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Performance of a predatory ladybird beetle, Anegleis cardoni (Coleoptera: Coccinellidae) on three aphid speciesOMKAR, Gyanendra KUMAR, Jyotsna SAHUEur. J. Entomol. 106 (4): 565-572, 2009 | DOI: 10.14411/eje.2009.071 Qualitative and quantitative differences in prey are known to affect the life histories of predators. A laboratory study was used to evaluate the suitability of three aphid prey, Aphis gossypii, Aphis craccivora and Lipaphis erysimi, for the ladybird beetle, Anegleis cardoni (Weise). Development was fastest on A. gossypii followed by A. craccivora and L. erysimi. Percentage pupation, immature survival, adult weight and the growth index were all highest when reared on A. gossypii and lowest on L. erysimi. Similarly, oviposition period, lifetime fecundity and egg viability were all highest on a diet of A. gossypii, lowest on L. erysimi and intermediate on A. craccivora. Age-specific fecundity functions were parabolic. Adult longevity, reproductive rate and intrinsic rate of increase were all highest on A. gossypii and lowest on L. erysimi. Life table parameters reflected the good performance on A. gossypii and poor performance on L. erysimi. Estimates of individual fitness values for the adults reared on A. gossypii and A. craccivora were similar and higher than that of adults reared on L. erysimi. Thus, the three species of aphid can all be considered essential prey for A. cardoni. |
Chemical cues mediating aphid location by natural enemiesEduardo HATANO, Grit KUNERT, J.P. MICHAUD, Wolfgang W. WEISSEREur. J. Entomol. 105 (5): 797-806, 2008 | DOI: 10.14411/eje.2008.106 There is increasing evidence that chemical cues play a pivotal role in host selection by the natural enemies of aphids. We use Vinson's (1976) division of the host selection process into habitat location, host location and host acceptance for both parasitoids and predators and review what is known about the role of semiochemicals in aphid selection by natural enemies. For habitat location (i.e. detection of the host plant), volatiles emitted by plants after aphid attack have been described for a number of plant-aphid interactions. These synomones indicate not only the presence of an aphid host plant to the predator or parasitoid, but also the presence of aphids. Volatiles emitted from undamaged host plants are often attractive to aphid parasitoids, but less so for predators. Host location by the natural enemy on the food plant is guided by semiochemicals that mostly originate from the aphids, in particular aphid alarm pheromone, honeydew, or the smell of the aphid itself. Host acceptance is guided by contact chemicals for both predators and parasitoids. In parasitoids, host recognition may be based on visual cues or on contact chemicals on the aphid's cuticle, whereas host acceptance is ultimately based on as yet unknown substances within the aphid's hemolymph. While it appears that many predators and parasitoids are attracted to the same semiochemicals, synergistic and antagonistic interactions among chemical substances have only rarely been investigated. More research into model systems is needed, not only to identify important semiochemicals, but also to determine their range of attraction. Recent progress in the development of analytical techniques has created new opportunities to improve our understanding of the chemical ecology of aphid-natural enemy interactions in the coming years. |
Chilocorus renipustulatus (Coleoptera: Coccinellidae) dominates predatory ladybird assemblages on Sorbus aucuparia (Rosales: Rosaceae)Emanuel KULA, Oldøich NEDVÌDEur. J. Entomol. 108 (4): 603-608, 2011 | DOI: 10.14411/eje.2011.078 Fourteen predatory species of ladybirds (Coleoptera: Coccinellidae) were collected from May to October 2008 from mountain ash (Sorbus aucuparia) infested with the scale insect Chionaspis salicis at 31 localities in the Ore Mountains, northern Bohemia, Czech Republic. Chilocorus renipustulatus, usually a rare species, made up 85% of the individuals collected (1690). Other abundant species were Coccinella septempunctata, Calvia quatuordecimguttata, Adalia bipunctata and Adalia decempunctata. The invasive alien Harmonia axyridis was present but made up less than one per cent of the individuals collected. Niche overlap between pairs of ladybird species measured in terms of the coefficient of community, Morisita's index and cluster analysis showed that microhabitat preferences were similar and hence the possibility of competition was high in two pairs of congeneric species (Chilocorus and Calvia). Larvae of Ch. renipustulatus were abundant from mid-June through August and were still present in October. |
The occurrence of summer diapause in the large white butterfly Pieris brassicae (Lepidoptera: Pieridae): A geographical perspectiveHubert R. SPIETH, Ulrich PÖRSCHMANN, Carola TEIWESEur. J. Entomol. 108 (3): 377-384, 2011 At the south western border of its extensive distribution, the multivoltine large white butterfly, Pieris brassicae L., is exceptional in undergoing summer diapause or aestivation. In all other regions investigated, P. brassicae pupae only hibernate. The transitional zone from non-aestivating to aestivating populations is a geographically stable region south of the Pyrenees. The restriction of this response to this region cannot be accounted for in terms of genetics as aestivation is intermediately inherited, with the heritability (h2) of aestivation in inbreeding lines between 0.35 and 0.77. Two hypotheses are presented to explain why this species does not aestivate in more northern regions. First, aestivation is a behaviour that serves to synchronize generations in areas where this species produces a high number of generations per year. Second, aestivation reduces the incidence of parasitism suffered by the butterfly by desynchronizing its life cycle from that of its main parasitoid, Cotesia glomerata. The two hypotheses are not mutually exclusive and both seem to be adaptive where the species is multivoltine. |
Morphological diversity of male salivary glands in Panorpidae (Mecoptera)Na MA, Shu-Yu LIU, Bao-Zhen HUAEur. J. Entomol. 108 (3): 493-499, 2011 The morphology of the male salivary glands of eighteen species of Panorpidae from China was studied using light microscopy. The results show that the male salivary glands differ markedly both at generic and specific levels. In Neopanorpa, the salivary glands consist of only two simple long secretory tubes extending to the fifth or sixth abdominal segment, whereas in Sinopanorpa, the salivary glands are composed of six extremely elongated secretory tubes. In Panorpa, the salivary glands are quite diverse, comprising two simple short secretory tubes only extending to the prothorax in the P. amurensis group (P. liui and P. jilinensis), six long tubes in the P. centralis group, eight to twelve in the P. diceras group and of a very variable number in the P. davidi group (especially in P. bifasciata and P. subambra). Morphology of the male salivary glands should be included in future studies on the systematics and phylogeny of the Panorpidae. |
Cream and albinotic - two new mutations affecting body colour in Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)Radomír SOCHAEur. J. Entomol. 108 (1): 17-24, 2011 | DOI: 10.14411/eje.2011.002 Two new body-colour mutations, albinotic (alb) and cream (cr) are isolated and described for the flightless wing-polymorphic bug, Pyrrhocoris apterus (L.). The body colour of alb mutants is white and that of cr mutants either a light cream or creamy yellow. Both the alb and cr mutations most probably inhibit the biosynthesis of the red pigment in epidermal cells that is responsible for the red-coloured body of wild-type bugs. Although sometimes the body colour of younger larval instars of cr mutants is a slightly darker creamy yellow and that of last larval instars of the alb mutants a slightly whiter greyish, there were no other important developmental changes in the body colour of alb and cr homozygous bugs associated with metamorphosis and post-metamorphic aging of adults. Standard genetic analyses showed that both these mutations are inherited as autosomal recessives and exhibit complete penetrance and uniform expression in both sexes. The fertility of the alb and cr homozygous females and fertilization success of the alb and cr homozygous males were substantially lower than those of wild-type bugs. |
Genetic diversity, population structure and taxonomy of Calopteryx splendens (Odonata: Calopterygidae): An AFLP analysisSaber SADEGHI, Tina KYNDT, Henri J. DUMONTEur. 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. |
Physiology of heartbeat reversal in adult Drosophila melanogaster (Diptera: Drosophilidae)Karel SLÁMAEur. J. Entomol. 107 (1): 13-31, 2010 | DOI: 10.14411/eje.2010.002 Heartbeat patterns were monitored in the living bodies of decapitated adult flies using several electrocardiographic methods (pulse-light optocardiography, thermocardiography, strain-gauge cardiography). Unlike other insect species, in which there is a peristaltic segmental propagation of cardiac contractions, Drosophila uses extremely efficient synchronic cardiac contractions. The rate of synchronic cardiac pulsation, which is characterized by simultaneous propagation of anterograde systolic contractions along all the segments of the heart, is relatively fast (~ 4 Hz at room temperature). This pulsation is used mainly for the vigorous pumping of haemolymph into the head and thorax through a narrow elastic tube, the aorta (anterograde I heartbeat). In addition, this synchronic pulsation is also used to enhance the circulation of haemolymph throughout the abdominal body cavity (anterograde II heartbeat). The switch between thoracic (anterograde I) and abdominal (anterograde II) haemolymph circulation is regulated by periodically alternating, tetanic contractions and relaxations of the conical heart chamber (ventricle). In the latter there is a pair of slit-like apertures, which are closed or opened by contraction or relaxation of the organ, respectively. During contraction of the conical chamber, the apertures are tightly constricted for several seconds and haemolymph is pumped forwards into the aorta (anterograde I heartbeat). Conversely, during relaxation of the conical chamber, the apertures are wide open for a few seconds, haemolymph leaves the heart and leaks out through open apertures and circulates from the tail to the base of the abdomen. The backward oriented, retrograde heartbeat recorded in other insects, has a lower frequency (1 to 2 Hz), occurs in Drosophila only sporadically and usually in the form of individual or twinned systolic peaks of large amplitude. Unlike the synchronic nature of the anterograde I and II cardiac contractions, propagation of the relatively slow retrograde heartbeat is by peristalsis. The newly discovered, compact ventricle with atrium and synchronic functioning of the insect heart shows structural and functional analogies with the functioning of the human heart. |
Molecular phylogenetic analysis of a scale insect (Drosicha mangiferae; Hemiptera: Monophlebidae) infesting mango orchards in PakistanMuhammad ASHFAQ, Jehan ARA, Ali Raza NOOR, Paul D.N. HEBERT, Shahid MANSOOREur. J. Entomol. 108 (4): 553-559, 2011 | DOI: 10.14411/eje.2011.071 Mango orchards in Pakistan are attacked by the scale insect, Drosicha mangiferae (Hemiptera: Monophlebidae), commonly called the "mango mealybug". This insect is univoltine, active from December through May and targets multiple host plants. We used DNA nucleotide sequences to characterize and determine the phylogenetic status of D. mangiferae. Mango mealybugs were collected from several tree species from different localities and patterns of phylogenetic and genetic diversity were examined at both nuclear (18S, ITS1) and mitochondrial (COI) genes. Phylogenetic analysis confirms that the mango mealybug belongs to the family Monophlebidae. Minor genetic differences in both the ITS1 and the COI barcode region were noted among D. mangiferae collected from different geographic localities. These genetic differences revealed the existence of two genotypes of D. mangiferae that are region specific but not host-specific. |
Contribution to the biochemical characterization of the silk and structure characterization of the cocoons of the horse chestnut leaf miner Cameraria ohridella (Lepidoptera: Gracillariidae)Veronika HNÌVSOVÁ, Dalibor KODRÍK, Franti¹ek WEYDAEur. J. Entomol. 108 (4): 711-715, 2011 | DOI: 10.14411/eje.2011.091 This study of the proteins in the silk of the summer and winter cocoons of the horse chestnut leaf miner Cameraria ohridella revealed they can inhibit protease activity. The inhibitory activity of the summer silk was higher against both the fungal proteinase K and bacterial subtilisin than that of the winter silk. Also, the winter silk was more effective in inhibiting proteinase K than subtilisin. Further, it was demonstrated that some of the silk proteins are glycosylated probably by mannose carbohydrates. An electron microscopy study of the cocoons revealed the presence of silk fibres with different diameters in some pupal chambers. |
Seasonal constraints on the mandible allometry of Lucanus cervus (Coleoptera: Lucanidae)Sönke HARDERSEN, Anna L.M. MACAGNO, Roberto SACCHI, Ilaria TONIEur. J. Entomol. 108 (3): 461-468, 2011 In insects, allometries of exaggerated traits such as horns or mandibles are often considered species specific and constant during a season. However, given that constraints imposed by the advancing season affect the developmental processes of organisms, these allometries may not be fixed, and the switch point between morphs may vary between populations and within populations during a season. The hypothesis of such a seasonal variation in exaggerated traits was tested using the dimorphic males of the beetle Lucanus cervus. The remains of specimens killed by predators were collected along forest tracks from mid May to late August 2008 in a protected lowland forest in northern Italy. The largest beetles were collected in mid May and average size thereafter decreased. Males collected early in the season mostly had large mandibles (i.e. they belonged to the major morph). In contrast, late in the season the probability of finding males with large mandibles was very low. The threshold body size determining morph expression also shifted during the season. Early in the season, the threshold pronotum width for a 50% chance of developing into the major morph was 1.74 cm, whereas later in the season it was 1.90 cm. This shift in the threshold body size was interpreted as the effect of phenotypic plasticity in a population exposed to constraints imposed by the advancing season. |
Phylogenetic relationships of selected European Ennominae (Lepidoptera: Geometridae)Erki ÕUNAP, Juhan JAVOI©, Jaan VIIDALEPP, Toomas TAMMARUEur. 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. |
Homologies of the head of Membracoidea based on nymphal morphology with notes on other groups of Auchenorrhyncha (Hemiptera)Dmitry A. DMITRIEVEur. J. Entomol. 107 (4): 597-613, 2010 | DOI: 10.14411/eje.2010.069 The ground plan and comparative morphology of the nymphal head of Membracoidea are presented with particular emphasis on the position of the clypeus, frons, epistomal suture, and ecdysial line. Differences in interpretation of the head structures in Auchenorrhyncha are discussed. Membracoidea head may vary more extensively than heads in any other group of insects. It is often modified by the development of an anterior carina, which apparently was gained and lost multiple times within Membracoidea. The main modifications of the head of Membracoidea and comparison of those changes with the head of other superfamilies of Auchenorrhyncha are described. |
Descriptions of larvae of Megadytes (Coleoptera: Dytiscidae: Dytiscinae): The subgenera Trifurcitus and Megadytes s. str., ground plan of chaetotaxy of the genus and phylogenetic analysisMariano C. MICHATEur. J. Entomol. 107 (3): 377-392, 2010 | DOI: 10.14411/eje.2010.047 The three larval instars of Megadytes (M.) carcharias Griffini and M. (Trifurcitus) fallax (Aubé) are described and illustrated in detail for the first time, with an emphasis on morphometry and chaetotaxy of the cephalic capsule, head appendages, legs, last abdominal segment and urogomphi. The ground plan of chaetotaxy of the genus Megadytes Sharp is described and illustrated based on three of the four recognised subgenera. First-instar larvae of Megadytes are characterised by the presence of a large number of additional sensilla on almost every part of the body. Primary chaetotaxy of the subgenera (Bifurcitus Brinck based on third instar) is very similar, with few differences including (1) shape of the setae on the anterior margin of the frontoclypeus; (2) presence or absence of a ring of multi-branched setae on distal third of mandible; and (3) number of setae on the urogomphus. A cladistic analysis of Dytiscidae, based on 169 larval characters and 34 taxa, indicates that: (1) Trifurcitus Brinck deserves generic status; (2) Cybistrini are not closely related to Hydroporinae; (3) the absence of a galea in Cybistrini is a secondary loss independent of that in Hydroporinae; (4) Cybistrini are well supported by many characters (including several aspects of first-instar chaetotaxy). |
Altitudinal distribution of moths (Lepidoptera) in Mt. Jirisan National Park, South KoreaSei-Woong CHOI, Jeong-Seop ANEur. J. Entomol. 107 (2): 229-245, 2010 | DOI: 10.14411/eje.2010.031 The relationship between species richness of plants and animals and altitude can be either hump-shaped, a monotonic decrease or increase. In this study the altitudinal distribution of moths on one of the highest mountains in South Korea was investigated. Moths were captured using a UV-light trap from May to October in 2007 and 2008. This revealed that the relationship between the total numbers of moth species and individuals and altitude is hump-shaped. A significant relationship was also recorded between the size of the area at each altitude and moth abundance and richness. However, the evenness index yielded a consistent decrease with increase in altitude because of the dominance of few species at high altitudes. Non-metric multidimensional scaling identified two major axes for the moth assemblage on Mount Jirisan. The correlations between the axes and variables demonstrated that the first axis was strongly correlated with altitude and aspect and the second axis with forest and site location. |
Comparative analysis of the location of rDNA in the Palaearctic bushcricket genus Isophya (Orthoptera: Tettigoniidae: Phaneropterinae)Beata GRZYWACZ, Anna MARYAÑSKA-NADACHOWSKA, Dragan P. CHOBANOV, Tatjana KARAMYSHEVA, El¿bieta WARCHA£OWSKA-¦LIWAEur. J. Entomol. 108 (4): 509-517, 2011 | DOI: 10.14411/eje.2011.066 The present study focused on the evolution of the karyotype in 21 taxa of the genus Isophya, which was done by mapping the location on the chromosomes of ribosomal RNA (rRNA) coding genes using fluorescence in situ hybridization (FISH) with an 18S rDNA probe and using silver staining (AgNO3) to evaluate the activity of major rDNA clusters. Since the chromosome number and sex determination do not vary in this genus, the above markers were used in a detailed comparison of the cytogenetic features of species of Isophya. The species analyzed were placed into three groups based on the location of rDNA on their chromosomes: (1) rDNA-FISH signals only on the two long pairs of autosomes, (2) rDNA-FISH signals on one long and one short pair of autosomes, and (3) rDNA-FISH signals on three to five different sized pairs of autosomes. These groupings partly correspond to the morphological groupings proposed in earlier studies. One long pair of autosomes frequently carried rDNA in all the Isophya species and probably is a plesiomorphic character for these taxa. The cytogenetic mapping revealed great variability among Isophya species in the chromosomal location of major rDNA clusters. Our results suggest that the observed variation in the number of rDNA clusters can be an important species-group specific phylogenetic marker. Analysis of 18S rDNA hybridization signals showed that the evolutionary dynamics of rDNA in this genus is remarkably high and accompanied by changes in the structure of chromosomes bearing rDNA at an inter- and intra-specific level. The telomeric sequence (TTAGG)n hybridized with the termini of most of chromosomes, however, some chromosome ends lacked signals probably due to a low copy number of telomeric repeats. |
Does the decline of red wood ants after clear-cutting favour epigeic arthropods?Michal ZMIHORSKIEur. J. Entomol. 108 (3): 425-430, 2011 In forest ecosystems in the temperate and boreal zones in Europe, red wood ants (RWA, Formica rufa group) have a significant affect as predators and competitors in communities of ground-dwelling arthropods. Therefore, the spatiotemporal distribution and abundance of RWA affect the distribution of many other species. The hypothesis that a reduction in the abundance of RWA in clear-cut areas enables other arthropods to increase in abundance was tested. The study was conducted in NW Poland in 2007 and 2008. A total of 276 1×1 m plots were sampled and 1,696 individuals recorded. The probability of the occurrence of RWA decreased significantly towards the center of clear-cut areas and increased with increasing plant cover. The frequency of Lasius platythorax, Formica fusca and spiders in the plots significantly increased towards the edge of a clear-cut area. Moreover, the occurrence of L. platythorax was negatively associated with the presence of RWA, while that of the Myrmica species was positively associated. The effect of the distance to the edge of a clear-cut area seems to be much more pronounced than the effect of RWA. This suggests that the arthropods studied prefer habitats close to the edge that are utilized by RWA than RWA-free sites located in the centre of clear-cut areas. |
Carabid beetle assemblages associated with urban golf courses in the greater Helsinki areaJarmo SAARIKIVI, Laura IDSTRÖM, Stephen VENN, Jari NIEMELÄ, D. Johan KOTZEEur. J. Entomol. 107 (4): 553-561, 2010 | DOI: 10.14411/eje.2010.064 Golf is a popular sport, with increasingly large areas of urban and peri-urban land being designated for golf course development. Yet, more than half of the land area of a typical golf course is considered rough and out-of-play areas that can, if managed appropriately, provide habitats for wildlife. Using pitfall traps, 6944 carabid beetles belonging to 72 species were collected from five urban golf courses and three areas designated for golf course development around the city of Helsinki, Finland in 2007. The courses were rich in carabid species and distinct in their species assemblages. Golf courses were dominated by habitat generalists, species capable of flight and medium to large-sized species. The three courses with areas designated for further golf course development showed that the assemblages of beetles associated with these golf courses have retained many elements from the pre-existing habitats. The oldest golf course is characterised by a more evenly distributed and diverse carabid beetle assemblage, probably due to its higher habitat heterogeneity and longer successional development. However, even this golf course is dominated by generalist species, implying that golf courses may not provide suitable habitats for specialists. It is assumed that the high species richness of golf courses is attributed to the high habitat diversity of these environments, ranging from the strongly human-modified to more natural patches, which provide habitats for many generalist and open-habitat species. Golf courses may, however, with the appropriate management of out-of-play areas provide an opportunity for conserving biodiversity. |
Landscape structure affects activity density, body size and fecundity of Pardosa wolf spiders (Araneae: Lycosidae) in winter oilseed rapeThomas DRAPELA, Thomas FRANK, Xaver HEER, Dietmar MOSER, Johann G. ZALLEREur. J. Entomol. 108 (4): 609-614, 2011 | DOI: 10.14411/eje.2011.079 In large parts of Europe Pardosa spp. (Lycosidae) are among the most abundant wolf spiders in arable fields and potentially important natural control agents of pests. We studied the influence of landscape factors on activity density, adult body size and fecundity of P. agrestis in 29 winter oilseed rape fields (Brassica napus L.) in Eastern Austria using pitfall traps. Landscape data were obtained for eight circular landscape sections around each field (radii 250-2000 m). Multivariate regression models were used to analyze the data. Activity density was highest when the length of strips of grassy road-sides in the surroundings was highest and distance to the next grassy fallow lowest. Body size was negatively related to activity density and to the length of road-side strips and positively to woody areas in the vicinity of the fields. Clutch size was unrelated to any of the landscape factors tested but was positively correlated with female body size. Woody areas and grassy fallow in the close vicinity of the fields had a positive influence on number of offspring per female and total number of offspring. These results indicate that various non-crop components in the landscape surrounding oilseed rape fields can specifically influence the activity density and fitness-related traits of P. agrestis in crops. The possible role of Pardosa spp. in natural pest control is discussed. |
Functional responses of immature stages of Propylea quatuordecimpunctata (Coleoptera: Coccinellidae) to Aphis fabae (Hemiptera: Aphididae)Nickolaos E. PAPANIKOLAOU, Angeliki F. MARTINOU, Dimitrios C. KONTODIMAS, Yiannis G. MATSINOS, Panagiotis G. MILONASEur. J. Entomol. 108 (3): 391-395, 2011 Functional responses of immature stages of Propylea quatuordecimpunctata (L.) to varying densities of Aphis fabae Scopoli reared on Vicia faba L. were evaluated under laboratory conditions. All larval stages of the predator were starved for 12 h prior to being placed individually for 24 h in plastic containers with different densities of its prey, A. fabae, on potted V. faba plants. Logistic regression analysis of the proportion of aphids consumed as a function of initial density indicated that all larval instars of P. quatuordecimpunctata exhibited a type II functional response when searching for A. fabae on V. faba plants. Attack rates (0.059, 0.057, 0.065 and 0.064) and handling times (6.18, 2.37, 1.06 and 0.44) for first to fourth instar larvae, respectively, were estimated using Holling's disc equation. |
Recombinant expression, purification and characterization of Bombyx mori (Lepidoptera: Bombycidae) pyridoxal kinaseShuo-Hao HUANG, Wang MA, Ping-Ping ZHANG, Jian-Yun ZHANG, Yan-Feng XIE, Long-Quan HUANGEur. J. Entomol. 108 (1): 25-34, 2011 | DOI: 10.14411/eje.2011.003 Pyridoxal kinase (PLK; EC 2.7.1.35) is a key enzyme in the metabolism of vitamin B6 (VB6) in Bombyx mori. A fusion expressional vector pET-22b-BPLK-His was constructed using a sub-cloning technique, the recombinant B. mori PLK was then expressed in Escherichia coli, purified and characterized. Bioinformatics were used to deduce the protein structure and genomic organization of this enzyme. Using Ni Sepharose affinity column chromatography, the recombinant protein was purified to very high degree (approximately 90%). The recombinant PLK exhibits a high specific enzymatic activity (1800 nmol/min/mg of protein). The maximum catalytic activity of this enzyme was recorded over a narrow pH range (5.5-6.0) and Zn2+ is the most effective cation for catalysis under saturating substrate concentrations. When only triethanolamine is present as the cation, K+ is an activator of PLK. A double reciprocal plot of initial velocity suggests that the enzyme catalyses the reaction by means of a sequential catalytic mechanism. Under optimal conditions, the Km value for the substrates of ATP and pyridoxal are 57.9 ± 5.1 and 44.1 ± 3.9 µM. B. mori's genome contains a single copy of the PLK gene, which is 7.73 kb long and contains five exons and four introns, and is located on the eighth chromosome. The PLK may be a dimer with two identical subunits under native conditions, and it is hypothesized that each monomer contains eight α-helices (α1-8), nine β-strands (β1-9) and two segments of 310 helices. |
Analysis of the lipids mobilized by adipokinetic hormones in the firebug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)Iva BÁRTÙ, Ale¹ TOMÈALA, Radomír SOCHA, Petr ©IMEK, Dalibor KODRÍKEur. J. Entomol. 107 (4): 509-520, 2010 | DOI: 10.14411/eje.2010.058 Effects of two adipokinetic hormones (Pyrap-AKH and Peram-CAH-II) on the presence of diacylglycerol (DG) molecular species and their fatty acid (FA) constituents in the haemolymph of the firebug Pyrrhocoris apterus were investigated using liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MS). The results show that DGs with characteristic FAs are preferentially mobilized from the fat body (FB) by the action of both the AKHs produced by P. apterus. Both the macropterous and brachypterous morphs have similar DG and FA profiles. A difference in the action of the Pyrap-AKH and the Peram-CAH-II, however, results in distinct differences in the distribution of FAs in the macropterous morph. It seems that C16 to a slight extent and unsaturated C18 FAs mainly play a dominant role in the AKH based action, in particular linoleic acid (18:2), which represents 50-60% of the total DG mobilized. The metabolically active C16 and C18 FAs are preferentially absorbed from the linden seeds and accumulated in the FB. The relationships between AKH action and FA distribution in DGs in P. apterus, compared to other insect species are summarized and discussed in detail. |
Temperature-dependent development of dubas bug, Ommatissus lybicus (Hemiptera: Tropiduchidae), an endemic pest of date palm, Phoenix dactyliferaAbdul Monim MOKHTAR, Salem Saif Al NABHANIEur. J. Entomol. 107 (4): 681-685, 2010 | DOI: 10.14411/eje.2010.076 Dubas bug, Ommatissus lybicus Bergevin, is an important pest of date palm on the Arab peninsula. This sucking insect causes great damage to the trees and reduces the quantity and quality of the dates. Effect of temperature on the development of the immature stages of O. lybicus was studied in the laboratory by rearing them at nine constant temperatures, ranging from 15 to 35°C. Development was successfully completed at temperatures ranging from 20 to 35°C for eggs and from 20 to 32.5°C for nymphs. The lower thermal thresholds for development of eggs, nymphs and egg-adult were estimated by means of linear regression as 12.9, 12.9 and 13.2°C, respectively. Thermal units required for the development of the same stages were 572.5, 648.2 and 1184.4 degree-days, respectively. The lethal high temperatures were also estimated using a nonlinear model as 34.5, 43.4 and 34.6°C for eggs, nymphs and total immature stages, respectively. The development rate and survival data indicate that the optimum temperature range for O. lybicus is 25-27.5°C. |
Cooperative defence of brood in Nicrophorus quadripunctatus (Coleoptera: Silphidae)Seizi SUZUKIEur. J. Entomol. 108 (4): 561-563, 2011 | DOI: 10.14411/eje.2011.072 A positive correlation between the parental effort of a male and female should promote stable biparental care. In order to prevent infanticide male and female burying beetles are said to guard against intruders cooperatively and the presence of a male partner is said to increase the probability of successful defence. However, this hypothesis is supported only by indirect evidence. In this study this hypothesis is tested by direct observation. Whether the intruder was male or female, contests between the same and the opposite sex occurred, although there were few contests between resident females and intruding males. In addition, resident pairs tended to win irrespective of the sex of the intruder, although it is reported that among burying beetles large beetles usually win intra-sexual contests. In the presence of a partner, a small resident can defend a carcass against a large con-sexual intruder. These results suggest that by means of biparental cooperation burying beetles can repel stronger intruders and supports the hypothesis that the threat of infanticide is the primary explanation for extended biparental care in these beetles. |
Detection of a single nucleotide polymorphism (SNP) DNA marker linked to cocoon traits in the mulberry silkworm, Bombyx mori (Lepidoptera: Bombycidae)Sivaramakurup SREEKUMAR, Southekal K. ASHWATH, Monika SLATHIA, Sundaramurthy N. KUMAR, Syed M.H. QADRIEur. J. Entomol. 108 (3): 347-354, 2011 Cocoon weight and shell weight are the key economic traits ultimately determining silk yield. In order to detect the main quantitative trait loci (QTL) associated with the cocoon traits of the mulberry silkworm, Bombyx mori, the parents of larvae that produced cocoons that differed greatly in weight and shell weight were screened using 240 primer pairs of single nucleotide polymorphic markers (SNPs) representing all the 28 linkage groups in silkworm. Out of the 240 primer pairs, 48 (20%) revealed distinct polymorphism between the parents, which was confirmed by the co-dominant expression of both polymorphic PCR products in the F1 generation. The bulked segregant analysis (BSA) was used to compare the SNP profiles of the parents, F1 and F2 bulks using the 48 informative SNP primers. This revealed that out of 48 primer pairs, only one pair, i.e., No. 04124 of the linkage group 4 showed clear differences in the amplified products between the bulks corresponding to that of the parents with different cocoon traits suggesting that the DNA regions amplified by this primer pair are closely linked to the QTL controlling the cocoon traits. The results were also confirmed by screening the backcross (BC) progeny. This is the first report of the identification of a QTL using SNPs with BSA. The results of the present study indicate that it might be possible to use SNPs for marker assisted selection (MAS) in silkworm breeding programs aimed at improving cocoon traits. |
Phylogeny and nomenclature of the box tree moth, Cydalima perspectalis (Walker, 1859) comb. n., which was recently introduced into Europe (Lepidoptera: Pyraloidea: Crambidae: Spilomelinae)Richard MALLY, Matthias NUSSEur. J. Entomol. 107 (3): 393-400, 2010 | DOI: 10.14411/eje.2010.048 The box tree moth, Cydalima perspectalis (Walker, 1859) comb. n., is native to India, China, Korea, Japan and the Russian Far East. Its larvae are a serious pest of different species of Buxus. Recently, C. perspectalis was introduced into Europe and first recorded from Germany in 2006. This species has been placed in various spilomeline genera including Palpita Hübner, 1808, Diaphania Hübner, 1818, Glyphodes Guenée, 1854 and the monotypic Neoglyphodes Streltzov, 2008. In order to solve this nomenclatural confusion and to find a reasonable and verifiable generic placement for the box tree moth, the morphology of the above mentioned and some additional spilomeline taxa was investigated and their phylogeny analysed. The results show that C. perspectalis belongs to a monophylum that includes three of the genera in which it was previously placed: Glyphodes, Diaphania and Palpita. Within this monophylum, it is closely related to the Asian Cydalima Lederer, 1863. As a result of this analysis, Sisyrophora Lederer, 1863 syn. rev. and Neoglyphodes Streltzov, 2008 syn. n. are synonymised with Cydalima Lederer, 1863, and five species are transferred to this genus: Cydalima capriniodes (Hampson, 1912) (Glyphodes) comb. n., Cydalima decipiens (Hampson, 1912) (Glyphodes) comb. n., Cydalima joiceyi (Janse, 1924) (Margaronia) comb. n., Cydalima perspectalis (Walker, 1859) (Phakellura) comb. n. and Cydalima pfeifferae (Lederer, 1863) (Sisyrophora) comb. rev. |
The genetic structure of phenologically differentiated Large Blue (Maculinea arion) populations (Lepidoptera: Lycaenidae) in the Carpathian BasinJudit BERECZKI, János P. TÓTH, Andrea TÓTH, Edit BÁTORI, Katalin PECSENYE, Zoltán VARGAEur. J. Entomol. 108 (4): 519-527, 2011 | DOI: 10.14411/eje.2011.067 The infraspecific taxonomy of the European populations of the Large Blue (Maculinea arion) is confusing. Several subspecies have been described mostly based on external morphological features. In the Carpathian Basin two subspecies have been distinguished. Maculinea arion arion flies from mid-May to mid-June and Maculinea arion ligurica is on the wing from the end of June to mid-August. The two forms show some differentiation in habitat use, but occasionally can also share habitats with two peaks in the appearance of butterflies. Our aim was to study the level and structure of genetic variation in a set of populations of the two phenologically different M. arion. Imagos were collected from 8 localities between 2000 and 2006. Enzyme polymorphism was analysed at 13 enzyme loci using polyacrylamide gel electrophoresis. In the analysis of the data, we estimated the parameters of polymorphism. To study the pattern of genetic differentiation F-statistics, hierarchical F-statistics and AMOVA were computed. GeneClass and Structure were both applied to analyse the differentiation between the two phenologically different sets of populations. Cavalli-Sforza and Edwards' arc distances were calculated and a UPGMA dendrogram was constructed on the basis of the distance matrix. PCA analysis was also carried out using the allele frequencies of the individuals. The level of polymorphism was relatively high in M. arion. The results of all analyses indicated that the differences between the two sets of phenologically different populations accounted for a low percentage of the total differentiation. In addition, a sizeable amount of variation could be attributed to the differences among the samples collected from the same population in consecutive years. Thus, we concluded that the "spring" and "summer arion" could not be considered as separate ESUs, although we could attribute conservation value to both forms on the basis of their phenological differentiation and habitat use. |
Morphometry and number of spermatozoa in drone honeybees (Hymenoptera: Apidae) reared under different conditionsAdel M. MAZEEDEur. J. Entomol. 108 (4): 673-676, 2011 | DOI: 10.14411/eje.2011.085 The effects of three factors operating during pre-emergence development period on some characteristics of drones were studied. Weight of newly emerged drones, length of forewing, length of tibia, length of femur, length and width of basitarsus and number of spermatozoa in drones from colonies in which the workers had access to drone brood (A), the size of brood cells differed (B) or the colony had a queen or was queenless (C), were determined. For this purpose, 9 colonies were chosen at random from the test apiary and prepared so that each contained one empty Langstroth frame with six small sub-frames containing drone combs, three of which were used to test the effect of one level and the other three the other level of each factor. The results showed that, colony status had a greater effect on the parameters measured than either the size of the brood cells or whether the workers had access to sealed brood cells. Most of the parameters were significantly different in C, whereas only a few in B and non in A were significantly different. The distance between discriminant scores in each experiment enhanced the previous results, as it was highest in C, followed by B and then A. Optimal drone characteristics may be recorded for colonies in which the queens were induced to lay unfertilized eggs in newly built drone combs, and then removed and the drone brood reared in a queen less colony. |
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 butterfliesKonrad SACHANOWICZ, Agnieszka WOWER, Jaroslaw BUSZKOEur. 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. |
Environmental correlates of species richness of Sesiidae (Lepidoptera) in EuropeMarek B¡KOWSKI, Werner ULRICH, Zdenìk LA©TÙVKAEur. J. Entomol. 107 (4): 563-570, 2010 | DOI: 10.14411/eje.2010.065 Recent compilations of species richness for 54 European countries and large islands and linear spatial autocorrelation modelling were used to infer the influence of area and environmental variables on the number of species of clearwing moths (Sesiidae) in Europe. Area corrected species richness of rhizophagous Sesiidae peaked at about 40°N and decreased towards higher and lower latitudes. Most species rich was Greece (45 species), Bulgaria (37), Italy (35) and Romania (35). The area corrected species richness of xylophagous Sesiidae peaked at about 45°N with France (24) and Italy (22) being most species rich. Species richness was significantly positively correlated with area and the average yearly difference in temperature, and significantly negatively correlated with latitude. Island and mainland SAR slopes did not differ significantly, however island species richness per unit area appeared to be about 2 to 2.5 times lower than mainland species richness. |



