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Results 541 to 570 of 2340:

Reproduction of the red mason solitary bee Osmia rufa (syn. Osmia bicornis) (Hymenoptera: Megachilidae) in various habitats

Monika FLISZKIEWICZ, Anna KU¦NIERCZAK, Bo¿ena SZYMA¦

Eur. J. Entomol. 112 (1): 100-105, 2015 | DOI: 10.14411/eje.2015.005

Osmia rufa L. (Osmia bicornis L.) is a species of a solitary bee, which pollinates many wild and cultivated plants. A total of 900 cocoons containing mature individuals of Osmia rufa L. (450 females and 450 males of a known weight), were placed in each of four habitats (orchard, mixed forest, hay meadow and arboretum of the Dendrology Institute of the Polish Academy of Sciences at Kórnik). These bees were provided with artificial nests made of the stems of common reed. The following parameters were calculated: reproduction dynamics, total number of chambers built by females, mean number of breeding chambers per reed tube and mean number of cocoons per tube. Included in the analysis were also the nectar flowers and weather conditions recorded in each of the habitats studied. General linear mixed models indicated that the highest number of chambers was recorded in the hay meadow (6.6 per tube). However, the number of cocoons per tube was similar in the hay meadow, forest and orchard (4.5-4.8 per tube) but was significantly lower in the arboretum (3.0 cocoons per tube on average). Also, the highest reproduction coefficient, 317.5%, was recorded in the hay meadows. Some nests were also parasitized and the highest mean number of infected chambers per tube (0.68) was recorded in the forest. The number of chambers was positively related to temperature. These results indicate that habitat had a significant effect on the reproduction of the red mason bee.

Life history of Amara fulva (Coleoptera: Carabidae) in the southwest forest zone of the East European Plain

Felix N. KOLESNIKOV, Ekaterina V. MALUEVA

Eur. J. Entomol. 112 (1): 127-134, 2015 | DOI: 10.14411/eje.2015.009

The patterns of seasonal activity, sex and age structure, reproductive characteristics and overwintering distribution of Amara fulva were studied in the southwest forest zone of the East European plain. A total of 1212 adults (664 males and 548 females) and 38 larvae were collected using pitfall traps. All adults were dissected to determine their reproductive condition. 185 larvae and 5 adults were collected by sampling soil. Adults of A. fulva were active from the first half of June until October with a single peak of activity in August. From June only postgenerative and newly emerged beetles were caught in traps. Immature and mature adults were recorded from the second half of July. At the end of August, more than 90% of the population was represented made up of mature adults. Immature individuals were trapped up until October after which they overwintered. Oviposition period lasted 11 weeks (from the mid-July to the end of September). Maximum number of mature eggs in ovaries was recorded in the second half of August. Larvae of A. fulva were caught from the second half of August to October and the peak in their subsoil activity was recorded in the first half of September. The life cycle of A. fulva is described as facultatively-biennial. Overwintering larvae and adults occurred in different parts of the floodplain. Larvae preferred to overwinter in soil under Persicaria maculosa near the edge of a river, while adults overwintered far from water and, rarely under tussock grasses on sandbars. The larvae of A. fulva cache the seeds of P. maculosa. Rearing A. fulva under field conditions revealed that this species takes 254-328 days complete its development, which includes the winter period.

Immunochemical detection of the crustacean cardioactive peptide in the cephalic ganglia of cockroaches (Blattodea: Blattidae)

Marcin GLADYSZ, Joanna GUZIK, Hana SEHADOVÁ, Bartosz BARAN, Jadwiga BEMBENEK, Bogdan DOLEZYCH

Eur. J. Entomol. 112 (2): 235-244, 2015 | DOI: 10.14411/eje.2015.035

In insects, the crustacean cardioactive peptide (CCAP) is involved mainly in the regulation of ecdysis and is both a hormone secreted into the haemolymph and a neuromodulator or neurotransmitter in the nervous system. However, this peptide has only been recorded in the brains of a few species of insects. The present study examined the distribution of CCAP in the cephalic ganglia of the cockroach, Periplaneta americana, using two kinds of specific antibodies. The antibody directed against synthetic CCAP detected a large number of CCAP-immunoreactive neurons in the protocerebrum, deutocerebrum, tritocerebrum, suboesophageal ganglion, optic lobes, frontal ganglion and neurohemal organs, while the antibody directed against CCAP precursor (pre-propeptide) stained only a few neurons within the central brain and frontal ganglion. The latter antibody also revealed similar sets of neurons in another species of cockroach, Gromphadorhina portentosa, and identified the CCAP precursor of approximately 15 kDa in size in Western blot analyses.

Preference of antlion and wormlion larvae (Neuroptera: Myrmeleontidae; Diptera: Vermileonidae) for substrates according to substrate particle sizes

Du¹an DEVETAK, Amy E. ARNETT

Eur. J. Entomol. 112 (3): 500-509, 2015 | DOI: 10.14411/eje.2015.052

Sand-dwelling wormlion and antlion larvae are predators with a highly specialized hunting strategy, which either construct efficient pitfall traps or bury themselves in the sand ambushing prey on the surface. We studied the role substrate particle size plays in these specialized predators. Working with thirteen species of antlions and one species of wormlion, we quantified the substrate particle size in which the species were naturally found. Based on these particle sizes, four substrate types were established: fine substrates, fine to medium substrates, medium substrates, and coarse substrates. Larvae preferring the fine substrates were the wormlion Lampromyia and the antlion Myrmeleon hyalinus originating from desert habitats. Larvae preferring fine to medium and medium substrates belonged to antlion genera Cueta, Euroleon, Myrmeleon, Nophis and Synclisis and antlion larvae preferring coarse substrates were in the genera Distoleon and Neuroleon. In addition to analyzing naturally-occurring substrate, we hypothesized that these insect larvae will prefer the substrate type that they are found in. Specifically, we tested substrate preference in a choice experiment for four species of antlions. This was then compared to the substrate that the larvae were naturally found in. Larvae of the four antlion species were allowed to choose among eight substrates differing according to their particle size. Our findings show that the majority of M. hyalinus larvae built pits in the finest sand fraction, and the majority of N. microstenus larvae were found in a coarser fraction. The other two species, M. immaculatus and E. nostras, constructed majority of their pits in a medium sand fraction. These results support the hypothesis that neuropteran larvae prefer specific substrates for pitbuilding or ambushing prey, and that this - in combination with other abiotic and biotic factors - may drive selection of appropriate habitats.

Parasitoids of the lime leaf miner Phyllonorycter issikii (Lepidoptera: Gracillariidae) recorded throughout the area it recently colonized

Levente SZÕCS, Melika GEORGE, Csaba THURÓCZY, György CSÓKA

Eur. J. Entomol. 112 (4): 591-598, 2015 | DOI: 10.14411/eje.2015.101

Phyllonorycter issikii (Lepidoptera: Gracillariidae) has recently spread over a considerable part of the Eurasian continent. So far, in Europe, unlike in Russia, it has not significantly affected its food plant (Tilia cordata), but its effect may increase over time. The regulating potential of associated parasitoid natural enemies is still low, which probably allows further leaf miner range expansion and population growth. This species is potentially capable of inflicting considerable damage on its host. Therefore, it is important to study its natural enemies, especially their oviposition behaviour and biology. In this paper, we summarize the results of rearing experiments throughout the area it has recently occupied, including our own study in Hungary. Here we list 46 species of parasitoids recorded from P. issikii. None of these species are likely to be able regulate the abundance of P. issikii. Further studies are needed to determine their effect on the abundance of this host.

Sociogenetic structure in nests of the mud dauber wasp Trypoxylon (Trypargilum) albitarse (Hymenoptera: Crabronidae)

Antonio C. BRAGATO BERGAMASCHI, Juliano DA COSTA ALMEIDA, Lucio A. DE OLIVEIRA CAMPOS, Marco A. DEL LAMA

Eur. J. Entomol. 112 (4): 722-727, 2015 | DOI: 10.14411/eje.2015.092

Trypargilum is a subgenus of solitary spider-hunting wasps whose males guard the nest, an unusual behaviour for male wasps. A male pairs with a female and copulates repeatedly with her during the nesting process, although females regularly copulate with satellite males, which employ an alternative reproductive strategy. The purpose of this paper was to determine the sociogenetic structure in twenty-nine nests of Trypoxylon albitarse sampled at six sites in Brazil. A total of 367 wasps were genotyped for eight species-specific polymorphic microsatellite loci. Genotypic segregation analyses were conducted to test whether the nests sampled were monogamic family groups. The results indicated that all the offspring in 12 of the 29 nests could be attributed to a single couple (genetic monogamy). Approximately 9% of the offspring probably resulted from extra-pair copulations and 3% of the total offspring were attributed to a second mother (usurpation by conspecific females, a form of intraspecific parasitism). The sequential replacement of parents throughout the nesting process indicates that the 29 nests analyzed included 35 family groups. Thus, our findings indicate that Trypoxylon albitarse has a predominantly monogamous genetic mating system, despite the social polygamy reported in previous studies.

Capsazepine affects thermal preferences of the American cockroach (Blattodea: Blattidae)Note

Justyna MALISZEWSKA, Eugenia TÊGOWSKA

Eur. J. Entomol. 113: 315-319, 2016 | DOI: 10.14411/eje.2016.040

Capsazepine is a competitive antagonist of capsaicin, a TRPV1 agonist responsible for the spicy taste of pepper. TRPV1 agonists and antagonists are known to affect mammalian body temperature, but their action on thermoregulation in insects is poorly known. In this study we evaluated the effect of capsazepine on the thermal preference of the American cockroach, Periplaneta americana using a thermal gradient. Our results revealed that capsazepine in submicromolar concentrations induces a preference for higher ambient temperatures when compared to the control insects. To assess whether capsazepine may act also as an antagonist of capsaicin in insects, we determined this insects' thermal behaviour when capsazepine was applied before capsaicin. The hypothermic response to capsaicin was clearly blocked by pre-treatment with capsazepine only in female American cockroaches. Our results indicate the involvement of structures functionally similar to TRPV1 in insect thermosensation.

Comparative efficiency of traps for horse fly (Diptera: Tabanidae) survey in riparian oak-ash forests in Danube floodplainOriginal article

Alma MIKU©KA, Selma MLINARIÆ, Lidija BEGOVIÆ, Erin CURRAN

Eur. 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).

Influence of natal host on parasitism by Spalangia cameroni (Hymenoptera: Pteromalidae)Original article

Francisco BEITIA, Erik VALENCIA, Bernat PERIS, Luis DE PEDRO, Josep D. ASÍS, José TORMOS

Eur. J. Entomol. 113: 99-103, 2016 | DOI: 10.14411/eje.2016.012

Spalangia cameroni Perkins (Hymenoptera: Pteromalidae) is sold commercially as a biocontrol agent of filth flies, including the house fly, Musca domestica L. (Diptera: Muscidae). For this reason, S. cameroni is mass-reared for inundative releases to control harmful flies. However, the mass-rearing protocols include very little information on the influence of natal host on subsequent host selection by parasitoids with more than one potential host as in the genus Spalangia. Here, we report on the use of S. cameroni against M. domestica. The S. cameroni were reared using Ceratitis capitata Wiedemann (Diptera: Tephritidae) (natal host) pupae for several generations. Freeze-killed fly pupae were used in assays to determine the fecundity, number of adult progeny and sex-ratio of this parasitoid. Realized fecundity and number of adult progeny were greater when provided with house fly pupae than Mediterranean fruit fly pupae. Thus S. cameroni parasitized more house fly pupae than C. capitata pupae, even though the parasitoid was reared on Mediterranean fruit fly for many generations. These results indicate that S. cameroni reared on C. capitata can be successfully used in inundative releases against both fruit flies (agriculture) and house flies (livestock farming).

Biology, affinity and description of an unusual aquatic new genus and species of Isotomidae (Collembola) from high altitude lakes in Tasmania

Penelope GREENSLADE, Mikhail POTAPOV

Eur. J. Entomol. 112 (2): 334-343, 2015 | DOI: 10.14411/eje.2015.032

A new species of Isotomidae (Collembola) was collected from submerged stones on the edge of nine lakes on Tasmania's Central Highland Plateau. Because it did not comply fully with the characters of any existing genus, a new genus, Chionobora gen. n. is erected for it here. An Antarctic species, Desoria klovstadi (Carpenter), has characters which conform with the new genus so is formally transferred to the new genus here. The Antarctic Continent and Tasmania were last in proximity 60 million years b.p. so it is suggested both species are relicts persisting in probable ice-free refugia during glacial cycles. Gut contents of specimens of the new species exclusively contained diatoms in various stages of digestion and the species appears to graze on aquatic macrophytes, a feeding habit not recorded before for Collembola. We note the high numbers of endemic invertebrate taxa of restricted distributions in cold habitats of southern regions compared to warmer regions and stress their conservation values and threats to their populations.

Effect of cold storage on the biological fitness of Encarsia sophia (Hymenoptera: Aphelinidae), a parasitoid of Bemisia tabaci (Hemiptera: Aleyrodidae)

Dawit KIDANE, Nian-Wan YANG, Fang-Hao WAN

Eur. J. Entomol. 112 (3): 460-469, 2015 | DOI: 10.14411/eje.2015.066

Encarsia sophia (Girault & Dodd) (Hymenoptera: Aphelinidae) is an important bio-control agent of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Storage at low temperature is a valuable method used in the mass rearing of biological control agents to ensure the availability of sufficient parasitoids when needed. However, storing parasitoids at a low temperature may lead to a decrease in their fitness. The aim of this study was to determine the effect of different durations of constant low temperature storage on the fitness traits of the above parasitoid. The effect of storage at three temperatures (4, 8 and 12 ± 1°C, RH = 65-75% and in darkness) for periods of 1, 2 or 3 weeks and at two pupal stages (10 and 12 days old) was studied. The percentage emergence, time to emergence, longevity, size and ability of the females that emerged to parasitize B. tabaci were evaluated. The results indicate that there is a decrease in percentage emergence, longevity and ability to parasitize the longer and lower the temperature at which the pupae of E. sophia are stored. The percentage emergence of both pupal stages kept at 12°C for a week was not affected. However, at lower temperatures (8 and 4°C) percentage emergence after storage of two weeks decreased to 67-87.5% and after three weeks none emerged. The time to adult emergence was longer for 12 day old pupae at all temperatures and storage times. The longevity of the adults that emerged from both pupal stages after one week of storage at 12 and 8°C was not affected, but decreased to 66-72% with increase in storage time. There was no effect of cold storage on adult size when 10 day old pupae were stored. The ability of this parasitoid to parasitize B. tabaci after emerging from both pupal stages stored at all of the temperatures regardless of storage time was significantly lower. Effect of storage at 12°C for a week in terms of percentage emergence and longevity did not differ from that of the control, but nevertheless they were less able to parasitize B. tabaci. Although the information on the effect of cold storage on E. sophia is very limited, the results of this study indicate that for more efficient biological control there is an urgent need to improve the method of storing pupae.

Size- and context-dependent nest-staying behaviour of males of the Japanese dung beetle, Copris acutidens (Coleoptera: Scarabaeidae)Original article

Mayumi AKAMINE

Eur. J. Entomol. 113: 207-211, 2016 | DOI: 10.14411/eje.2016.025

Male dimorphism in insects is often accompanied by alternative mating tactics, which may, together with morphological traits, determine fitness of the different male morphs. Fitness consequences of male head horn size, male-male competition and male nest-staying behaviour were experimentally assessed in Copris acutidens, in which major and minor males can co-occur in nests. Possible differences in their reproductive behaviour and breeding success were assayed in a breeding experiment, in which females were paired with one major male, one minor male, or a pair of major and minor males. The advantage of major males staying in a nest along with a rival male is that major males are reproductively more successful than minor males in this species. The weight of dung transported into nests was significantly less in rearing containers containing two males than in those with a single male of either morph, although it did not differ between major and minor males when kept alone. The results indicate that the presence of a rival male negatively affects male provisioning due to interference from rival males. In contrast, in the present study, an increased incidence of male nest-staying behaviour was recorded in the two- male and one minor male treatment than in the one major male treatment. These results indicate that because of the risk of sperm competition, major males stay longer in nests if a rival male is present. Furthermore, minor males (which are subject to a higher risk of sperm competition) stay longer than major males in nests without a rival male. In other words, the present study revealed an alternative behaviour during the post-copulatory stage associated with horn dimorphism and the presence or absence of a rival male.

Analysis of transcripts of heat shock protein genes in silkworm, Bombyx mori (Lepidoptera: Bombycidae)

Nalavadi CHANDRAKANTH, Kangayam M. PONNUVEL, Shunmugam M. MOORTHY, Sirigineedi SASIBHUSHAN, Vankadara SIVAPRASAD

Eur. J. Entomol. 112 (4): 676-687, 2015 | DOI: 10.14411/eje.2015.094

Silkworm is a poikilothermic insect, whose growth and development is significantly affected by high temperatures. The current study aimed to identify bivoltine breeds tolerant of the high temperature conditions that occur in the tropics. Percentage pupation at high temperatures and heat shock responses of silkworms were used as measures of thermotolerance. Thermotolerance of 20 silkworm breeds was assessed by rearing them at 36°C. Based on percentage pupation, three breeds, namely Nistari (multivoltine), SK4C (bivoltine) and CSR2 (bivoltine) were designated tolerant, moderately tolerant and susceptible, respectively. To understand the heat shock responses and the molecular mechanisms underlying thermotolerance, the tissue specific expression profiles of the nine heat shock protein (Hsp) genes were determined in the three breeds after a heat shock of 1 h at 36°C and a 2 h recovery period by performing real-time qPCR. The level of expression of Hsp genes was significantly increased in heat shocked tissues and gradually decreased during the recovery period. The greatest increase in the expression of Hsp genes was recorded in fat body followed by mid gut and silk gland. Of the three breeds, Nistari showed the highest expression of Hsp genes and SK4C a moderate expression relative to CSR2. The qPCR results showed that the transcript levels of sHsp20.4 and 20.1, and Hsp70 were increased by 10.3, 9.7 and 2.3 times, respectively, in Nistari compared to CSR2. Similarly the expression of sHsp20.4 and 20.1, and Hsp70 were increased by 3.5, 2.3 and 1.5 times, respectively in SK4C compared to CSR2. The expression levels of Hsps during heat shock corresponded to the percentage pupation recorded for the three breeds at a high temperature. It is suggested that the Hsps and their levels of expression may play an important role in increasing the survival of silkworm larvae at high temperatures. This study identified SK4C as a bivoltine breed, which is highly tolerant of high temperature measured in terms of percentage pupation (of the bivoltine breeds) and higher levels of expression of Hsp genes compared to CSR2. The importance of SK4C as a thermotolerant bivoltine parent for breeding new bivoltine hybrids tolerant of high temperatures is discussed.

Phylogenetic relationships and larval morphology of the recently described diving beetle genus Laccomimus (Coleoptera: Dytiscidae: Laccophilinae)

Mariano C. MICHAT, Mario TOLEDO

Eur. J. Entomol. 112 (4): 831-843, 2015 | DOI: 10.14411/eje.2015.085

The larvae of the diving beetle genus Laccomimus Toledo & Michat, 2015 (Laccophilinae) are studied for the first time, based on detailed descriptions and illustrations of all instars of L. distinctus Toledo & Michat, 2015, with particular emphasis on morphometry and chaetotaxy. The phylogenetic relationships of this genus within the tribe Laccophilini are analyzed cladistically. Laccomimus is recovered as part of a clade that includes the genera Australphilus Watts, 1978, Neptosternus Sharp, 1882 and Laccophilus Leach, 1815 and is characterized by the presence of natatory setae on the tibia and tarsus, and within this clade it is a sister to the other genera. Third-instar larvae of Laccomimus and Africophilus Guignot, 1948 share the mediodistal insertion of the seta CO7 on the meso- and metacoxa, a short and spine-like seta TI6 on the metatibia, a ventrally sclerotized abdominal segment V and a short urogomphus. These characters are considered plesiomorphic and indicate a basal position of both genera within the Laccophilini. All instars of Laccomimus are characterized by the anterolateral lobes of the frontoclypeus clearly projecting beyond the anterior margin and the last abdominal segment strongly elongated. Diagnostic features of the first instar are: frontoclypeus unmodified posteriorly, lamellae clypeales thin and hair-like, pores ANe, MXb-d-f-i, LAb-c and seta TR3 absent, seta LA3 and an additional dorsal pore present on the prementum, abdominal tergites I-VII with anterior transverse carina, and ventral surface of the abdominal segment VI sclerotized.

A comparison of the external morphology and functions of labial tip sensilla in semiaquatic bugs (Hemiptera: Heteroptera: Gerromorpha)

Jolanta BRO¯EK, Herbert ZETTEL

Eur. J. Entomol. 111 (2): 275-297, 2014 | DOI: 10.14411/eje.2014.033

The present study provides new data on the morphology and distribution of the labial tip sensilla of 41 species of 20 gerromorphan (sub)families (Heteroptera: Gerromorpha) obtained using a scanning electron microscope. There are eleven morphologically distinct types of sensilla on the tip of the labium: four types of basiconic uniporous sensilla, two types of plate sensilla, one type of peg uniporous sensilla, peg-in-pit sensilla, dome-shaped sensilla, placoid multiporous sensilla and elongated placoid multiporous sub-apical sensilla. Based on their external structure, it is likely that these sensilla are thermo-hygrosensitive, chemosensitive and mechano-chemosensitive. There are three different designs of sensilla in the Gerromorpha: the basic design occurs in Mesoveliidae and Hebridae; the intermediate one is typical of Hydrometridae and Hermatobatidae, and the most specialized design in Macroveliidae, Veliidae and Gerridae. No new synapomorphies for Gerromorpha were identified in terms of the labial tip sensilla, multi-peg structures and shape of the labial tip, but eleven new diagnostic characters are recorded for clades currently recognized in this infraorder. One synapomorphy is recorded for Hydrometridae + Hermatobatidae + Macroveliidae + Veliidae + Gerridae; five for Macroveliidae + Veliidae + Gerridae; one for Veliidae + Gerridae; and one for Gerridae alone. Within Gerridae, one possible autapomorphy is recorded for Trepobatinae, and two possible autapomorphies for Rhagadotarsinae. We also record a possible autapomorphy for Cylindrostethinae, which indicates that this taxon is monophyletic, as is indicated by other morphological characters. Finally, we record one putative diagnostic character for Macroveliidae + Veliidae, two families that are otherwise not considered sister groups. This new set of characters based on features of the mouthparts of gerromorphan bugs might provide new insights into the cladogenesis of the infraorder.

Benign neglect enhances urban habitat heterogeneity: Responses of vegetation and carabid beetles (Coleoptera: Carabidae) to the cessation of mowing of park lawns

Stephen VENN, D. Johan KOTZE

Eur. J. Entomol. 111 (5): 703-714, 2014 | DOI: 10.14411/eje.2014.089

In this study, we investigate the changes in both vascular plant and carabid beetle assemblages in response to reducing the intensity of management of park lawns in the city of Helsinki. Three levels of mowing were applied to patches of previously managed park lawns: (1) intensively mown, (2) mown until the previous season and unmanaged since, and (3) unmanaged for ten years (benign neglect). The lawns were dominated by plants that disperse vegetatively. This treatment gradient had little or no effect on the flight capability, feeding type or body-size of carabid beetles. However, there was an increase in species richness and the numbers of stenotopic species in the benign neglect treatment. We conclude that benign neglect of open grassland vegetation will result in higher levels of biodiversity than in more intensely managed vegetation. However, we consider it likely that the optimal strategy for maintaining urban biodiversity would be to apply a meadow management regime of mowing once or twice per year and leaving some areas of unmanaged grassland to maintain habitat heterogeneity.

A comprehensive study of the changes in ecdysteroid levels during the feeding phase of fifth instar larvae of the silkworm, Bombyx mori (Lepidoptera: Bombycidae)

Bela KESHAN, Bembem THOUNAOJAM, Sanathoibi D. KH

Eur. J. Entomol. 112 (4): 632-641, 2015 | DOI: 10.14411/eje.2015.088

The present study describes changes in haemolymph ecdysteroid levels during the feeding phase of fifth instar larvae of Bombyx mori. A small and sharp peak in ecdysteroid level was recorded on day 4 when larvae had already reached the critical weight (2.76 ± 0.11 g) for metamorphosis. Food deprivation of larvae from day 4 resulted in an increase in the ecdysteroid level. Injection of insulin in both 1 day (before reaching critical weight) and 4 day (after reaching critical weight) old fed larvae resulted in an increase in the ecdysteroid level. However, when deprived of food only the haemolymph ecdysteroid levels of 4 day old larvae respond to an injection of insulin. The hormone level was also increased by treating 1day old larvae with a juvenile hormone analogue, but again, like insulin, only the fed larvae were affected by this treatment. Neck- and thorax-ligated 4 day old larvae had decreased ecdysteroid levels compared to both fed and food deprived larvae. However, a significant increase in ecdysteroid level was recorded in both neck- and thorax-ligated larvae injected with insulin. The injection of 20-hydroxyecdysone into 4 day old larvae resulted in an increase in the level of this substance in the haemolymph of fed and food deprived larvae, but the level was significantly higher in neck- and thorax-ligated larvae. The data, thus, indicates that ecdysteroid levels vary both in relation to the critical weight of the larvae and its nutritional status, and insulin might also play an important role in regulating the level of ecdysteroid.

Cascading ecological effects caused by the establishment of the emerald ash borer Agrilus planipennis (Coleoptera: Buprestidae) in European Russia

Marina J. ORLOVA-BIENKOWSKAJA

Eur. J. Entomol. 112 (4): 778-789, 2015 | DOI: 10.14411/eje.2015.102

Emerald ash borer, Agrilus planipennis, is a destructive invasive forest pest in North America and European Russia. This pest species is rapidly spreading in European Russia and is likely to arrive in other countries soon. The aim is to analyze the ecological consequences of the establishment of this pest in European Russia and investigate (1) what other xylophagous beetles develop on trees affected by A. planipennis, (2) how common is the parasitoid of the emerald ash borer Spathius polonicus (Hymenoptera: Braconidae: Doryctinae) and what is the level of parasitism by this species, and (3) how susceptible is the native European ash species Fraxinus excelsior to A. planipennis. A survey of approximately 1000 Fraxinus pennsylvanica trees damaged by A. planipennis in 13 localities has shown that Hylesinus varius (Coleoptera: Curculionidae: Scolytinae), Tetrops starkii (Coleoptera: Cerambycidae) and Agrilus convexicollis (Coleoptera: Buprestidae) were common on these trees. Spathius polonicus is frequently recorded. About 50 percent of late instar larvae of A. planipennis sampled were parasitized by S. polonicus. Maps of the distributions of T. starkii, A. convexicollis and S. polonicus before and after the establishment of A. planipennis in European Russia were compiled. It is hypothesized that these species, which are native to the West Palaearctic, spread into central European Russia after A. planipennis became established there. Current observations confirm those of previous authors that native European ash Fraxinus excelsior is susceptible to A. planipennis, increasing the threat posed by this pest. The establishment of A. planipennis has resulted in a cascade of ecological effects, such as outbreaks of other xylophagous beetles in A. planipennis-infested trees. It is likely that the propagation of S. polonicus will reduce the incidence of outbreaks of A. planipennis.

Assessment of the quality of the terrestrial habitat of the threatened dragonfly, Sympetrum depressiusculum (Odonata: Libellulidae)Original article

Michal HYKEL, Filip HARABI©, Ale¹ DOLNÝ

Eur. J. Entomol. 113: 476-481, 2016 | DOI: 10.14411/eje.2016.062

The majority of the conservation strategies for threatened dragonflies are designed to protect only their aquatic habitats. Sympetrum depressiusculum is a species threatened not only by the destruction of its aquatic habitats but also by its association with a specific terrestrial environment. In this study, we aimed to identify the key elements of the terrestrial environment of adult S. depressiusculum. We used generalized linear mixed models to determine habitat preferences of adults and the particular features of habitat patches, such as vegetation cover, vegetation structure and the availability of potential prey. Our results indicate that S. depressiusculum adults preferred mainly riparian vegetation but beyond ponds they utilized only certain terrestrial habitats (abandoned fields, meadows, forest clearings). Adults responded positively to habitat patches with a high cover of vegetation and suitable vegetation structure. Adult abundance was affected also by the distance of patches from the natal site. In an agricultural landscape, the availability of such habitat patches may be limited and could influence the abundance and distribution of this species. We suggest that conservation efforts for this species should not only focus on the larval environment but also include suitable surrounding terrestrial habitats. Effective management around natal sites should concentrate on maintaining a heterogeneous landscape, which is extensively managed (e.g. leaving several fields fallow, maintaining managed hay meadows).

Seasonal variability in the response of ground beetles (Coleoptera: Carabidae) to a forest edge in a heterogeneous agricultural landscape in Japan

Atsushi OHWAKI, Yohei KANEKO, Hiroshi IKEDA

Eur. 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.

Cryoprotectant systems and cold tolerance of insects inhabiting central Yakutia (Russian Far East)Original article

Natalia G. LI

Eur. J. Entomol. 113: 537-541, 2016 | DOI: 10.14411/eje.2016.073

Strong tolerance of freezing is an important strategy for insects living in extremely cold regions. They produce highly effective cryoprotectant systems consisting of ice-nucleating proteins and polyols, which enables tolerable freezing of the body fluid. Therefore, the measurement of the concentrations of polyols and the activity of ice nucleators in the haemolymph is an essential tool for describing tolerance to ice formation in insects occurring in particularly cold places. This study evaluates three parameters: insect body supercooling point (SCP), haemolymph glycerol content and the profile of haemolymph ice nucleating activity that characterize the strategies of cold adaptation and cold hardiness in two previously unstudied beetles, Chrysolina graminis graminis L. and Galerucella nymphaea L., inhabiting Yakutia (Russian Far East, latitude 62°N). The high SCP values, ice nucleating activity and survival of the chrysomelids after freezing indicate that both species are tolerant of freezing. According to the profiles of ice-nucleating activity, the haemolymph from C. graminis graminis is characterized by a higher nucleating potential than that from G. nymphaea. The glycerol level is also higher in C. graminis graminis. The results indicate that both species develop tolerance to low temperatures, but the cold hardiness potential of C. graminis graminis is greater than that of G. nymphaea. This was revealed by the survival test, in which beetles were frozen to a temperature of -22°C for 30 min; 86% of C. graminis graminis and 72% of G. nymphaea survived the test. Thus, the freeze-tolerance of these beetles seems to be based on the production of an integrated cryoprotectant system, the quality of which apparently influences the range of their cold resistance.

The diversity of phoretic Mesostigmata on Ips typographus (Coleoptera: Scolytinae) caught in the Karkonosze forest

Dariusz J. GWIAZDOWICZ, Jacek KAMCZYC, Jerzy BLOSZYK

Eur. J. Entomol. 108 (3): 489-491, 2011

This study determined the scale of the phoresy of mesostigmatid mite by Ips typographus. Thirty pheromone traps in the Karkonosze National Park (Poland) caught 10,575 bark beetles on which there were 2,388 mesostigmatid mites belonging to eight species. The most numerous mites were Dendrolaelaps quadrisetus (1076 ind.) and Trichouropoda polytricha (1067 ind.).

An optimized method for mass rearing the tiger-fly, Coenosia attenuata (Diptera: Muscidae)

Joana MARTINS, Célia MATEUS, Ana C. RAMOS, Elisabete FIGUEIREDO

Eur. J. Entomol. 112 (3): 470-476, 2015 | DOI: 10.14411/eje.2015.059

The tiger-fly Coenosia attenuata Stein (Diptera: Muscidae) is a predator that is currently thought to be a useful biological control agent in greenhouses, especially in the Mediterranean region. Here, we present a method for rearing this predator in the laboratory by feeding it on fungus gnats (fed on Pleurotus ostreatus fungus) and drosophilids (Diptera). Over the past two years, this method has been continuously used to successfully produce predators for bioecological studies in the laboratory. Rearing cages with one, five or 10 male-female pairs, either of laboratory or field origin, were compared using females that were either unmated and recently emerged, or mated and about 20 days old (post-emergence). We evaluated the following parameters: number of rearing cages in which adults emerged, number and sex ratio of emerged adults, period from the introduction of parental pairs into cages and the emergence of the first offspring adults, and the period over which emergence occurred in the cages. Based on our results and in order to minimize the space needed for the colony, cages should be stocked with ca. 10 parental pairs, either of field or laboratory origin, with at least some mated females about 20 days post emergence. We also found that the predator's rearing substrate in the cages is improved if coconut fibre is mixed with the soil. These findings will improve the efficiency of C. attenuata rearing, an important step if it is to be used as a biological control agent.

Effect of three species of host tree on the cold hardiness of overwintering larvae of Anoplophora glabripennis (Coleoptera: Cerambycidae)Original article

Yuqian FENG, Reaxit TURSUN, Zhichun XU, Fang OUYANG, Shixiang ZONG

Eur. J. Entomol. 113: 212-216, 2016 | DOI: 10.14411/eje.2016.026

The Asian long-horned beetle, Anoplophora glabripennis, is a serious destructive pest of forests throughout China as it attacks a wide range of host plants. The effect of host trees on the cold hardiness of A. glabripennis larvae could be the basis for predicting the performance of this forest pest on different common hosts.To evaluate the effect of different species of host plant on the cold hardiness of overwintering larvae of A. glabripennis, we measured the supercooling point (SCP), fresh mass, protein content and concentrations of low molecular weight substances in overwintering larvae collected from three different host species (i.e., Populus opera, Populus tomentosa and Salix matsudana). Mean SCPs and protein contents of larvae from these three hosts differed significantly. The SCPs and protein contents of the larvae collected from P. opera and P. tomentosa were significantly higher than those collected from S. matsudana. The concentrations of glycerol, glucose and trehalose in overwintering larvae collected from these host species also differed significantly, but there were no significant differences in the concentrations of sorbitol and inositol. The larvae that were collected from S. matsudana had the highest concentrations of glycerol and trehalose and those from P. opera the lowest contents of glycerol, whereas those from P. tomentosa had the lowest concentrations of trehalose but the highest concentrations of glucose. Because of the significant differences in the quantities of these biochemical substances in their bodies, the cold hardiness of overwintering larvae of A. glabripennis was significantly dependent on the tree they fed on. These effects on the cold hardiness of the overwintering larvae might affect the selection of a host tree and therefore the spread of this beetle.

Organization of honeydew collection by foragers of different species of ants (Hymenoptera: Formicidae): Effect of colony size and species specificity

Tatiana A. NOVGORODOVA

Eur. J. Entomol. 112 (4): 688-697, 2015 | DOI: 10.14411/eje.2015.077

Aphid honeydew is one of the main energy sources for various ants in the temperate zone, nevertheless relatively little is known about the organization of the work of honeydew foragers (aphid milkers). This study focuses on the honeydew collecting strategies used by different ants in steppe and forest multi-species communities in Western Siberia. The behaviour of marked foragers of 12 species (Formica - 7, Lasius - 2, Camponotus - 1, Myrmica - 2) was recorded. Depending on the degree of the aphid milker specialization and degree of protection of the aphids five honeydew collecting strategies of various complexity were distinguished: unspecialized foragers in (I) "unprotected" aphid colonies (attended by ants < 60% of time) and (II) "protected" colonies (attended > 95% of time); (III) low "professional" specialization (ants "on duty" constantly attending aphid colonies); (IV) medium and (V) high "professional" specialization (clear division of tasks: honeydew collecting by "shepherds" and protection of trophobionts by "guards"; and honeydew transportation by "transporters" in V). Task specialization of the honeydew foragers is facultative: different ant taxa demonstrate a certain range of the honeydew collecting strategies of different complexities (Formica - I-V, Lasius - I-II, Camponotus - III, Myrmica - I-II) depending on the needs of their colony. The strategy used by ants did not depend on the species of aphid attended, but is strongly dependent on the species of ant, their colony size, available food resources and seasonality. In summer, the aphid milker specialization becomes more complex as ant colony size increases at both intra- and inter-specific levels and when food is scarce. In autumn Formica s. str. ants, which have the most advanced foraging strategy, adopt a simpler honeydew collecting strategy. Overall, the variety of honeydew foraging strategies seems to reflect the unequal contribution of different ants in forming trophobiotic interactions with aphids.

Partially disarticulated new Miocene burrower bug (Hemiptera: Heteroptera: Cydnidae) from Cerová (Slovakia) documents occasional preservation of terrestrial arthropods in deep-marine sediments

Peter VR©ANSKÝ, Jerzy A. LIS, Ján SCHLÖGL, Martin GULDAN, Tomá¹ MLYNSKÝ, Peter BARNA, Pavel ©TYS

Eur. J. Entomol. 112 (4): 844-854, 2015 | DOI: 10.14411/eje.2015.090

The state of preservation of the bug Sehirus carpathiensis J.A. Lis, Vr¹anský & Schlögl, sp. n. (Hemiptera: Heteroptera: Cydnidae) from the Lak¹árska Nová Ves Formation at Cerová (Slovakia) supports extremely rapid sinking and burial in upper bathyal Early Miocene sediments. The specimen originated from land at most a few kilometers away, but transport via a river can be excluded as the head and wings are still attached. Its most likely source based on fossil flora and the habitat of several living representatives of the genus is a riparian habitat in an adjacent area of land. Phylogenetically the new species is closely related to both Oligocene and living representatives of the genus, thus indicating an early Paleogene origin of the genus (like many other living insect genera). The observations based on two samples from one area (Czech Republic) indicate that terrestrial insects are occasionally preserved in deep marine environments, but overlooked due to their usually fragmentary and obscure nature of the preservation. The newly developed KVANT full-profile confocal measurement revealed a sample roughness Ra = 1.3-2.0 µm and abdomen submerged in the matrix 300 µm deeper than the more rigid pronotum.

Fast slide preparation for thrips (Thysanoptera) routine identificationsNote

Luís C.P. SILVEIRA, Marcelo M. HARO

Eur. J. Entomol. 113: 403-408, 2016 | DOI: 10.14411/eje.2016.052

Thrips are important agricultural pests and accurate identification is important for their effective management. In order to determine species, however, they need to be mounted on slides and the traditional process is time-consuming. The aim of this paper is to describe a simple and fast method to prepare temporary slides for the routine identification of thrips, which is not dependent on their colour and hardness. Four species of thrips of different colours were used in the preparations: Frankliniella occidentalis (yellow with brown tergal markings), Frankliniella schultzei (entirely brown), Haplothrips gowdeyii (dark brown to carmine) and Caliothrips phaseoli (brown to black). Slides of each species were prepared using three different methods: traditional (3 days), simplified (6 h) and fast method (10 min). The thrips on the resulting slides were observed under a microscope and important structures used in their identification were compared. The quality of the slides prepared using the traditional method was superior to those prepared using the other two methods if only the transparency and general position of the insects on the slides were considered. The transparency of the slides prepared using the simplified method was also good, but only for the pale coloured species (yellow and grey-brown). The fast method, on the other hand, was very efficient for routine identification since it resulted in slides of sufficient quality for identifying species regardless of their colour. It is important, however, to stress that the fast method is only suitable for preparing temporary slides for routine identification and is not a substitute for the traditional method of preparing permanent slides.

Feeding and oviposition behaviour of a gall inducing species of Glycaspis (Synglycaspis) (Hemiptera: Psylloidea: Aphalaridae) and development of galls on the leaves of Eucalyptus macrorhyncha (Myrtaceae) in central western New South Wales, Australia

Anamika SHARMA, Anantanarayanan RAMAN, Gary S. TAYLOR, Murray J. FLETCHER, Helen I. NICOL

Eur. J. Entomol. 112 (1): 75-90, 2015 | DOI: 10.14411/eje.2015.021

Glycaspis (Synglycaspis) confined to Australia includes gall-inducing and lerp-forming species that are probably highly specific to different species of Eucalyptus subgenus Eucalyptus. Based on available information, their distribution appears restricted to temperate, south-eastern and southern Australia. This paper reports the biology of an unnamed (suspected new species) of Glycaspis (Synglycaspis) that induces spherical, ostiolate galls on the leaves of Eucalyptus macrorhyncha in central western tablelands of NSW. This species completes two generations in a year. Oviposition elicits a passive response in the leaves of E. macrorhyncha. In this work we demonstrate that the host tissue not only supplies water, but also nutrients to the developing embryo via the embedded pedicel. Feeding action of the first instar initiates the gall and morphogenetic gradients become apparent around the feeding site. These gradients direct gall growth. The gall attains its near final spherical shape during the second instar and this spherical gall remains plugged with sugary material, which all the immature stages secrete from the last abdominal segment. No significant gall growth occurs during the occupation of the gall by the third, fourth and fifth instars. The first and second instars feed on the newly differentiated parenchyma tissue in galls, whereas the third, fourth and fifth instars feed on phloem of galls. Consequently the multi-layer parenchymatous nutritive tissue that initially develops lining the chamber dries and shrivels, when the later instars inhabit galls. This shrinkage induces a gradual thinning of gall walls, which is also aggravated by modest expansive growth of the gall.

Factors limiting the northern distribution of the blueberry maggot, Rhagoletis mendax (Diptera: Tephritidae) in Eastern CanadaOriginal article

Charles VINCENT, Pierre LEMOYNE, Sonia GAUL, Kenna MACKENZIE

Eur. J. Entomol. 113: 143-149, 2016 | DOI: 10.14411/eje.2016.018

Until recently, the Canadian distribution of the blueberry maggot, Rhagoletis mendax Curran (Diptera: Tephritidae), was restricted to Nova Scotia, Prince Edward Island and New Brunswick. The insect was first mentioned in southern Quebec in 1996 and, to date, it has not reached the Lac St-Jean region, where 34% of Canadian blueberry acreage is located. Two questions concerning the northern limit of distribution of the blueberry maggot in Quebec were addressed. First, are wild plants suitable hosts for larval development? We collected the fruit of five wild plants, (e.g. Vaccinium corymbosum, Vaccinium angustifolium, Vaccinium myrtilloides, Gaylussacia baccata, and Aronia melanocarpa) growing in southern Quebec and allowed larvae to complete their development into pupae. Blueberry maggot pupae were recovered from Vaccinium corymbosum, Vaccinium angustifolium, and Gaylussacia baccata, indicating that these plants are suitable for larval development. Second, are harsh winter temperatures a factor limiting the northern distribution of the blueberry maggot? Pupae collected in Quebec and Nova Scotia were put in the soil in the fall and were brought back to the laboratory to determine their supercooling points at different times during winter. The supercooling points of pupae collected in Quebec and Nova Scotia averaged -22.6°C. In natural conditions, air temperatures <-20°C are frequently observed in Quebec in January, February and March. However, due to snow cover, soil temperatures are rarely <-12°C. If -22.6°C constitutes the lower limit for the survival, then winter temperatures are probably not a limiting factor to its northern distribution in Quebec, because blueberry maggot pupae overwinter in the soil.

Electrophysiological and oviposition responses of Asian corn borer, Ostrinia furnacalis (Lepidoptera: Crambidae), to compounds rinsed from the surfaces of sugarcane and maize leaves

Xing-Chuan JIANG, Wen-Xia DONG, Bin CHEN, Chun XIAO, Fu-Rong GUI, Nai-Sheng YAN, Lei QIAN, Zheng-Yue LI

Eur. J. Entomol. 112 (2): 295-301, 2015 | DOI: 10.14411/eje.2015.042

The Asian corn borer, Ostrinia furnacalis, is one of the most important pests of maize (Zea mays) in China. However, the mechanism by which intercropping sugarcane (Saccharum officinarum) and maize controls this pest via compounds rinsed from leaf surfaces is still unclear. Electrophysiological and oviposition responses of the Asian corn borer to compounds rinsed from leaf surfaces of sugarcane and maize were studied. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses revealed that O. furnacalis responds to 21 compounds, which are present in both the compounds rinsed from leaf surfaces of sugarcane and maize. The effects of these compounds in concentrations of 5 × 10-3 g/mL or 5 × 10-4 g/mL on female oviposition behaviour were tested. They were attracted to oviposit on substrates coated with most of the test compounds, except nonanal. It is suggested that the compounds from the leaf surfaces of sugarcane induced O. furnacalis females to oviposit because most of them are similar to maize's leaf surface compounds, which results in a reduction in the number of egg masses laid on maize leaves.

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