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Results 961 to 990 of 2340:

Estimations of the critical temperatures for development of the pistachio psylla, Agonoscena pistaciae (Hemiptera: Psyllidae)

Mohammad Reza HASSANI, Abbas ARBAB, Hamzeh IZADI, Gadir NOURI-GANBALANI

Eur. J. Entomol. 108 (3): 403-407, 2011

The pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hemiptera: Psyllidae), is a major pest of pistachio trees throughout the pistachio producing regions in Iran. The effect of temperature on the developmental rates of eggs and nymphs of A. pistaciae was determined at different constant temperatures, i.e. 15, 20, 25, 30, 32.5 and 35 ± 0.5°C. The relationships between temperature and developmental rates were described by linear and the non-linear Lactin models. These models were evaluated based on R2, RSS, AIC and R2adj. The estimated value of the lower temperature threshold for egg, nymph and egg to adult development based on the linear model was 8.06, 10.38 and 9.97°C, respectively, and based on the Lactin model was 8, 11.55 and 11.2°C, respectively. Thermal constants estimated using the linear model, were 88.5, 243.90 and 333.33 DD, respectively, for egg, nymph and egg to adult development. These results indicate that the linear model gives a better description of the relationship between developmental rate and temperature for A. pistaciae than the non-linear model. These results could be incorporated into forecasting models used in the integrated pest management of this pest.

Genetic structure and phenotypic diversity of two northern populations of Cheilosia aff. longula (Diptera: Syrphidae) has implications for evolution and conservation

Vesna MILANKOV, Ljubinka FRANCUSKI, Jasmina LUDO©KI, Gunilla STÅHLS, Ante VUJIĆ

Eur. J. Entomol. 107 (3): 305-315, 2010 | DOI: 10.14411/eje.2010.039

The genetic structure and phenotypic diversity of two populations of Cheilosia aff. longula (Diptera: Syrphidae) in Lapland, Finland, were examined using DNA sequencing, protein electrophoresis, and geometric morphometrics. The morphological identification of the species were verified using partial sequences of mitochondrial cytochrome c oxidase subunit I (COI mtDNA), and the nuclear ribosomal internal transcribed region 2 (ITS2 rDNA), and comparing the corresponding sequences of Cheilosia aff. longula and the closely related C. longula. Two and three haplotypes of the genes COI mtDNA and ITS2 rDNA were identified in the two populations. Analysis of 12 isozyme loci showed an extremely low genetic variability in the populations originating from Utsjoki and Kevo. Discriminant analysis combined with canonical variate analysis revealed inter-population divergence in wing shape. Variation among genetically diverse individuals, both within- and among studied populations was studied, and directional (DA) and fluctuating asymmetry (FA) estimated using landmarks in the framework of geometric morphometrics. It is likely that the documented DA and FA asymmetry in both wing shape and size reflects the developmental instability of the individuals studied. By using Procrustes ANOVA the locations of particular landmarks responsible for the variation in shape were determined. The decomposition of the components of variance accorded to each landmark showed that the landmarks differed in the percentage of variation they accounted for (DA, FA and variation among individuals). In the discussion the implications of the reduced genetic diversity and asymmetry in wing traits for conservation is considered.

Genetic diversity, population structure and taxonomy of Calopteryx splendens (Odonata: Calopterygidae): An AFLP analysis

Saber SADEGHI, Tina KYNDT, Henri J. DUMONT

Eur. J. Entomol. 107 (2): 137-146, 2010 | DOI: 10.14411/eje.2010.019

Calopteryx splendens is a widely distributed palaearctic damselfly with a remarkably uniform morphology. Variation in the size and shape of the pigmented spot on the wing is the main diagnostic character used to discriminate subspecies across its huge geographic range. Here, AFLP analysis was used to assess the genetic structure and diversity of nine populations representing 3 putative subspecies and evaluate the pigment spot as a taxonomic marker. Genetic diversity was high, with the number of polymorphic loci per population ranging from 141 to 280 out of a total of 333 variable sites (42.3-84.1%) and Nei's gene diversity from 0.160 to 0.283 (overall 0.299). Overall population genetic differentiation (FST = 0.2766) suggests limited gene flow and adaptation to local environments. Restricted gene flow and genetic differentiation among populations are supported by significant FST estimates. High levels of gene flow (Nm >1) were only recorded among three Asian populations (Russia - Kazakhstan - Turkey). The patterns of genotypic diversity suggest that a given wing spot size and shape may arise from the hybridization of a limited number, possibly not more than four, ancestral gene pools in different ways and at different times. Clearly, the sample analyzed was not sufficient to capture all of the complex history of C. splendens, but sufficient to indicate the taxa ancilla, waterstoni, and orientalis possibly represent three of the four ancestral gene pools, and originated in western Asia. The origin of the fourth, xanthostoma, is the western Mediterranean.

Cohort-splitting in the millipede Polydesmus angustus (Diplopoda: Polydesmidae): No evidence for maternal effects on life-cycle duration

Jean-François DAVID, Jean-Jacques GEOFFROY

Eur. J. Entomol. 108 (3): 371-376, 2011

Under seasonal conditions, Polydesmus angustus individuals born in the first part of the breeding season have a 1-year life cycle and those born later have a 2-year life cycle (cohort-splitting). In this study, 249 juveniles from four early broods (born in mid-July) and four late broods (born in September) were reared under similar laboratory conditions, to test for possible maternal influences on life-cycle duration. Development times of early- and late-born individuals were compared under four combinations of day length and temperature (16 h - 18°C, 16 h - 16°C, 12 h - 18°C and 12 h - 16°C). The results showed that development time varied significantly in response to day length, temperature and sex, but that of individuals in the early and late broods did not differ significantly (mean development times ± SE: 180 ± 6 and 183 ± 8 days, respectively). There were no significant interactions between birth period and other factors, indicating that the effects of day length, temperature and sex on development time were similar in early- and late-born individuals. This indicates that the extended life cycle of millipedes born late in the season is not maternally determined and that cohort-splitting is controlled entirely by the environmental conditions experienced by the offspring during their development. This conclusion is supported by the absence of significant variation in offspring live weight at birth measured at different times in the breeding season. The results are discussed in relation to the bet-hedging theory, which is often put forward to account for cohort-splitting in arthropods. In P. angustus, the results are consistent with either bet-hedging or adaptive plasticity, but further studies are required to decide which interpretation is correct.

Parasitylenchus sp. (Tylenchomorpha: Allantonematidae) parasitizing field populations of Harmonia axyridis (Coleoptera: Coccinellidae)

Susanne HARDING, George O. POINAR, Desislava V. DIMITROVA, Tove STEENBERG

Eur. J. Entomol. 108 (3): 487-488, 2011

Adults of the invasive harlequin ladybird, Harmonia axyridis (Coleoptera: Coccinellidae), were found to be parasitized by nematodes (Tylenchomorpha: Allantonematidae) in Denmark. The nematodes were identified as Parasitylenchus sp. Major morphological characters of the nematodes did not differ significantly from Parasitylenchus coccinellinae Iperti & van Waerebeke 1968, but minor deviations in egg dimension and tail length were measured. Parasitism was only recorded in early autumn, with prevalence ranging from 2 to 33%. Adult and juvenile nematodes occurred together in the body cavity of both female and male H. axyridis.

Phylogenetic relationships of selected European Ennominae (Lepidoptera: Geometridae)

Erki ÕUNAP, Juhan JAVOI©, Jaan VIIDALEPP, Toomas TAMMARU

Eur. J. Entomol. 108 (2): 267-273, 2011 | DOI: 10.14411/eje.2011.036

This study reports the results of a molecular phylogenetic analysis of thirty three species of Ennominae (Lepidoptera: Geometridae). The aim of this analysis was to determine the phylogenetic affinities of 13 European species not previously studied using these methods. Fragments of seven nuclear genes, elongation factor 1 alpha (EF-1α), wingless (wgl), isocitrate dehydrogenase (IDH), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), ribosomal protein S5 (RpS5) and expansion segments D1 and D2 of the 28S rRNA gene and fragment of one mitochondrial gene, cytochrome oxidase subunit I (COI), were used. In the analysis using Bayesian phylogenetic inference, original gene sequences of the target species were combined with a larger data matrix of 20 species of Ennominae, used in a previous study (Wahlberg et al., 2010, Mol. Phylogenet. Evol. 55: 929-938). Most notably, the results indicate that the representatives of the genera Cepphis, Plagodis, Pseudopanthera and Selenia form a well-supported monophyletic group which appeared as the sister clade to the rest of the "ennomine" group of tribes. On the other hand, Crocallis and Opisthograptis group together with Ennomos. These results conflict with previous tribal subdivisions of the subfamily pointing to the need to reconsider the concepts of Ennomini and Ourapterygini. Within the tribe Macariini, the genus Macaria appears to be more closely related to Itame (= Speranza) than to Chiasmia clathrata. The emerging phylogenetic tree of Ennominae suggests only a limited phylogenetic inertia in body size making this group a promising target for comparative studies on this central life history trait and its correlates.

Systematics and biogeography of the Indo-Malaysian endemic Neochauliodes sundaicus species-group (Megaloptera: Corydalidae)

Xingyue LIU, Fumio HAYASHI, Oliver S. FLINT, Ding YANG

Eur. J. Entomol. 107 (3): 425-440, 2010 | DOI: 10.14411/eje.2010.050

The Neochauliodes sundaicus species-group is newly proposed, containing six species and endemic to Indo-Malaysia. All six species are described and illustrated, including two new species: Neochauliodes parvus Liu, Hayashi & Flint, sp. n. and N. peninsularis Liu, Hayashi & Flint, sp. n. Full species status is given to N. maculatus Stitz, 1914, stat. n. and N. borneensis van der Weele, 1909, stat. n. A cladistic analysis is conducted to reconstruct the species level phylogeny of the N. sundaicus group based on the morphological data. Combining the present morphological phylogeny and historical geography of Indo-Malaysia, the origin and speciation of this species-group is briefly discussed.

The mechanism of the emergence of Cotesia kariyai (Hymenoptera: Braconidae) larvae from the host

Yutaka NAKAMATSU, Toshiharu TANAKA, Jeffrey A. HARVEY

Eur. J. Entomol. 103 (2): 355-360, 2006 | DOI: 10.14411/eje.2006.047

At maturity, the endoparasitoid larvae of several subfamilies of the Braconidae have to emerge from inside of the host to pupate. Although the hosts hormonal milieu and the timing of larval parasitoid emergence have been studied, no report has yet focused on the physiological state of the host in connection with the emergence behavior of endoparasitoids. We investigated the mechanism of larval emergence behavior in a gregarious endoparasitoid, Cotesia kariyai. The parasitoid larvae inserted their mandibles into the host cuticle and perforated the integument by moving their head-capsule backwards and forwards. The emerging parasitoid larva must have a physical support (an "anchor") with the terminal appendages in order to exert the necessary pressure to cut the host integument. Morphological observations revealed that each parasitoid larva was enveloped in a capsule just before emerging from their host. Eight and nine day-old parasitoid larvae secreted material around their bodies to form these capsules. This material consisted of acid-glycoproteins which coated the exuvium of the 2nd instar larvae. The haemolymph volume of the parasitised host also decreased in later stages and was dramatically reduced immediatly prior to parasitoid emergence. This final reduction of the host haemolymph volume is the result of absorption by parasitoid larvae. This mechanism allows the parasitoid larvae to create an anchor more easily. The parasitoid larvae could also adhere to each other with the glycoprotein. In addition, these capsules prevent the leaking of host haemolymph through the emergence hole; these holes on the host integument were plugged by the capsules after parasitoid emergence. Although the pressure acquired by the anchor was lost once the head of the parasitoid larvae emerges from the host integument, the parasitoid larvae crawls out of the host cavity using backward pointing spines which enable the parasitoid to grip the capsule and move forward via peristaltic contractions.

The effect of prey availability on ovarian development and oosorption in the ladybird beetle Harmonia axyridis (Coleoptera: Coccinellidae)

Naoya OSAWA

Eur. J. Entomol. 102 (3): 503-511, 2005 | DOI: 10.14411/eje.2005.072

The ladybird beetle Harmonia axyridis Pallas was investigated under laboratory conditions to clarify the relationship between food abundance or scarcity and ovarian development or oosorption. Four conditions were used: (1) fully fed for 24 h, (2) 24-h starvation, (3) 48-h starvation, and (4) 24-h starvation followed by 24-h re-feeding. Body length and initial body weight were not significantly related to the number of ovarioles per female. Both starvation conditions significantly increased the percentage of oosorptive individuals and ovarioles per female, and significantly decreased the percentage of mature ovarioles per female. Re-feeding for 24 h after a 24-h starvation resulted in a significantly higher percentage of mature ovarioles per female; however, the percentage of mature ovarioles remained lower than in the fully fed condition. Oosorption mainly occurred during the intermediate developmental stage of the ovarioles. The rates of ovarian development and oosorption in predatory H. axyridis were much faster compared with those in herbivorous ladybird beetles. Body length, initial body weight, and the number of ovarioles were significantly correlated with the number of eggs laid during the last 24 h of each experimental condition. From an analysis of the weight loss and the number of eggs laid during the last 24 h of each experimental condition, it appears that the realized weight of the eggs may be directly determined by the amount of food digested by the adult. The ovarian development and oosorption were asymmetric in the right and left ovaries. These may be important strategies for oviposition in H. axyridis, because selective provision of maturing ovarioles in the right or left ovary with digested nutrients would favor their development. In addition, the energy loss through oosorption during the intermediate developmental stage of oocytes would be less than the energy loss resulting from the resorption of mature oocytes. Therefore, one role of the ovary in H. axyridis, in addition to egg production, might be as a kind of energy storage system for increasing reproductive success. An immediate start of ovarian development under favorable feeding conditions and rapid oosorption during food scarcities may be an adaptive ovipositional and survival strategy for female adults of H. axyridis in response to heterogeneous and fluctuating resource conditions.

Changes in the life history traits of the European Map butterfly, Araschnia levana (Lepidoptera: Nymphalidae) with increase in altitude

Kathrin D. WAGNER, Jochen KRAUSS, Ingolf STEFFAN-DEWENTER

Eur. J. Entomol. 108 (3): 447-452, 2011

Climatic conditions can modify the life history traits, population dynamics and biotic interactions of species. Therefore, adaptations to environmental factors such as temperature are crucial for species survival at different altitudes. These adaptive responses, genetically fixed or plastic (phenotypic plasticity), can be determined by physiological thresholds and might vary between sexes. The objective of this study was to determine whether the life history traits of the European Map butterfly (Araschnia levana) differ at different altitudes. A field experiment was carried out along an altitudinal gradient from 350 to 1010 m a.s.l. in a low mountainous region (Bavaria, Germany). 540 butterfly larvae were placed at different altitudes in 18 planted plots of their larval host plant, the stinging nettle (Urtica dioica). After three weeks the larvae were collected and reared under laboratory conditions. Developmental traits of the butterflies, mortality and percentage parasitism were measured. Larval development was generally slower at higher altitudes and lower temperatures and larval weight decreased with increasing altitude and decreasing temperature. However, there were no significant differences in pupation, adult lifespan and percentage mortality at the different altitudes and temperatures. Female larvae were heavier than those of males, and the pupal and adult lifespans were longer in females than in males. However, male and female butterflies reacted similarly to altitude and temperature (no significant interactions). None of the 188 larvae collected were parasitized. In conclusion, the phenotypic plasticity of European Map butterfly has enabled it to adapt to different temperatures, but the strategies of the sexes did not differ.

Variation in the colour of the necrophagous fly, Prochyliza nigrimana (Diptera: Piophilidae): A case of seasonal polymorphism

Daniel MARTÍN-VEGA, Arturo BAZ

Eur. J. Entomol. 108 (2): 231-234, 2011 | DOI: 10.14411/eje.2011.031

The occurrence of colour polymorphism in wild populations of the necrophagous fly Prochyliza nigrimana (Diptera: Piophilidae) is recorded but never treated in detail. The present paper shows that there is a seasonal distribution in the morphotypes, with the dark morphs emerging in spring and pale morphs emerging later and most abundant in summer. Furthermore, different proportions of each morph occur along altitudinal gradients, with dark morphs significantly more abundant at low altitudes, where mean temperatures are warmer than at high altitudes where the pale coloured morphs were more abundant. Explanations based on the adaptive value of thermal melanism are discussed.

Meiotic karyotypes and testis structure of 14 species of the planthopper tribe Issini (Hemiptera: Fulgoroidea, Issidae)

Valentina G. KUZNETSOVA, Anna MARYAŃSKA-NADACHOWSKA, Vladimir M. GNEZDILOV

Eur. J. Entomol. 107 (4): 465-480, 2010 | DOI: 10.14411/eje.2010.055

Karyotypes and testis structure of 14 species representing 9 genera (Latissus, Bubastia, Falcidius, Kervillea, Mulsantereum, Mycterodus, Scorlupaster, Scorlupella and Zopherisca) of the planthopper tribe Issini (Issidae) are presented. All the karyotypes are illustrated by meiotic and occasionally mitotic figures. The male karyotypes of most of the species analyzed are 2n = 26 + X, the exception being Falcidius limbatus, which has a karyotype of 2n = 24 + neo-XY. The latter is the first report of the neo-XY system in the family Issidae. The species studied are found to be similar in having NORs on the largest pair of autosomes, but differ significantly in the amount and distribution of C-heterochromatin along the chromosomes. In contrast to the conserved chromosome numbers, the highly variable follicle number in the testes suggests rapid evolution of the tribe Issini. On the basis of its specific follicle number, it is proposed that Zopherisca tendinosa skaloula Gnezdilov & Drosopoulos, 2006 be upgrade to a species: Z. skaloula stat. n. The cytological and taxonomic significance of results presented are discussed.

Aproceros leucopoda (Hymenoptera: Argidae): An East Asian pest of elms (Ulmus spp.) invading Europe

Stephan M. BLANK, Hideho HARA, József MIKULÁS, György CSÓKA, Constantin CIORNEI, Raoul CONSTANTINEANU, Irinel CONSTANTINEANU, Ladislav ROLLER, Ewald ALTENHOFER, Tomasz HUFLEJT, Gábor VÉTEK

Eur. J. Entomol. 107 (3): 357-367, 2010 | DOI: 10.14411/eje.2010.045

An invasive sawfly Aproceros leucopoda Takeuchi, 1939, which originates from East Asia, has colonized elms (Ulmus spp.) in Austria, Hungary, Poland, Romania, Slovakia and the Ukraine, at least since 2003. In Europe, the larvae can completely defoliate native and non-native elm trees and may cause at least partial dieback. Field observations indicate that elms are infested independent of their age and site characteristics. The life cycle of A. leucopoda is described based on material reared in Hokkaido, Japan. Parthenogenetic reproduction, short life cycle of summer generations and the ability to produce four generations per year result in the production of numerous progeny. The evolution of a seasonal dimorphism in head morphology, a simple cocoon that is attached directly to the host plant and a short period spent in the cocoon stage during summer, are putative apomorphies shared by Aproceros Takeuchi, 1939 and Aprosthema Konow, 1899. These traits reduce developmental costs and contribute to the proliferation of A. leucopoda. No specialized parasitoid, that can effectively reduce outbreaks of this species, is known. It is likely that this pest will spread into central and south-western Europe. Further monitoring of A. leucopoda is required to assess future range extensions in Europe, its exacerbating effect on Dutch elm disease and to find a suitable biocontrol agent. Concise keys to imaginal and larval stages are presented that will facilitate the identification of A. leucopoda.

Alternative foods for the multicoloured Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae)

Nick BERKVENS, Carmen LANDUYT, Koen DEFORCE, Dirk BERKVENS, Luc TIRRY, Patrick DE CLERCQ

Eur. J. Entomol. 107 (2): 189-195, 2010 | DOI: 10.14411/eje.2010.025

The multicoloured Asian lady beetle Harmonia axyridis (Coleoptera: Coccinellidae) may potentially exploit a range of "alternative" food sources. The nutritional value of three common non-prey food groups, i.e. fruit, fungi and pollen, is examined in this study. Development, reproduction and survival of the species were assessed in the laboratory on diets of apple, pear and raspberries and the fungi Oidium lycopersicum, Botrytis cinerea, Sclerotinia sclerotiorum and Rhizoctonia solani. When fed exclusively on these foods this ladybird failed to complete its development or reproduce. However, larval and adult survival was prolonged by 4 to 8 days and 55 to 67 days, respectively, when fruit was offered compared with only water. During a field study H. axyridis adults were collected monthly from March to October at two locations near Ghent, Belgium. Gut analysis demonstrated that, despite the continued presence of aphids, over 90% of all the adults collected contained pollen throughout the year. The pollen belonged to 53 different pollen types. Monthly average numbers of pollen grains in the gut varied from 5 to 233 grains. In contrast, there were about 35,000 grains in the guts of H. axyridis females that successfully developed and reproduced in the laboratory on diet that consisted of only pollen. This suggests that in the field in the majority of cases pollinivory mainly only provided complementary nutrients for this coccinellid. The use of alternative non-prey foods like pollen and fruit may play a role in sustaining populations of this coccinellid at times when the optimal prey is absent.

Thermal requirements of Trissolcus grandis (Hymenoptera: Scelionidae), an egg parasitoid of sunn pest

Shahzad IRANIPOUR, Zahra Nozad BONAB, John P. MICHAUD

Eur. J. Entomol. 107 (1): 47-53, 2010 | DOI: 10.14411/eje.2010.005

Trissolcus grandis is an important egg parasitoid of sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), the most serious pest of wheat in Iran. The thermal requirements of two populations of T. grandis were studied at five constant temperatures ranging from 20-32°C. Thermal thresholds for development were calculated using linear regression and degree-day models were determined by fitting non-linear equations to the data. The lower threshold for development was estimated to be 12.5 and 12.1°C, respectively, for males and females of the Bonab population, compared to 14.4 and 14.5°C for those of the Qaramalek population. Complete development required 143.8 and 162.8 degree-days, respectively, for males and females of the Bonab population and 116.9 and 124.6 for those of the Qaramalek population. Thus, wasps from the warmer region (Qaramalek) developed faster than those from the cooler region (Bonab), but had a higher thermal threshold for initiating development. Bonab females attained their highest fecundity (117.7 ± 7.2) at the lowest temperature tested (20°C), whereas the fecundity of Qaramalek females was maximal (96.8 ± 11.5) at 26°C. Biological control programmes that seek to augment wasp populations in wheat fields early in the spring, when natural rates of sunn pest parasitism tend to be low, should consider wasp thermal requirements to ensure the selection and release of locally-adapted parasitoids.

A review of the genus Zavrelia (Diptera: Chironomidae)

Torbjørn EKREM, Elisabeth STUR

Eur. J. Entomol. 106 (1): 119-144, 2009 | DOI: 10.14411/eje.2009.016

In this paper we review the taxonomy of the genus Zavrelia Kieffer, Thienemann & Bause and present emended generic diagnoses of all major life stages. Illustrated keys to larvae, pupae, adult males and females are presented as well as descriptions of four species new to science. Zavrelia species are only recorded from the northern hemisphere and comprise in total ten small to minute species. The following life stages and species are described: Larva, pupa, adult male and adult female of Zavrelia aristata sp. n., Zavrelia hudsoni sp. n., Zavrelia pentatoma Kieffer & Bause and Zavrelia sinica sp. n.; pupa and adult male of Zavrelia casasi sp. n.; and adult males of Zavrelia clinovolsella Guo & Wang and Zavrelia tusimatijea (Sasa & Suzuki). Zavrelia atrofasciata Kieffer and Stempellina paludosa Goetghebuer are proposed as new junior synonyms of Zavrelia pentatoma and lectotypes of Zavrelia nigritula, Zavrelia pentatoma and Stempellina paludosa are designated.

The effect of environmental conditions on diapause in the blister beetle, Mylabris phalerata (Coleoptera: Meloidae)

Fen ZHU, Fangsen XUE, Chaoliang LEI

Eur. J. Entomol. 103 (3): 531-535, 2006 | DOI: 10.14411/eje.2006.069

In the field, the blister beetle Mylabris phalerata Pallas (Coleoptera: Meloidae) undergoes larval diapause in the ground, which lasts for nearly six months. The effect of the soil environment on this diapause was examined. Final instar larvae kept at temperatures of >= 26°C do not enter diapause and continued to develop regardless of the soil water content and photoperiod. Below 25°C the final instar larvae entered diapause regardless of soil water content and photoperiod. The early stages, particularly L2, appeared to be more important for diapause induction than the later stages. However, the other instars were also sensitive. Temperature, rather then photoperiod was the main factor influencing pupal duration.

Does wing dimorphism affect mobility in Metrioptera roeselii (Orthoptera: Tettigoniidae)?

Dominik PONIATOWSKI, Thomas FARTMANN

Eur. J. Entomol. 108 (3): 409-415, 2011

Range shifts are among the most conspicuous effects of global warming. Marked changes in distribution are recorded both for highly mobile species of insects, which are capable of flight, and wing-dimorphic species with predominantly short-winged individuals. One of these species is the bush-cricket Metrioptera roeselii, which occasionally produces long-winged individuals. However, there is little known about the locomotory behaviour of wing-dimorphic insects. Yet to be able to predict potential range shifts it is necessary to know the dispersal potential of macropters. Therefore, an experiment was conducted in which individually marked M. roeselii were released at four sites. Different movement parameters, such as daily movement, activity radius, dispersal range, net displacement and crowding rate, were calculated. The statistical analyses showed that the movement of long-winged and short-winged individuals did not differ, but the percentage of individuals that were not seen again was twice as high for long-winged bush-crickets. These results suggest that most of the long-winged individuals that were seen again did not fly; i.e., they had the same basic mobility as the short-winged individuals. However, the comparatively low number of long-winged individuals that were seen again suggests that at least some macropters are long-distance dispersers, which is relevant for the dispersal process. The comparison of sexes showed that males were significantly more mobile than females. This sex-specific locomotory behaviour in M. roeselii might depend on a complex series of social interactions and physiological conditions.

"DNA barcoding" is of limited value for identifying adelgids (Hemiptera: Adelgidae) but supports traditional morphological taxonomy

Martina ®UROVCOVÁ, Jan HAVELKA, Petr STARÝ, Pavlína VĚCHTOVÁ, Daniela CHUNDELOVÁ, Andrea JARO©OVÁ, Lucie KUČEROVÁ

Eur. J. Entomol. 107 (2): 147-156, 2010 | DOI: 10.14411/eje.2010.020

The sequence diversity in the mitochondrial cytochrome-c oxidase I (COI) gene was evaluated as a tool for resolving differences among species of European adelgids collected from several localities across the Czech Republic. Members of 7 genera and 16 species were examined, and as outgroups, two species of Phylloxeridae were used. Sequence divergences within species were on average less than 0.15%, whereas divergences between species ranged from 0.0 to 4.12% for congeneric and to 13.24% for intergeneric comparisons. It is concluded that DNA barcoding of Adelgidae is a powerful tool for identifying genera, but at the species level it works only in those cases where there are no species complexes. Nevertheless, it can be used as a complement to traditional, morphological taxonomy.

The genus Microplinthus, with description of four new species (Coleoptera: Curculionidae: Molytinae)

Massimo MEREGALLI

Eur. J. Entomol. 101 (4): 609-627, 2004 | DOI: 10.14411/eje.2004.084

The genus Microplinthus Zherikhin, 1987 is revised. It is assigned to the tribe Aminyopini Voss, 1956, based on the female genitalia and the presence of appendiculate claws in one species. The following new species are described: M. parbatensis sp. n. (Central Nepal); M. kaligandaki sp. n. (Central Nepal); M. shiva sp. n. (India: Darjeeling); M. laurae sp. n. (India: Darjeeling; Sikkim; Central-western Nepal?). The genus is apparently the sister group to Falsanchonus Zherikhin, 1987. Mutual relationships among the nine species of Microplinthus are suggested based on a phylogenetic analysis.

A new species group and five new species of the genus Pavania (Acari: Dolichocybidae) associated with insects, with notes on leg chaetotaxy and the distribution of genera

Hamidreza HAJIQANBAR, Alexnder KHAUSTOV

Eur. J. Entomol. 107 (3): 441-453, 2010 | DOI: 10.14411/eje.2010.051

A new species group and five new species of mites of the genus Pavania Lombardini, 1949 belonging to the family Dolichocybidae (Acari: Heterostigmata) are described from Iran. Pavania gymnopleuri Hajiqanbar & Khaustov sp. n., P. sabzevarensis Hajiqanbar & Khaustov sp. n. and P. onthophagi Hajiqanbar & Khaustov sp. n., represent a new gymnopleuri species group. Two new species are also described in the fusiformis group: P. kamalii Hajiqanbar & Khaustov sp. n. and P. elongata Hajiqanbar & Khaustov sp. n. All new species are associated with scarabaeid and carabid beetles (Coleoptera: Scarabaeidae, Carabidae). This is the first record of the family Dolichocybidae from Iran. The leg setation and geographic distribution of all genera of this family are discussed and keys to genera and species of the genus Pavania are provided.

Habitat preferences influencing populations, distribution and conservation of the endangered saproxylic beetle Cucujus cinnaberinus (Coleoptera: Cucujidae) at the landscape level

Jakub HORÁK, Eva VÁVROVÁ, Karel CHOBOT

Eur. J. Entomol. 107 (1): 81-88, 2010 | DOI: 10.14411/eje.2010.011

Cucujus cinnaberinus (Scopoli, 1763) is a saproxylic beetle listed in the IUCN Red List and the European Habitats Directive. Although the species is highly protected and often red-listed little is known about its ecological requirements and status of its populations. Therefore, our main aims were to review its current and historical distributions and status of C. cinnaberinus populations in Europe and to determine its recent habitat preferences at the landscape level in the Czech Republic, where the increasing number of records over the last few years indicates a possible increase in abundance of this beetle. Cucujus cinnaberinus is closely associated with soft-wood and broad leaved trees and is able to colonize man-made habitats from persisting local populations if there is a sufficient supply of suitable dead wood. This beetle is not restricted to old-growth forests or even relict woodland, as previously reported, but currently predominantly inhabits abandoned planted stands of trees like lignicultures or avenues, which have an open canopy. Colonization of stands dominated by hybrid poplars probably resulted in the recent increase in the number of records of this species in the central European countries. However, this could present problems for the protection of this species in future, because the trees in these stands are gradually dying and are not being replaced. The decline and extinction of C. cinnaberinus on the northern and southern edges of its distribution was probably caused by the absence of soft-wooded broadleaved trees in intensively managed forests and other more suitable habitats.

The influence of yellow lupin intercropped with spring triticale on predatory carabid beetles (Coleoptera: Carabidae)

Michal HUREJ, Jacek P. TWARDOWSKI

Eur. J. Entomol. 103 (1): 259-261, 2006 | DOI: 10.14411/eje.2006.031

Intercropping may have a positive effect on the abundance and activity of carabid beetles and therefore their response to intercropping yellow lupin with spring triticale was studied for a period of three years (2001-2003). Carabids were most numerous in yellow lupin monoculture and in the intercrop with the highest proportion of lupin. Important differences between the experimental treatments were found, but they were mostly non-significant because of the great variation between samples. It is supposed that the positive effect of lupin on carabid beetles was due to the shelter it provides. During the three-year study 59 species of carabid beetles were recorded. The most abundant species in each treatment was Pseudoophonus rufipes. Irrespective of the experimental treatment, this species was caught in the greatest numbers towards the end of each growing season. This was probably because of the greater soil coverage provided by the larger lupin plants at the end of the season.

Past and present distribution of the cryptic species Leptidea sinapis and L. reali (Lepidoptera: Pieridae) in Poland and its implications for the conservation of these butterflies

Konrad SACHANOWICZ, Agnieszka WOWER, Jaroslaw BUSZKO

Eur. J. Entomol. 108 (2): 235-242, 2011 | DOI: 10.14411/eje.2011.032

Using a large sample of museum and newly collected specimens of the cryptic butterfly species Leptidea sinapis and L. reali, identified/confirmed based on genital characters, the patterns in their geographical distributions, historical changes in range and briefly also their habitat associations in Poland, were investigated. Leptidea sinapis occurs mainly in the lowland and upland parts of the country and is rarer than L. reali, which is widespread throughout Poland, including the mountains. In the first half of the 20th century, the range of L. sinapis included the whole of Poland, whereas currently it is confined to eastern and southern regions. Historical records of the distribution of L. reali are concentrated in southern and central Poland. Currently it is recorded from localities throughout Poland. Leptidea reali is recorded most frequently in meadows and shows no clear preference for a particular level of humidity, while L. sinapis is found mainly in woodland and xerothermic habitats. The two species are syntopic within the present range of L. sinapis, which is now a declining and local species, whereas L. reali is now common and widespread.

Re-evaluation of the genus Phonochorion (Orthoptera: Tettigoniidae: Phaneropterinae)

Hasan SEVGILI, Selim S. CAGLAR, Ismail K. SAGLAM

Eur. J. Entomol. 107 (4): 631-645, 2010 | DOI: 10.14411/eje.2010.072

Phonochorion Uvarov (Orthoptera: Tettigoniidae: Phaneropterinae) is a little known genus consisting of three species: Ph. satunini, Ph. artvinensis and Ph. uvarovi. The objective of this study is to conduct a thorough distributional, taxonomic and systematic revision of the genus Phonochorion using both bioacustic and external morphological characters. Field surveys indicate that the genus is distributed from the Trabzon region of Turkey to the Khulo province of Georgia however the exact limit of the eastern distribution of the genus remains unknown. Phonochorion species occur only on the northern slopes of the East Black Sea and Lesser Caucasus Mountains. The Coruh Valley, which seprates the East Black Sea and Lesser Caucasus Mountain ranges, seems to be an effective physical and climatic barrier and determines the distribution of these species. Ph. uvarovi can clearly be distinguished from Ph. satunini and Ph. artvinensis by the calling songs of males and external morphological characters. Ph. artvinensis and Ph. satunini differ in several taxonomic characters but the males have virtually identical calling songs. From a character evolution perspective, although geographically more distant, Ph. satunini is more closely related to Ph. uvarovi than Ph. artvinensis. Morphological similarities in several characters indicate Phonochorion to be most closely related to Polysarcus zacharovi and the Poecilimon heroicus-group. Within the genus Phonochorion, song structure and morphological characters clearly indicate Ph. uvarovi to be the basal taxon.

Weather factors affecting the male mate-locating tactics of the small copper butterfly (Lepidoptera: Lycaenidae)

Jun-Ya IDE

Eur. J. Entomol. 107 (3): 369-376, 2010 | DOI: 10.14411/eje.2010.046

Males of the small copper butterfly, Lycaena phlaeas daimio, exhibit two mate-locating tactics: patrolling and perching. Field investigations were conducted to determine the biotic and abiotic factors affecting the mate-locating behaviour of male L. phlaeas. Patrolling was often observed when light intensity was high. Perching was performed throughout the day regardless of environmental conditions, but the chasing of passing insects increased at high light intensities. The activity patterns of the males were not affected by those of the females. The thoracic temperatures of patrolling males were lower than those of perching males under cool conditions, suggesting that patrolling males lose heat more easily. In contrast, perching males may more easily regulate their body temperature to a suitable level as they fly for shorter periods and can bask while waiting for mates. These results highlight several reasons (i.e., heat loss, energetic costs) why males patrol when weather conditions are favourable.

Selective oviposition in fertilized seed of Ilex integra by the wasp Macrodasyceras hirsutum (Hymenoptera: Torymidae)

Etsuro TAKAGI, Kazunobu IGUCHI, Masanori SUZUKI, Katsumi TOGASHI

Eur. J. Entomol. 107 (2): 197-202, 2010 | DOI: 10.14411/eje.2010.026

It is speculated that the wasps that attack the seeds of gymnosperm trees (conifers) before they are fertilized can induce unfertilized seeds to accumulate storage material whereas those that attack after the seeds are fertilized selectively oviposit in fertilized seeds. Moreover, in the case of the wasps that oviposit after fertilization of seed, the presence of unfertilized seeds and seedless fruit may increase plant fitness via reduced parasitism of the viable seed. To determine the relationship between the two strategies, host manipulation or selective oviposition, and the time of fertilization of the seeds of angiosperm host plants, fertilized seed of Ilex integra Thunb. was dissected out of berries either immediately after the flight of the seed wasp Macrodasyceras hirsutum Kamijo in the field or the death of adults in the laboratory. The wasps oviposited mostly in fertilized seeds and rarely in unfertilized seeds. Unfertilized seeds, produced by flowers enclosed in pollen exclusion bags, and then exposed to wasps did not contain immature wasps or storage material, which indicates that the wasp did not oviposit in unfertilized seeds. These results support the above mentioned hypothesis and indicate that the substantial proportion of seedless berries do not function as an egg sink.

Isolation of nine polymorphic microsatellite loci from the leaf beetle, Lema (Lema) coronata (Coleoptera: Chrysomelidae: Criocerinae)

Yoko MATSUMURA, Izumi YAO

Eur. J. Entomol. 108 (4): 697-699, 2011 | DOI: 10.14411/eje.2011.088

Sexual selection is thought to result in an elongation of genitalia in insects. Part of the genitalia of the leaf beetle Lema (Lema) coronata Baly is approximately twice the body length in both sexes. Nine microsatellite loci were isolated from L. (L.) coronata for use in future studies on the correlation between genital length and reproductive success. The nine loci were polymorphic, with three to six alleles per locus recorded in 40 individuals. Observed heterozygosity ranged from 0.08 to 0.38 and expected heterozygosity from 0.51 to 0.75. The non-exclusive probability of the second parent and the identity calculated from the set of loci were 0.011 and < 0.001, respectively. A deviation from the Hardy-Weinberg equilibrium was detected at all nine loci, i.e. significant heterozygote deficiencies, and several hypotheses accounting for this are discussed. The isolated loci carried independent information. Five polymorphic loci were amplified in a related sympatric species, L. (L.) scutellaris, which has relatively short genitalia. These microsatellite makers will be used to determine the paternity of offspring of females multiply mated in the laboratory and compare the selection pressures operating on genital length in these closely related species.

Short term response of ants to the removal of ground cover in organic olive orchards

Mercedes CAMPOS, Luisa FERNÁNDEZ, Francisca RUANO, Belén COTES, Manuel CÁRDENAS, Juan CASTRO

Eur. J. Entomol. 108 (3): 417-423, 2011

Ants are the most abundant group of soil arthropods in olive groves where they are involved in various trophic relationships of great importance for crops. The system of soil management is one agricultural practice that has a great effect on ants, so the objective of this study was to compare ant populations in organic olive orchards with a ground cover of natural vegetation and others where this natural vegetation is mechanically removed at the beginning of June. Ants were sampled using pitfall traps at 14, 30, 70 and 90 days after the removal of the ground vegetation. Overall, ant biodiversity did not change. However, changes were observed in the abundance of ant species, in particular, in those species that build shallow nests in the soil, both between the rows of trees and under the canopy of olive trees. In contrast, deep nesting species, such as Messor barbarus, were not affected. The response also differed between the various genera: the abundance of Cataglyphis increased, due to there being more of the species C. rosenhaueri, while there was a significant fall in Aphaenogaster, due to the decline in abundance of A. senilis. Thirty days after the removal of vegetation, the response of most of the genera was clearly noticeable, due to the increased activity of workers, and in some cases there were still differences after 90 days.

Highly polymorphic di- and trinucleotide microsatellite markers for the grapevine yellows disease vector Hyalesthes obsoletus (Auchenorrhyncha: Cixiidae)

Miriam IMO, Julia LÜNEBURG, Thomas HANKELN, Alfred SEITZ, Jes JOHANNESEN

Eur. J. Entomol. 108 (1): 161-163, 2011 | DOI: 10.14411/eje.2011.019

Seven polymorphic microsatellite loci were developed for the planthopper Hyalesthes obsoletus, vector of stolbur 16SrXII-A phytoplasma. The loci have di- or trinucleotide repeat motifs and are highly variable with 10 to 22 alleles per locus. Observed heterozygosity ranged from 0.278 to 0.950 for the 78 individuals genotyped. One locus is sex-linked. No linkage between loci was found. All loci amplified consistently among phylogeographic as well as host-plant related samples and proved highly informative for population genetic studies.

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