xyleborinus saxesenii (Ratzeburg), Xylosandrus germanus (Blandford), Scolytoplatypus tycon Blandford, and Trypodendron lineatum (Olivier). By themselves, the longhorn beetle pheromones, racemic hydroxyhexan-2-one and racemic hydroxyoctan-2-one, were not attractive to any Scolytine species. However, when added to ethanol-baited traps, hydroxyhexan-2-one lures significantly increased mean catch of S. tycon, hydroxyoctan-2-one lures significantly reduced mean catches of A. maiche and X. attenuatus, and lures of either hydroxyketone significantly reduced mean catch of T. lineatum. The lure treatments that detected the greatest number of species per sampling effort were spruce blend plus ethanol in 2009 (16 Scolytinae species and 13 species of Cerambycidae combined in an eight-trap sample) and hydroxyhexan-2-one plus ethanol in 2010 (20 Scolytinae species and 7 species of Cerambycidae combined in an eight-trap sample). Species accumulation curves did not reach an asymptote for any lure treatment, indicating that many species would go undetected in samples of 8-9 traps per site. |
Evaluation of pyriproxyfen, a juvenile hormone analog, on Drosophila melanogaster (Diptera: Drosophilidae): Insecticidal activity, ecdysteroid contents and cuticle formationFethi BENSEBAA, Samira KILANI-MORAKCHI, Nadia ARIBI, Noureddine SOLTANIEur. J. Entomol. 112 (4): 625-631, 2015 | DOI: 10.14411/eje.2015.084 The efficacy of pyriproxyfen, a juvenile hormone analog (JHA), was evaluated using third instar larvae of Drosophila melanogaster Meigen, 1830 (Diptera: Drosophilidae). Various doses of the compound, ranging from 0.01 to 2 ng/larva, were applied topically to larvae (12 h before pupariation). Treatment did not prevent pupariation but inhibited adult emergence at all the doses tested. In a second series of experiments the ecdysteroid content of pupae was determined following application of pyriproxyfen at two doses, 0.108 and 0.29 ng/larva, corresponding to ID25 and ID50, the doses required for 25 and 50% inhibition of adult emergence, respectively. Pyriproxyfen treatment increased the duration of pupal development. In addition, enzyme immunoassay measurements of ecdysteroids in whole body extracts of pupae indicated that pyriproxyfen decreased the ecdysteroid content in a dose-dependent manner. Finally, the effects on the cuticle of pyriproxyfen (ID50) were studied histologically, which revealed that this compound increased the thickness of the new adult cuticle and suppressed the formation of bristles. Biochemical analyzes revealed that an increase in chitin content of the cuticle is only recorded at the highest dose. Thus, a topical application of pyriproxyfen to third instar larvae interfered with the molting hormone and disrupted the normal development of this insect. |
Settling moths as potential pollinators of Uncaria rhynchophylla (Rubiaceae)NoteDaichi FUNAMOTO, Shinji SUGIURAEur. J. Entomol. 113: 497-501, 2016 | DOI: 10.14411/eje.2016.065 Nocturnal pollinators such as moths have received less attention than diurnal insects. To elucidate whether nocturnal moths are important pollinators, we observed both the diurnal and nocturnal visitors to the flowers of Uncaria rhynchophylla (Rubiaceae) in a warm-temperate forest in central Japan. The diurnal visitors included various taxonomic groups (e.g., bees, hoverflies and butterflies). The nocturnal visitors were exclusively moths (Geometridae, Erebidae, Noctuidae and Crambidae). Pollen grains of U. rhynchophylla were attached to both diurnal and nocturnal visitors. Although diurnal flower visitors carried pollen grains of other plant species, nocturnal moths did not carry heterospecific pollen grains. These results suggest that nocturnal moths, as well as diurnal insects, are important pollinators of U. rhynchophylla. |
Responses of grassland arthropods to various biodiversity-friendly management practices: Is there a compromise?Monika MAZALOVÁ, Jan ©IPO©, Stanislav RADA, Josef KA©ÁK, Boøivoj ©ARAPATKA, Tomá¹ KURASEur. J. Entomol. 112 (4): 734-746, 2015 | DOI: 10.14411/eje.2015.076 The rich species pool in semi-natural grasslands is associated with high spatial and temporal heterogeneity. This empirical study is one of the first to jointly analyze the response of orders, individual species and functional richness of arthropods to particular management practices and to linear landscape features, such as strips of grass and belts of trees. Mostly it was the less mobile, flightless taxa that were negatively affected by immediate disturbance caused by mowing. At a larger time-scale, grasslands managed by mowing once every year, and especially by a combined regime of mowing and grazing, supported the highest species richness of butterflies and beetles. Most functional diversity measures reached maximum values soon after mowing. Both strips of grass and belts of trees substantially affected the invertebrate community structure as the majority of taxa were positively associated with these linear features. Based on our results, we propose postponing mowing to later in the year, mowing in gradual stages, maintaining uncut strips primarily along permanent landscape features and establishing both strips of grass and belts of trees in submontane grassland environments. |
Host condition effects upon Agrilus planipennis (Coleoptera: Buprestidae) captures on decoy-baited branch trapsOriginal articleMichael J. DOMINGUE, Jennifer BERKEBILE, Kim STEINER, Loyal P. HALL, Kevin R. CLOONAN, David LANCE, Thomas C. BAKEREur. J. Entomol. 113: 438-445, 2016 | DOI: 10.14411/eje.2016.057 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. |
The effect of disturbance caused by rivers flooding on ground beetles (Coleoptera: Carabidae)Pawe³ SIENKIEWICZ, Micha³ ¯MIHORSKIEur. J. Entomol. 109 (4): 535-541, 2012 | DOI: 10.14411/eje.2012.067 We studied the effect of flooding on a carabid community inhabiting grassland in a large river valley (W Poland). We used pitfall-traps to catch beetles from April to November 1999-2001. Some of the samples collected were preceded by floods during the collecting period, which enabled us to evaluate the effects of flooding on species composition and abundance. We collected 17,722 individuals belonging to 108 species. The number of species and individuals per sample differed between plots and showed a nonlinear decrease over time, from spring to autumn. Carabids were more abundant in samples collected after floods than in the control samples. In contrast, the expected cumulative number of species as a function of the number of individuals collected was lower in samples collected after floods than in the control samples. In the case of the most abundant species the species-specific responses in terms of the numbers caught after flooding differed, with those of (e.g. Agonum micans) increasing and those of (Amara plebeja, Epaphius secalis) decreasing. This study shows that floods filter the community with the result that some species increase in abundance but the overall species richness decreases. Therefore natural floods are important in shaping the structure of communities of epigeic carabids on floodplains. |
Deterrence of feeding in Rhodnius prolixus (Hemiptera: Reduviidae) after treatment of antennae with a nitric oxide donorValeria SFARA, Eduardo N. ZERBA, Raúl A. ALZOGARAYEur. J. Entomol. 108 (4): 701-704, 2011 | DOI: 10.14411/eje.2011.089 The blood-sucking bug Rhodnius prolixus is the main vector of Chagas Disease in Colombia, Venezuela and several countries in Central America. Nitric oxide (NO) is a ubiquitous gaseous molecule present in most types of cell and participates in the olfactory pathway of insects. In this work, nitroso-acetyl-cysteine (SNAC), a nitric oxide donor, was topically applied to the antennae of fifth instar nymphs of R. prolixus. After SNAC treatment, these insects showed a dose-dependent reluctance to feed when provided with a living pigeon as the food source (ED50 = 5.2 µg/insect). However, there was no reluctance to feed when db-cGMP was applied to the antennae of nymphs. In another experiment, insects that had their antennae treated with SNAC were less attracted than the control group to a CO2 source. A possible role of NO in the olfactory pathway of R. prolixus is discussed. |
Ecological factors determining the density-distribution of Central European dragonflies (Odonata)Filip HARABI©, Ale¹ DOLNÝEur. J. Entomol. 107 (4): 571-577, 2010 | DOI: 10.14411/eje.2010.066 Habitat specificity is the most important factor affecting the regional distribution of dragonflies. Nevertheless, species with the highest specificity are not always the scarcest. Several important determinants of dragonfly density-distribution relationships were identified. Altitude preference and altitude range are significantly associated with dragonfly distribution. Some of the species that are habitat specialists but occur over a wide range of altitudes should be classified as rare but not endangered. This very simple principle is based on the assumption that habitat specialists have a very limited number of suitable biotopes. Obviously, dragonflies with a marginal distribution prefer a narrow range of altitudes (especially in terms of temperature limitation) and biotopes (effect of biogeography, marginality). Surprisingly, there is no "critical" life stage that is significantly associated with the regional distribution of dragonflies, although most species spend most time in the larval stage. Knowledge of the dispersal ability of particular species is limited, although it could significantly affect species survival and distribution. |
Differences in the nocturnal flight activity of insect pests and beneficial predatory insects recorded by light traps: Possible use of a beneficial-friendly trapping strategy for controlling insect pestsGang MA, Chun-Sen MAEur. J. Entomol. 109 (3): 395-401, 2012 The use of light traps for controlling insect pests is restricted since they kill both pests and beneficial insects. It may be a possible to reduce the numbers of beneficial insects trapped by adjusting nightly trapping time based on differences recorded in the timing of the nocturnal flight peaks of target pests and beneficials. To test this, insects were collected hourly over night using black light traps at three locations in China from 2003 to 2005. Groups of lepidopteran and coleopteran pests were selected as the target pests that we would control by trapping and groups of beneficial predatory insects the catches of which needed to be reduced. The highest numbers of Coleoptera were caught between 20:00 and 22:00 h and of most Lepidoptera between 02:00 and 04:00 h. The hourly numbers of predatory insects caught by light traps were evenly distributed throughout the night. A model was developed to describe the relationships between the cumulative proportions of insects caught and time of night. The model accurately describes the flight activity of insects that were mainly caught before midnight, after midnight and evenly throughout a night by using different parameters for the three different insect groups. A beneficial-friendly trapping strategy was developed to reduce the numbers of beneficial insects trapped, which was based on differences in the nocturnal flight activity of pests and beneficial insects and validated by a field study in Shandong province. Results show that this trapping strategy reduced the number of beneficial insects caught by 46% and the electricity consumption by 50% compared to the traditional strategy. Thus this strategy is more beneficial-friendly than the traditional trapping strategy for controlling pests. |
Prey preference and biomass consumption of Macrolophus pygmaeus (Hemiptera: Miridae) fed Myzus persicae and Macrosiphum euphorbiae (Hemiptera: Aphididae)Dionyssios P. LYKOURESSIS, Dionyssios C. PERDIKIS, Maria D. GASPARIEur. J. Entomol. 104 (2): 199-204, 2007 | DOI: 10.14411/eje.2007.031 The predation rate of the polyphagous predator Macrolophus pygmaeus (Rambur) when offered two aphid species, Myzus persicae (Sulzer) and Macrosiphum euphorbiae (Thomas), was investigated. Equal or unequal numbers of nymphs of each instar of the aphids were offered to the predator alone or together. Aphids were placed on an eggplant leaf, together with a fifth instar nymph of the predator in a plastic Petri dish and kept in growth cabinets at 25°C, 65 ± 5% r.h., and a 16L : 8D photoperiod. The predation rate of M. pygmaeus was always higher on M. persicae than on M. euphorbiae. However, biomass consumption was highest when instars of M. euphorbiae were offered in unequal numbers. The predator showed a strong preference and higher biomass consumption of first and second instar M. persicae. In tests where M. euphorbiae was the prey, preference and biomass consumption were almost always higher for the first instar. Therefore, first and second instar M. persicae and first instar M. euphorbiae provide optimal prey for M. pygmaeus. The implication of the prey preference shown by M. pygmaeus for the biological control of these two aphid species is discussed. |
Does the prediction of the time of egg hatch of Thaumetopoea processionea (Lepidoptera: Notodontidae) using a frost day/temperature sum model provide evidence of an increasing temporal mismatch between the time of egg hatch and that of budburst of Quercus robur due to recent global warming?Eiko WAGENHOFF, Annika WAGENHOFF, Rainer BLUM, Holger VEIT, Daniel ZAPF, Horst DELBEur. J. Entomol. 111 (2): 207-215, 2014 | DOI: 10.14411/eje.2014.030 Thaumetopoea processionea is a serious defoliator of oak and of medical concern whose abundance has consistently increased throughout Europe during the past two decades. This study validates a previously published frost day/temperature sum model for predicting time of egg hatch of this species using five years of recent field data from South-West Germany. This model proved satisfactory for predicting the time of egg hatch of T. processionea. Hence, the model was used to retrospectively predict the time of egg hatch of T. processionea in the Karlsruhe area, which indicates that the time of egg hatch has fluctuated over the past 130 years. In the last two decades, however, predicted time of egg hatch is much earlier than the long-term average due to the increase in winter and early spring temperatures. Comparison of predicted time of egg hatch of T. processionea and long-term records of the time of foliation of its common host Quercus robur revealed that in the study area the temporal advance in the timing of both events was similar. This is not in accordance with recently published research on spring-feeding folivores, which report a diverging trend in the timing of egg hatch and budburst of their host plants as a consequence of human-induced climate change. |
Morphological and molecular characterization of common European species of Adialytus (Hymenoptera: Braconidae: Aphidiinae) based on the mtCOI barcoding gene and geometric morphometrics of forewingsSa¹a S. STANKOVIÆ, Andjeljko PETROVIÆ, Marijana ILIÆ MILO©EVIÆ, Petr STARÝ, Nickolas G. KAVALLIERATOS, Vladimir ®IKIÆ, ®eljko TOMANOVIÆEur. J. Entomol. 112 (1): 165-174, 2015 | DOI: 10.14411/eje.2015.007 In this study three common European species of the genus Adialytus Förster, 1862 were examined: Adialytus ambiguus (Haliday, 1834), Adialytus salicaphis (Fitch, 1855) and Adialytus thelaxis (Starý, 1961). Molecular analysis involved the DNA barcoding of a region of the mitochondrial gene cytochrome oxidase I (COI). The genetic difference based on Kimura s two-parameter model for computing pairwise distances showed that A. thelaxis differs from both A. ambiguus and A. salicaphis by 4.9 and 6% on average, respectively. The genetic distance between A. ambiguus and A. salicaphis was 1.5% on average, suggesting that barcodes based on the COI gene are insufficiently informative for separating these two species. Geometric morphometrics analysis of forewing size and shape revealed statistically significant differences. The R1 vein on the forewing of A. ambiguus is more elongated than on the wings of A. salicaphis and A. thelaxis. The geometric morphometrics analysis of the forewings also revealed that A. salicaphis and A. thelaxis have much broader forewings, suggesting strong flight ability associated with their parasitizing arboricolous aphids. The distal part of the forewing of Adialytus ambiguus is narrower, which in this case suggests poor flight ability associated with parasitizing Sipha aphids on grasses. An illustrated key for identifying the European species of Adialytus is provided. |
Potential pollinator of Vanda falcata (Orchidaceae): Theretra (Lepidoptera: Sphingidae) hawkmoths are visitors of long spurred orchidKenji SUETSUGU, Koji TANAKA, Yudai OKUYAMA, Tomohisa YUKAWAEur. J. Entomol. 112 (2): 393-397, 2015 | DOI: 10.14411/eje.2015.031 Vanda falcata is a species of orchid native to China, Korea and Japan. While it is arguably one of the most celebrated orchids in Japan there is no information on its pollinators. Although most species of the subtribe Aeridinae, to which V. falcata belongs, have a short spur, V. falcata has a long spur. The results of the current study provide strong evidence that V. falcata is pollinated by long-tongued hawkmoths (Theretra spp.), which indicates that the evolution of long spurs in V. falcata could be an adaptation to pollination by long-tongued moths. |
Book review: Sonenshine D.E. & Roe R.M. 2013: Biology of Ticks. 2nd ed.D. SOJKAEur. J. Entomol. 112 (3): 564, 2015 | DOI: 10.14411/eje.2015.069 Sonenshine D.E. & Roe R.M. 2013: BIOLOGY OF TICKS. 2nd ed. Oxford University Press, New York. Vol. 1: ISBN 978-0-19-974405-3 (hard cover), 560 pp., price USD 133.00, GBP 97.00; Vol. 2: ISBN 978-0-19-974406-0 (hard cover), 496 pp., price USD 133.00, GBP 97.00. |
Inhibitory effects of plant extracts on growth, development and α-amylase activity in the red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae)Nujira TATUN, Boonguea VAJARASATHIRA, Jatuporn TUNGJITWITAYAKUL, Sho SAKURAIEur. J. Entomol. 111 (2): 181-188, 2014 | DOI: 10.14411/eje.2014.022 The bioinsecticidal effects of methanolic extracts of the leaves of castor bean, Ricinus communis, and papaya, Carica papaya, on the red flour beetle, Tribolium castaneum, were studied. More specifically, larval weight, larval mortality, percentage pupation, percentage adult emergence and F1 progeny production were recorded. We also studied the effects of the extracts on α-amylase activity and amylase gene expression in T. castaneum. The extracts of R. communis and C. papaya, which were administered in a diet, increased larval mortality and extended the durations of the larval and pupal periods. Feeding them an extract-treated diet also reduced the percentages of larvae that pupated and of adults that emerged and the number of F1 progeny. α-Amylase activity was inhibited and glucose content reduced in the larvae and adults of these insects. This inhibition of α-amylase activity by the R. communis and C. papaya extracts was concentration dependent in vitro. In addition, amylase gene expression was reduced in insects fed a diet containing C. papaya, but not R. communis extract. These results indicate that the bioinsecticidal effects of the leaf extracts are mediated by inhibiting the gene expression and activity of enzymes involved in sugar metabolism. |
Do egg parasitoids increase the tendency of Lestes sponsa (Odonata: Lestidae) to oviposit underwater?Filip HARABI©, Ale¹ DOLNÝ, Jana HELEBRANDOVÁ, Tereza RUSKOVÁEur. J. Entomol. 112 (1): 63-68, 2015 | DOI: 10.14411/eje.2015.017 The selection of oviposition sites by insects can significantly affect egg mortality. Spreadwing damselflies (Odonata: Lestidae) predominantly lay their eggs in parts of plants growing above the surface of water and only occasionally also those parts growing underwater. Factors affecting the choice of oviposition site and decision to lay underwater are still poorly understood. We examined whether localities with different risk of egg parasitism, different oviposition strategies (above or below the water surface) and the depth at which the eggs were laid, affected the total number of eggs laid, the proportion parasitized and egg mortality. In general, a significantly higher proportion of the eggs laid above the surface of water were parasitized but spreadwing damselflies showed significant preference for laying eggs underwater at both of the sites studied. This preference, however, had a different effect on the overall mortality of eggs at the two sites studied. Hence underwater oviposition by damselflies may be seen as a conditional anti-predator strategy, occurring only if the benefits exceed potential risks. Underwater oviposition may provide additional benefits other than protection against egg parasitism. |
Aphis pomi and Aphis spiraecola (Hemiptera: Sternorrhyncha: Aphididae) in Europe - new information on their distribution, molecular and morphological peculiaritiesRimantas RAKAUSKAS, Jekaterina BA©ILOVA, Rasa BERNOTIENĖEur. J. Entomol. 112 (2): 270-280, 2015 | DOI: 10.14411/eje.2015.043 Aphid species Aphis pomi (de Geer, 1773) is oligophagous on pomoideous host plants, whilst Aphis spiraecola Patch, 1914 is a polyphagous species alternating between Spiraea spp., its primary host, and a wide variety of secondary hosts, also including pomoideous species. Despite the biological distinction, these species are difficult to separate using their morphological characters. Partial sequences of mitochondrial COI and nuclear EF-1α genes were analyzed for samples from Central and Eastern Europe, Germany, Bulgaria, Italy, Turkey, China together with available data from GenBank. Interspecific pairwise sample divergences of the COI fragment ranged from 3.1 to 4.3%. One COI haplotype of A. pomi was predominant (n = 24), with a pan European distribution. The most abundant COI haplotype of A. spiraecola (n = 16) occurred in Lithuania, Latvia, Poland, Italy, Turkey and China. Interspecific pairwise sample divergences of the EF-1α fragment ranged from 0.6 to 1.2%. Analyzed partial sequences of EF-1α were identical in A. pomi. The most abundant EF-1α haplotype of A. spiraecola (n = 14) occurred in Lithuania, Poland, Italy, Turkey and China. The length of ultimate rostral segment appeared to be the most reliable morphological character for discrimination between apple and spirea aphid species. It allowed a 100% correct identification of A. pomi (n = 143) and 91.5% of A. spiraecola (n = 94) specimens in the European samples used for the molecular analysis. The existence of A. spiraecola in the Eastern Baltic region of Europe is documented for the first time. |
Suction sampling of grassland invertebrates using the G-vac: Quantifying and avoiding peripheral suction effectsAndrew CHERRILLEur. J. Entomol. 112 (3): 520-524, 2015 | DOI: 10.14411/eje.2015.058 Abstract. Suction sampling with modified garden leaf-blowers (G-vacs) is a widely used method for research on invertebrates in agricultural and grassland habitats. Approaches vary from sweeping the collecting nozzle across the surface of the vegetation within a known area, applying the nozzle firmly to the ground to delimit a sample area equal to nozzle crosssection, or applying the nozzle repeatedly within a larger open-ended cylinder placed on the ground. These approaches vary in potential for the inadvertent capture of specimens from outside of the sample area as a result of air being drawn into the nozzle from adjacent vegetation. This has never been studied adequately and is defined here for the first time as the Peripheral Suction Effect (PSE). Invertebrate species are likely to differ in susceptibility to PSE and so both sample size and composition could be impacted. This study compares two series of samples of Auchenorrhyncha taken using the same G-vac suction sampler (nozzle area, 0.01 m2) from areas enclosed and unenclosed by an open-ended cylindrical enclosure (area 0.17 m2) intended to prevent PSE. The unenclosed samples contained greater numbers of leafhoppers including Arthaldeus pascuellus, Javesella pellucida and immature Deltocephalinae. Numbers of immature Delphacinae did not differ between enclosed and unenclosed samples. The species composition of the two series of samples was similar, but the proportional representation of immature Delphacinae in unenclosed samples was diluted by the inflated numbers of other taxa that were drawn from the surrounding area. Peripheral suction effects are taxa-specific and therefore have the potential to bias measures of invertebrate community composition. Use of an open-ended cylinder to delimit the sample area is recommended as a simple, inexpensive and effective method of avoiding problems associated with PSE when using a G-vac. The potential for PSE with other models of suction samplers is discussed and questions for further research are identified. |
Species composition and dynamics in abundance of migrant and sedentary butterflies (Lepidoptera) at Gibraltar during the spring periodKeith J. BENSUSAN, Rebecca NESBIT, Charles E. PEREZ, Piotr TRYJANOWSKI, Piotr ZDUNIAKEur. J. Entomol. 111 (4): 555-559, 2014 | DOI: 10.14411/eje.2014.057 In order to understand patterns of abundances of migratory Lepidoptera in southernmost Europe and contrast this with those of sedentary species, we studied butterflies surveyed along transects during three spring migration seasons at the Rock of Gibraltar. Overall, 2508 butterflies belonging to 19 species were recorded. Of these, the four most numerous species accounted for almost 88% of all individuals recorded. These were the migratory Clouded Yellow Colias croceus, Red Admiral Vanessa atalanta and Painted Lady Vanessa cardui, and the sedentary Common Blue Polyommatus icarus. There was a significant correlation between abundance of P. icarus and C. croceus. Furthermore, abundances of C. croceus and V. atalanta were correlated. The sometimes very high abundance of migratory butterflies at the study site could suggest that Gibraltar is a stopover site for butterflies migrating between Africa and Europe. |
Hoverfly (Diptera: Syrphidae) richness and abundance vary with forest stand heterogeneity: Preliminary evidence from a montane beech fir forestLaurent LARRIEU, Alain CABANETTES, Jean-Pierre SARTHOUEur. J. Entomol. 112 (4): 755-769, 2015 | DOI: 10.14411/eje.2015.083 Hoverflies (Diptera: Syrphidae) provide crucial ecological services and are increasingly used as bioindicators in environmental assessment studies. Information is available for a wide range of life history traits at the species level for most Syrphidae but little is recorded about the environmental requirements of forest hoverflies at the stand scale. The aim of this study was to explore whether the structural heterogeneity of a stand influences species richness or abundance of hoverflies in a montane beech-fir forest. We used the catches of Malaise traps set in 2004 and 2007 in three stands in the French Pyrenees, selected to represent a wide range of structural heterogeneity in terms of their vertical structure, tree diversity, deadwood and tree-microhabitats. We assessed hoverfly assemblages by recording species richness, abundance and functional diversity. Malaise traps caught 2,374 hoverflies belonging to 104 species. The catches of hoverflies fluctuated both in species richness and abundance between 2004 and 2007. Strictly forest species were only caught in the most heterogeneous stand. Species strictly associated with fir were not recorded in the least heterogeneous stand although fir was present. Although most of the functional groups were recorded in the three stands, species richness, abundance and functional diversity decreased dramatically from the most heterogeneous to the least heterogeneous stand. However, the species assemblages in the less heterogeneous stands were not perfect subsets of that in the most heterogeneous stand, as some additional species not found in the most heterogeneous stand were also present. |



