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Revision of the Oriental species of the genus Gnypetalia new status (Coleoptera: Staphylinidae: Aleocharinae), with a discussion of its phylogenetic relationshipsGrzegorz PA¦NIKEur. J. Entomol. 102 (4): 725-736, 2005 The subgenus Gnypetalia Cameron, 1939 is redefined and raised to the genus rank. Eleven valid species are recognised in the genus, six of which are described as new: Gnypetalia armata sp. n. (Solomon Islands), G. cuccodoroi sp. n. (Philippines: Luzon), G. insularis sp. n. (Solomon Islands), G. luzonica sp. n. (Philippines: Luzon, Palawan), G. nitida sp. n. (Indonesia: Sulawesi) and G. penrisseni sp. n. (Malaysia: Sarawak). One new synonym is established: Gnypetalia parva Cameron, 1950 = Ischnopoda (Caliusa) finitima Pace, 1998 syn. n. Five species are given in new combination: Gnypetalia indica (Cameron, 1939) comb. n (= Gnypeta (Gnypetalia) indica), Gnypetalia parva (Cameron, 1950) comb. n. [= Gnypeta (Gnypetalia) parva], Gnypetalia rougemontiana (Pace, 1986) comb. n [= Tachyusa (Caliusa) rougemontiana], Gnypetalia song (Pace, 1990) comb. n. [= Tachyusa (Caliusa) song] and Gnypetalia thoracica (Fauvel, 1879) comb. n. (= Tachyusa thoracica). Lectotype is designated for Gnypeta indica Cameron, 1939. The taxa are diagnosed, keyed and illustrated. The phylogeny of the aleocharine genus Gnypetalia is analysed using cladistic methods. The monophyly of Gnypetalia is confirmed and three major monophyletic species group are recognised. |
Nearctic Achalcinae with a first Australachalcus species of North America (Diptera: Dolichopodidae)Marc A.A. POLLETEur. J. Entomol. 102 (2): 279-288, 2005 | DOI: 10.14411/eje.2005.039 Both sexes of Achalcus bicolor sp.n., Achalcus longicercus sp.n., and Australachalcus latipennis sp.n. are described as additions to the Nearctic achalcine fauna. Diagnoses of five unnamed Achalcus species represented only by females are given. A key to Nearctic males and females including 10 unnamed species is provided. The new Achalcus records considerably extend the known distribution of the genus in North America, especially in the central and eastern states. Australachalcus latipennis sp.n. is the first known Nearctic species of this predominantly Neotropical and New Zealand genus. Achalcus bicolor sp.n. from Montana, Manitoba and Ontario clearly belongs to the Achalcus flavicollis species group. The eastern Achalcus longicercus sp.n. is not included in the latter species group due to the lack of a dorsal bristle on tibia I and the absence of a preapical anterodorsal bristle on femur III in both sexes. It features postgonites with strong hook-like apical processes possibly unique to this species. The presence and number of dorsal bristles on tibia I seem to be of both diagnostic and phylogenetic relevance. All northern achalcine species were collected between June and September, whereas some Californian species were taken in May and Australachalcus latipennis sp.n. from Arizona in October - November. |
Ecological and seasonal patterns in the diversity of a species-rich bee assemblage (Hymenoptera: Apoidea: Apiformes)Sabine OERTLI, Andreas MÜLLER, Silvia DORNEur. J. Entomol. 102 (1): 53-63, 2005 | DOI: 10.14411/eje.2005.008 Meaningful ecological studies on insect communities require sampling protocols that take into consideration temporal fluctuations in abundance and species composition. Bees with their specific requirements for nutrition and nesting are good indicators of landscape structure and overall biodiversity, provided the ecological and seasonal patterns they show are taken into consideration. The present two year study traced the ecological and seasonal patterns on 2 km2 of a southern slope in the Swiss Alps, ranging from 1150 to 1550 m above sea level. The study area consisted mainly of grassland under different regimes, mostly hay meadows and pastures. By direct netting at five monthly intervals in each year a total of 247 bee species were recorded. This comprehensive sampling scheme identified one of the most diverse bee faunas in Central and Northern Europe, consisting of a statistically estimated 280 species. Most species were rare with 14.6% represented by a single individual. Ecological analysis of the bee community showed that the primitively eusocial species were over represented among the abundant species and the parasitic species among the rarest. |
Expression of the melittin gene of Apis cerana cerana (Hymenoptera: Apidae) in insect cellsWan-Jun SHI, Jia-An CHENG, Chuan-Xi ZHANGEur. J. Entomol. 103 (4): 867-870, 2006 | DOI: 10.14411/eje.2006.118 A fragment encoding melittin cDNA from Apis cerana cerana fused with glutathione S-transferase gene was inserted into the multiple cloning site of the pBacFastHTb to construct a recombinant donor plasmid, pBacHT-GSTAccM, which was transposed to the target bacmid in E. coli (DH10) by Tn7 transposition function. Then the recombinant baculovirus Bacmid-GSTAccM was transfected into Tn-5B1-4 cells of the cabbage looper, Trichoplusia ni, mediated by lipofectin. The expressed protein of about 34 kDa was detected by Western blotting and triple antibody sandwich ELISA, indicating that the recombinant protein is the fusion protein of GSTAccM. Thin layer scanning showed that the expression level of GSTAccM was about 7% of the total cell protein. Purified and recovered recombinant melittin of A. c. cerana showed bioactivity in activating rabbit platelets to aggregate. |
Unusual complement of three AKH octapeptides in two species of grasshoppers (Caelifera)Gerd GÄDEEur. J. Entomol. 103 (2): 297-304, 2006 | DOI: 10.14411/eje.2006.038 The corpora cardiaca (CC) of the two grasshopper species Zonocerus elegans (Pyrgomorphidae) and Lamarckiana sparrmani (Pamphagidae) contain (a) substance(s) that cause(s) hyperlipaemia in the migratory locust and hypertrehalosaemia in the American cockroach. Isolation of neuropeptides belonging to the adipokinetic hormone (AKH) family was achieved by single-step reversed-phase high performance liquid chromatography of CC extracts from both species and monitoring tryptophan fluorescence. The material of both species showed three distinct fluorescence peaks with adipokinetic activity in the migratory locust. The peptides were identifid by at least two of the following methods: (1) sequencing by Edman degradation, (2) sequencing by tandem fast atom bombardment mass spectrometry, (3) mass determination by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry and (4) co-elution of the native and synthetic peptides. Both species were found to have three AKH peptides stored in the CC, but unlike in other grasshoppers, none of those peptides were decapeptides. In Z. elegans the following three octapeptides occur: Schgr-AKH-II (pELNFSTGWamide), Peram-CAH-II (pELTFTPNWamide) and Phymo-AKH-III (pEINFTPWWamide), whereas L. sparrmani contains the octapeptides Grybi-AKH (pEVNFSTGWamide), Pyrap-AKH (pELNFTPNWamide) and also Phymo-AKH-III. Conspecific bioassays show no adipokinetic and only a weak (not significant) hypertrehalosaemic effect (in the pamphagid grasshopper). Some explanations are offered on the possible role of these peptides in the species investigated by interpreting their life style. |
Phenotypic plasticity of elytron length in wingless two-spot ladybird beetles, Adalia bipunctata (Coleoptera: Coccinellidae)Suzanne T.E. LOMMEN, Peter W. DE JONG, Paul M. BRAKEFIELDEur. J. Entomol. 102 (3): 553-556, 2005 | DOI: 10.14411/eje.2005.079 Winglessness in the two-spot ladybird beetle Adalia bipunctata (L.) is determined by a single locus with the wingless allele recessive to the winged wildtype allele. The expression of the wingless trait is highly variable, with individuals missing a variable part of elytra and flight wings; the elytra and wings appear to be truncated rather than miniature in form. The degree of winglessness is partly determined genetically. Here we report on the phenotypic plasticity of the degree of winglessness. The environmental effect on elytron length relative to maximal elytron length in wingless phenotypes was studied by rearing offspring of single pair crosses of this form at a low (19°C) or high (29°C) temperature. Offspring reared at 19°C showed relatively longer elytra than those reared at 29°C. |
Species diversity and niche separation of cocoon parasitoids in different forest types with endemic populations of their host, the Common Pine Sawfly Diprion pini (Hymenoptera: Diprionidae)Annette HERZ, Werner HEITLANDEur. J. Entomol. 102 (2): 217-224, 2005 | DOI: 10.14411/eje.2005.034 Species diversity and potential impact of cocoon parasitoids on the abundance of the common pine sawfly, Diprion pini L. (Hymenoptera: Diprionidae), were explored in different forest habitats, with endemic sawfly populations, by the regular exposure of laboratory reared sawfly cocoons. Different cocoon spinning sites of the sawfly were simulated by exposing cocoons at several strata (soil, litter, trunk and stem of pine trees) in a forest. In more fertile, mixed spruce/pine-forests, parasitism on exposed cocoons was lower than in typical outbreak stands with a lower vegetational diversity. The parasitoid communities comprised of up to nine parasitoid species, which showed temporal and spatial niche separation. The ichneumonid Pleolophus basizonus Grav. (Hymenoptera: Phygadeuontinae) occured throughout the season at all strata as well as in all forest types. The ichneumonid Gelis cursitans F. (Hymenoptera: Phygadeuontinae) was only found in pine forests with sparsely developed ground vegetation, parasitizing exposed cocoons in the upper story in spring. The torymids Monodontomerus dentipes Dalm. (Hymenoptera: Torymidae) and M. minor Ratz. (Hymenoptera: Torymidae) were present in all forest types, but parasitized commonly only cocoons in the upper story in summer. Apparently, these generalists can quickly respond to increased densities of upper story exposed "summer" cocoons and thus limit the population growth of the pine sawfly due to the development of a second generation. |
Parasitoid complex and parasitism rates of the horse chestnut leafminer, Cameraria ohridella (Lepidoptera: Gracillariidae) in the Czech Republic, Slovakia and SloveniaLubomír VOLTER, Marc KENISEur. J. Entomol. 103 (2): 365-370, 2006 | DOI: 10.14411/eje.2006.049 The horse chestnut leaf miner, Cameraria ohridella Deschka & Dimić, is a species of unknown origin that recently invaded most of Europe, causing serious damage to horse chestnut trees, Aesculus hippocastanum. Parasitism was studied over a period of three years in the region of Plzeň in the Czech Republic. Additional collections were made in Slovakia and Slovenia. The parasitoid complex, dominated by polyphagous idiobiont parasitoids of the family Eulophidae, is similar to that found in other studies in Europe. Minotetrastichus frontalis (Nees) was the most abundant parasitoid found, except in Slovakia where Pediobius saulius (Walker) dominated. One parasitoid species, the eulophid Cirrospilus diallus (Walker) was recorded for the first time from C. ohridella. A new method is proposed to calculate stage-specific and total parasitism rates. Parasitism rates of spinning larvae and pupae were higher than of feeding larvae; however, total parasitism was low. We estimated that between 1% and 17% of moths died from parasitism during the larval and pupal stages whereas the rate of mortality caused by other factors varied from 7% to 62%, depending on the locality, year and generation. The proposed method for calculating total parasitism, based on the integration of stage-specific parasitism rates, which takes into account the mortality not directly attributed to parasitism, is discussed and compared with other methods commonly used in studies on C. ohridella. |
Biological and ecological studies on Scymnus syriacus and Scymnus levaillanti (Coleoptera: Coccinellidae)Thabet F. ALLAWIEur. J. Entomol. 103 (2): 501-503, 2006 | DOI: 10.14411/eje.2006.065 Both Scymnus syriacus Mars. and Scymnus levaillanti Muls. are aphidophagous coccinellids. In the laboratory they consumed and successfully reproduced on several species of aphids. Larvae suck the prey contents from aphid appendages, while adults consume the whole aphid, except for parts of the appendages. Extra-oral digestion is practiced during feeding. The mean number of aphids consumed by the larval stage of S. syriacus when reared at 25°C was 95, and 130 aphids at 30°C. For S. levaillanti it was 125 and 139 aphids at 25°C and 30°C, respectively. The mean number of eggs deposited daily by S. syriacus for the first three weeks of adult life was 19.5, with a range of 3-30 eggs at 25°C. Longevity of adults ranged from 3 to 4 months at 25°C and 2.5-3 months at 30°C. |
Increased xylem ingestion and decreased phloem ingestion in the aphid Acyrthosiphon pisum (Hemiptera: Aphididae) parasitised by Aphidius ervi (Hymenoptera: Braconidae)Claudio C. RAMÍREZ, Cristian A. VILLAGRA, Hermann M. NIEMEYEREur. J. Entomol. 103 (1): 263-265, 2006 | DOI: 10.14411/eje.2006.032 The effects of parasitisation by Aphidius ervi on the feeding behaviour of the aphid Acyrthosiphon pisum were studied. There was progressive increase in the time devoted to xylem ingestion (G waveform) and concomitant decrease in time devoted to phloem ingestion (E2 waveform) in parasitized relative to unparasitized aphids, as the time from parasitisation increased. These changes are interpreted as a way aphids compensate for metabolic changes occurring during parasitisation. |
Exploitation of kairomones and synomones by Medetera spp. (Diptera: Dolichopodidae), predators of spruce bark beetlesJiri HULCR, Marc POLLET, Karel UBIK, Jan VRKOČEur. J. Entomol. 102 (4): 655-662, 2005 The semiochemical relationships in a predator-prey-host plant system were studied by a series of multiple-choice field assays. The studied system included predatory flies of the genus Medetera (Diptera: Dolichopodidae), the bark beetles Ips typographus and Pityogenes chalcographus (Coleoptera: Curculionidae: Scolytinae) as prey and Norwegian spruce (Picea abies) as the host plant. Of the nine species of predators collected, only M. setiventris and M. melancholica provided sufficient data for statistical analysis. The response of the predators to monoterpenic products of the host (alpha-pinene, limonene, camphor), pheromone compounds of I. typographus (S-cis-verbenol and 2-methyl-3-buten-2-ol) and a mixture of the pheromones of I. typographus and P. chalcographus were investigated. Our field trials revealed that tree volatiles plus pheromones of the prey, and a pheromone mixture of both prey species were considerably more attractive to M. setiventris and M. melancholica than the individual chemicals. Medetera seem to respond to the stage of tree decay and the intensity of bark beetle infestation via the ratios of tree volatiles and/or prey pheromones. |
Effects and interactions of temperature, host deprivation and adult feeding on the longevity of the parasitoid Venturia canescens (Hymenoptera: Ichneumonidae)Panagiotis A. ELIOPOULOS, George J. STATHAS, Stelios L. BOURASEur. J. Entomol. 102 (2): 181-187, 2005 | DOI: 10.14411/eje.2005.029 A laboratory study was carried out to determine the effects and interactions of temperature, host deprivation and adult feeding on the longevity of the parasitoid Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae). The effect of body size was also examined. Large wasps (hind tibia length > 1.96 mm) lived significantly longer than smaller conspecifics (hind tibia length < 1.89 mm). Adults reared at 15°C lived longer regardless of whether supplied with hosts or food. Correspondingly, adults had a shorter life at 30°C. Honey-fed adults lived significantly longer than starved adults at all temperatures and irrespective of host presence, while access to hosts resulted in a decrease in longevity at all temperatures, regardless of food supply. The Weibull distribution was used to describe the age specific survival, which in V. canescens is of "Type I", as the risk of death increases with age. Despite the significant effect of host presence on survival it was less than either temperature or feeding. The interactions between feeding, host presence and temperature proved to be significant. The objective of the study was to improve the effectiveness of V. canescens as a biological control agent of stored product pests. |
Spatial variation in the incidence of a sexually transmitted parasite of the ladybird beetle Adalia bipunctata (Coleoptera: Coccinellidae)K. Mary WEBBERLEY, Matthew C. TINSLEY, John J. SLOGGETT, Michael E.N. MAJERUS, Gregory D.D. HURSTEur. J. Entomol. 103 (4): 793-797, 2006 | DOI: 10.14411/eje.2006.108 Whilst sexually transmitted pathogens and parasites are common on insects and other animals, the factors affecting their incidence are currently uncertain. In order to understand the factors important in determining the presence of sexually transmitted parasites, it would be helpful to have information on intraspecific variation in incidence, as the causes of this variation are likely to reflect the likely causes of the presence/absence of sexually transmitted parasites across species. We therefore mapped the incidence of the parasite Coccipolipus hippodamiae within Europe on its primary host, the ladybird Adalia bipunctata. We observed that C. hippodamiae was present widely in Central, Southern and Eastern Europe, but was absent from northerly and north-western populations. The cause of this pattern of incidence variation is discussed, with particular reference to the voltinism of the host. We also note that the distribution of C. hippodamiae on A. bipunctata is not congruent with that of another sexually transmitted parasite of this species, Hesperomyces virescens. |
Resource guarding by Ptomascopus morio: Simple parental care in the Nicrophorinae (Coleoptera: Silphidae)Seizi SUZUKI, Masahiro NAGANOEur. J. Entomol. 103 (1): 245-248, 2006 | DOI: 10.14411/eje.2006.027 Nicrophorine beetles use small vertebrate carrion for breeding resource. While Nicrophorus spp. have highly developed biparental care, no form of parental care is recorded for Ptomascopus spp. We examined two effects of resource guarding by Ptomascopus morio. The presence of parents, especially the female, reduced the number of fly larvae on chicken carrion. Parents also enhanced the survival of brood faced with predation by the rove beetle, Ontholestes gracilis. In 6 out of 20 trials, the rove beetle predators were killed by Ptomascopus morio parents. We conclude that Ptomascopus morio has a simple, and possibly primitive form of parental care. |
Oviposition at low temperatures - late season negatively affects the leaf beetle Galeruca tanaceti (Coleoptera: Galerucinae) but not its specialised egg parasitoid Oomyzus galerucivorus (Hymenoptera: Eulophidae)Torsten MEINERS, Barbara RANDLKOFER, Elisabeth OBERMAIEREur. J. Entomol. 103 (4): 765-770, 2006 | DOI: 10.14411/eje.2006.103 Insects experience important selection pressures from their parasitoids, which affect both their population dynamics and their evolutionary responses. The interaction between the egg parasitoid Oomyzus galerucivorus Graham (Hymenoptera: Eulophidae) and its chrysomelid host Galeruca tanaceti L. (Coleoptera: Galerucinae) was investigated with the particular aim determining whether the chrysomelid host can escape its parasitoid by ovipositing late in the year as early as September. Although the leaf beetle and its parasitoid emerge in April, G. tanaceti starts to oviposit after spending the summer in reproductive diapause. The objective was to determine, whether the small parasitic wasp can parasitise its host's eggs even at the end of its host's reproductive season in December, when temperatures are low. Beetle oviposition, parasitism rates and temperatures were measured on three comparable mesoxerophytic grassland sites over the coarse of a season. Beetle oviposition, but not parasitism, was significantly positively dependent on temperature. Rate of oviposition decreased over the oviposition period with decrease in temperature. In contrast, after a lag phase of 1-2 weeks at the beginning of the oviposition period in September beetle egg clutches were parasitised at a constant rate until the end of the season in December. Host eggs were parasitised even at mean daily temperatures of 0-6°C. Thus the tansy leaf beetle does not escape from egg parasitism by ovipositing late in the season in central Germany. |
Haemolymph amino acid, sugar and glycerol levels in the Namib Desert tenebrionid Physadesmia globosa (Coleoptera: Tenebrionidae) during dehydration and rehydrationStrinivasan G. NAIDUEur. J. Entomol. 103 (2): 305-310, 2006 | DOI: 10.14411/eje.2006.039 Haemolymph levels of amino acids, sugars and glycerol were investigated in the tenebrionid Physadesmia globosa during dehydration and rehydration. The absolute amount of amino acid decreases during dehydration and increases during rehydration, indicating active regulation of this solute (the osmolal contribution of amino acids is large - approx. 25%). Changes in the amino acid content of the haemolymph during dehydration are not the result of interchange with soluble protein; the possibility exists during rehydration (between 1 h and 48 h). Trehalose and glucose are the only sugars found in appreciable quantity in the haemolymph of this species. Their osmolal contributions (total sugar: 2.6%), and contributions to osmoregulation, are not great. Glycerol is a minor osmolar effector in the haemolymph of Physadesmia, and changes in its levels do not contribute importantly to the regulation of haemolymph osmotic pressure. |
Molecular insights into speciation in the Agrilus viridis-complex and the genus Trachys (Coleoptera: Buprestidae)Detlef BERNHARD, Guido FRITZSCH, Pia GLÖCKNER, Claus WURSTEur. J. Entomol. 102 (4): 599-605, 2005 Species of the Agrilus viridis-complex and the genus Trachys are morphologically difficult to identify or even indistinguishable. However, all of them are ecologically clearly separated because their larvae develop in different host plants. Hitherto, it was unclear whether they represent varieties, ecological races or true species. In this paper the genetic variation and phylogenetic relationships within these groups are analysed using partial sequence data from mitochondrial genes (12S rDNA, and a fragment containing regions of ND1 and 16S rDNA). The phylogenetic analyses yielded largely congruent tree topologies and indicate that all species and varieties of the Agrilus viridis-complex belong to a monophyletic group, which is closely related to A. cuprescens. Compared to all other Agrilus-species tested, the genetic distances within the A. viridis-complex are very small. However, all varieties and species are clearly separated. Thus, our data support the view that both the members of the Agrilus viridis-complex and the species of the Trachys-group represent genetically separated taxa. |
Seasonal wing dimorphism and life cycle of the mole cricket Gryllotalpa orientalis (Orthoptera: Gryllotalpidae)Chihiro ENDOEur. J. Entomol. 103 (4): 743-750, 2006 | DOI: 10.14411/eje.2006.098 Control of seasonal wing dimorphism in the oriental mole cricket Gryllotalpa orientalis Brumeister (1839) from a wetland habitat in western Japan is described. The long-winged (LW) morph appeared from mid-June to September, whereas the short-winged (SW) morph appeared from September to mid-June. Individuals overwintered in either the adult or juvenile stage. The seasonal shift in wing morphology was linked to the overwintering stage. Individuals that hatched in May became SW adults in September-October and then overwintered, whereas those that hatched in June and July overwintered as juveniles and became LW adults in June of the following year. The life cycle of both morphs was univoltine. Reproductive benefits and constraints of each wing morph of G. orientalis are compared. |
Phoretic relationships between Uropodina (Acari: Mesostigmata) and centipedes (Chilopoda) as an example of evolutionary adaptation of mites to temporary microhabitatsJerzy BŁOSZYK, Joanna KLIMCZAK, Małgorzata LE¦NIEWSKAEur. J. Entomol. 103 (3): 699-707, 2006 | DOI: 10.14411/eje.2006.093 A survey of soil fauna in Poland revealed 30 cases of centipedes carrying mites of the sub-order Uropodina. The 155 phoretic deutonymphs collected belonged to two species of Uropodina - Oodinychus ovalis (C.L. Koch, 1839) and Uroobovella pulchella (Berlese, 1904). These mites displayed a high degree of selectivity in their choice of carrier. The only species of centipede transporting mites was Lithobius forficatus (Linnaeus, 1758), despite the presence of 30 other species in the same habitats. It is possible that the large size and relatively fast speed of movement of this centipede make it a very good mite carrier. The majority of the mites were located on the sides of the centipedes, on segments near the anterior end. The high selectivity in the choice of carrier as well as the point of attachment suggests adaptation by the mites for phoresy by L. forficatus. |
Responses of Sitophilus oryzae (Coleoptera: Curculionidae) and Tribolium confusum (Coleoptera: Tenebrionidae) to traps baited with pheromones and food volatilesChristos G. ATHANASSIOU, Nickolas G. KAVALLIERATOS, Pasquale TREMATERRAEur. J. Entomol. 103 (2): 371-378, 2006 | DOI: 10.14411/eje.2006.050 The behavioural responses of two species of stored-product beetles, Sitophilus oryzae (L.) and Tribolium confusum Jacquelin du Val, to certain stimuli were studied in laboratory choice tests. The results of these experiments indicated that, with one species present, S. oryzae and T. confusum adults were equally attracted to traps baited with the aggregation pheromone of that species and to traps baited with both pheromones. In contrast, when both species were present, neither S. oryzae nor T. confusum showed specific behavioural trend towards a stimulus. Traps baited with 1 g of a mixture of plant extracts were significantly more attractive for both species than unbaited traps, but this response was highly influenced by the number of individuals of each species released. Traps baited with filter papers that were previously contaminated by live adults of both species were particularly attractive for S. oryzae, but not for T. confusum. Traps that contained 10 seeds damaged by S. oryzae were significantly more attractive than traps containing an oil lure or control traps for S. oryzae, but not for T. confusum. The addition of oil to the seeds did not affect the attractiveness of the trap for S. oryzae. Traps that contained 20 live S. oryzae adults were significantly more attractive than traps containing 20 dead S. oryzae adults or control traps. No significant differences were noted between traps containing 20 dead S. oryzae adults and control traps. The presence of S. oryzae adults in traps did not affect the response of T. confusum. |
Phenylacetaldehyde: A chemical attractant for common green lacewings (Chrysoperla carnea s.l., Neuroptera: Chrysopidae)Miklós TÓTH, András BOZSIK, Ferenc SZENTKIRÁLYI, Agostino LETARDI, Maria Rosaria TABILIO, Marcello VERDINELLI, Pietro ZANDIGIACOMO, Judit JEKISA, István SZARUKÁNEur. J. Entomol. 103 (1): 267-271, 2006 | DOI: 10.14411/eje.2006.033 At five sites in Hungary and Italy, traps baited with phenylacetaldehyde caught significantly higher numbers (10 to 100 times more) of green lacewings than unbaited traps, which demonstrates that this compound is an attractant. Traps with three bait dispensers usually caught more than those with one dispenser, but the difference was significant only at two out of five test sites. There was no difference in the numbers caught by sticky delta and funnel traps baited with phenylacetaldehyde. However, funnel traps could be adapted to catch living green lacewings. The vast majority of the specimens belonged to the Chrysoperla carnea species complex. Ch. carnea sensu lato dominated the catches at all sites. At some sites 3-11% of the insects caught were Ch. lucasina Lacroix. Phenylacetaldehyde-baited traps were attractive to both sexes, but generally more females were caught than males. Funnel traps baited with three dispensers of phenylacetaldehyde caught green lacewing adults throughout the season in Hungary. |
Evolution of prey specialization in aphidophagous syrphids of the genera Melanostoma and Platycheirus (Diptera: Syrphidae) 1. Body size, development and prey traitsFrank DZIOCKEur. J. Entomol. 102 (3): 413-421, 2005 | DOI: 10.14411/eje.2005.059 Interactions between syrphid predators and their prey are poorly known. The adaptations of syrphids to aphid defences and the consequences for the evolution of life history traits in these predators especially are mostly unstudied. This is the first of two papers investigating the evolution of prey specialization in aphidophagous hoverflies. The study focuses on two questions: (1) Are differences in the body size of syrphid predators reflected in differences in the size of their prey? (2) Are differences in body size, body mass and development time of the syrphid predators correlated with the defence strategies of their aphid prey (e.g. mobility, toxicity)? Platycheirus clypeatus (Meigen, 1822), Platycheirus fulviventris (Macquart, 1829), Melanostoma mellinum (Linnaeus, 1758), and Melanostoma scalare (Fabricius, 1794), which differ considerably in their prey specialization, but are closely related, were chosen as model species. Life history data for these syrphids came from a laboratory study, and that for the aphids from a literature survey. These syrphid species can be arranged on a gradient of increasing prey specialization, from 32 prey species for the generalist M. mellinum and only 3 for the specialist P. fulviventris. Differences in prey specialization were even more evident when the defence ability of the various species of aphid prey was considered. For instance, the specialization on ant-attended aphids in M. scalare. Larvae exhibited a one or two weeks diapause which made the determination of developmental time imprecise. Body size of the predators was not reflected in that of their aphid prey. The postulated relationship between body size of the predator and the defence strategies of their prey was not supported by our data. A comparison of a wider range of syrphid species from different taxonomic groupings together with a phylogenetic correction procedure might reveal clearer trends. The second part of this paper (Dziock, in prep.) will investigate the correlation between prey specialization and reproductive strategies (i.e. clutch size, egg size and number) and will put the results into a broader framework. |
The effect of heat stress on the activity of A1 and A2 neurosecretory neurons of Morimus funereus (Coleoptera: Cerambycidae) larvaeSneľana LEKOVIĆ, Jelica LAZAREVIĆ, Vera NENADOVIĆ, Jelisaveta IVANOVIĆEur. J. Entomol. 98 (1): 13-18, 2001 | DOI: 10.14411/eje.2001.002 A study on the effect of heat stress on the activity of the medial A1 and A2 neurosecretory neurons (NSN), and the activity of midgut a-amylase and protease was performed on the fifth larval instar of Morimus funereus. Exposure of the larvae to 35°C led to a decrease in the activity of both A1 and A2 NSN, the former being more marked than the latter. These neurons responded differently to heat stress in terms of neurosecretory material synthesis and release. The changes in the size of both A1 NSN and their nuclei and protease activity in the larvae exposed to elevated temperature were significantly correlated, which suggests that A1 NSN play a role in the regulation of the activity of this enzyme during heat stress. The significant correlations between the size of A2 NSN and protease activity in the controls, and the size of both A2 NSN and their nuclei and amylase activity in larvae exposed to heat stress, similarly may mean that A2 NSN regulate both digestive enzyme activities depending on environmental temperature. |
The role of crop density, seed and aphid presence in diversification of field communities of Carabidae (Coleoptera)Alois HONĚK, Vojtěch JARO©ÍKEur. J. Entomol. 97 (4): 517-525, 2000 | DOI: 10.14411/eje.2000.080 In 1995-1997, we studied the factors which may influence the ground "activity density" of Carabidae using pitfall traps placed in winter wheat, winter rape and pea stands (1995 only) grown within a 1 km2 area with uniform physical conditions. The traps were placed in plots of bare ground established within the crops and under surrounding intact plant stands. The communities were similar between crops within years (Pearson's correlation coefficient r = 0.60 - 0.81), and between years within crops (r = 0.89 - 0.91), except for the poor winter rape stand in 1997. Factors influencing carabid "activity density" were: (i) Density of crop stand. The carabids preferred crop-shaded ground as long as crop density was low or medium but moved to bare ground plots when crop density became high. Under moderate crop density the preference differed between beetle species, most of which preferred crop-shaded ground while a few ones preferred bare ground. Carabid preferences were probably determined by microclimatic differences caused by presence and density of crop cover. (ii) Presence of seeds dropped on the ground. In rape stands, presence of crop and weed seeds increased the "activity density" of seed predators (species of genera Amara, Harpalus, Ophonus and Pseudoophonus). Scattering of rape seeds significantly increased local activity density of Harpalus affinis and H. distinguendus in the wheat stand. (iii) Presence of aphids. Activity density of Bembidion lampros and Trechus quadristriatus and between-year variation in pooled abundance of the five species recognised as aphid predators was associated with variation in aphid abundance. |
Prevalence and association of the laboulbenialean fungus Hesperomyces virescens (Laboulbeniales: Laboulbeniaceae) on coccinellid hosts (Coleoptera: Coccinellidae) in Kentucky, USAJames D. HARWOOD, Carlo RICCI, Roberto ROMANI, Kevin M. PITZ, Alex WEIR, John J. OBRYCKIEur. J. Entomol. 103 (4): 799-804, 2006 | DOI: 10.14411/eje.2006.109 The laboulbenialean fungi occur throughout the world and are closely associated with a range of arthropods, including many coleopteran hosts. Throughout the summer of 2004, coccinellids were collected from a Bluegrass savanna woodland ecosystem, dominated by blue ash Fraxinus quadrangulata and Chinkapin Oak Quercus muehlenbergii, and the adults were examined for the presence of Hesperomyces virescens using binocular and scanning electron microscopy. Over 80% of adult Harmonia axyridis, a species previously reported as having a persistent association with the fungus, were infected. No significant differences were observed in incidence on male and female hosts, however, the distribution of fungus differed between sexes. Female H. axyridis had a greater percentage of infection on their elytron compared to other parts of their body whilst male infection was concentrated around their elytra, legs and abdomen. Although infection rates were significantly lower, we report, for the first time, the presence of this fungus on the hosts Cycloneda munda, Brachiacantha quadripunctata and Psyllobora vigintimaculata. This is the first study documenting the incidence of this insect-associated fungus with these native coccinellids of North America. In the samples collected from the Bluegrass savanna, two species (Coleomegilla maculata and Hyperaspis signata) were not infected by this fungus. |
Types of haemocytes in saprophagous soil mites (Acari: Oribatida, Acaridida), and the correlation between their presence and certain processes within mitesJaroslav SMR®Eur. J. Entomol. 103 (3): 679-686, 2006 | DOI: 10.14411/eje.2006.088 The microanatomy of several oribatid and one acaridid mite was studied to determine the role of free cells (haemocytes) in mites. Mites from the field as well as laboratory cultures were observed and analyzed histologically using Masson triple stain. The mites were offered various foods and kept in fluctuating moisture conditions. The presence of haemocytes was significantly correlated with the transport between internal organs of various substance. Three types of transport were recorded: (i) enzymes into the alimentary tract, including the incorporation of haemocytes into the gut walls. This process seemed to be correlated with the amount and type of food and frequently with the presence of internal extraintestinal bacteria associated with mesenchyma; (ii) metabolites, like guanine from mesenchyma into the alimentary tract followed by expulsion from the body via the gut. This process is correlated with food of high nitrogen content or dry conditions; (iii) resorption of nutrients from eggs during an induced quiescent state under unfavourable conditions by small haemocytes. |
Phaenoglyphis "versus" Hemicrisis, and the description of a new sculptured species of Charipinae (Hymenoptera: Figitidae)Juli PUJADE-VILLAR, Jordi PARETAS-MARTÍNEZEur. J. Entomol. 103 (2): 477-481, 2006 | DOI: 10.14411/eje.2006.061 After comparing the morphology of the genus Hemicrisis Förster, 1869 and Phaenoglyphis Förster, 1869, and examining the sculpturing in this genus, the synonymy between Hemicrisis and Phaenoglyphis is re-established. The specific status of Phaenoglyphis pubicollis (Thomson, 1877) comb. n. is re-established and differentiated from Phaenoglyphis ruficornis (Förster, 1869) comb. n. A new species of Charipinae, Phaenoglyphis evenhuisi sp. n. is described from Andorra. It is characterized by the presence of sculpture on the mesonotum, a character only shared with P. pubicollis. Some illustrations are provided. Notes on all the sculptured Charipinae are provided as well as a key to the genera of Alloxystini. |
Short-term consequences of nutritional depression on foraging behaviour of dark bush-crickets Pholidoptera griseoaptera (Orthoptera: Ensifera)Steffen HAHN, Grit KUNERTEur. J. Entomol. 103 (1): 249-253, 2006 | DOI: 10.14411/eje.2006.028 Temporary malnutrition during juvenile development often negatively influences the life-history decisions of adults. Hence, individuals should avoid this effect by compensatory feeding on the limited resource when the food situation improves. In a feeding experiment, bush-crickets (Pholidoptera griseoaptera) responded to nine days depression of animal food supply by increasing their feeding activities on insect carcasses when a full-nutritional diet was available. As a short-term reaction, treated individuals of both sexes took 3.4 times more food from carcasses (0.084 g / 9 h) than control individuals. The increased carcass intake levelled off at 0.025 g / 9 h after an interval of nine hours, indicating that bush-crickets can rapidly compensate for an experimentally increased demand for animal diet. The general daily carcass intake of male and female bush-crickets was 0.07 g fresh weight, corresponding to 16.4% of the bush-cricket's body mass. Carcass intake and body mass development was correlated over the complete period (7 d), but no correlation was found for the time of short-term reaction. We conclude that animal diet is essential for the growth of dark bush-crickets. They were able to compensate for short depressions in animal food supply by increasing feeding frequencies and feeding rates of the limited resource. Hence, bush-crickets can cope with short periods of limited animal food supply, e.g. periods of rainfall, which regularly occur in their natural habitat. |
Pljushtchia prima, new moth genus and species from Tadjikistan (Lepidoptera: Geometridae)Jaan VIIDALEPP, Igor KOSTJUKEur. J. Entomol. 102 (4): 777-785, 2005 A new genus and species of geometrid moths from Tadjikistan is described and its position in the taxonomic structure of the subfamily Larentiinae is analysed. The new genus is grouped, based on the parsimony analysis of 38 morphological characters, to coniferous-feeding genera of the tribe Cidariini as follows: (Thera (Pennithera (Protothera (Pljushtchia gen. n. Heterothera)))). Pljushtchia is characterised by the antennae, unipectinate in males and flat, serrate in females, by a reduced haustellum, the venation of wings and the structure of the genitalia. The Thera firmata species group is validated as a genus Protothera. The tribe Cidariini includes four groups of related genera and is most speciose in southeastern Asia. |
The spatial distribution of leaf galls of Mikiola fagi (Diptera: Cecidomyiidae) and Neuroterus quercusbaccarum (Hymenoptera: Cynipidae) in the canopy of a Central European mixed forestChristian KAMPICHLER, Markus TESCHNEREur. J. Entomol. 99 (1): 79-84, 2002 | DOI: 10.14411/eje.2002.014 Despite their wide distribution and frequent occurrence, the spatial distribution patterns of the well-known gall-inducing insects Mikiola fagi (Hartig) and Neuroterus quercusbaccarum (L.) in the canopies of mature trees are poorly described. We made use of the Swiss Canopy Crane (SCC) near Basel, Switzerland, to gain access to the canopy of a mixed temperate forest up to a height of 35 m. Within one and a half days we scanned 6,750 beech leaves and 6,000 oak leaves. M.fagi showed a distinct vertical zonation with highest abundance in the top-most parts of the canopy as well as a significant aggregation on particular trees. N. quercusbaccarum showed an even more pronounced preference for particular trees and a general preference for Quercus robur over Q. petraea. In contrast to M. fagi, no vertical zonation could be detected. We think that both gall-inducing species have greater powers of dispersal than formerly assumed since they overwinter on the forest floor and yet are able to 1) gain access to the entire canopy, 2) show preference for certain host trees. We found little evidence for the phenological synchrony hypothesis proposed to explain the intertree distribution of N. quercusbaccarum. The highest density of M. fagi galls was in those parts of the canopy exposed to high solar radiation; their host choice is probably determined by micro-climatological factors. The consequences of the distribution patterns of N. quercusbaccarum and M. fagi for their ecological interactions with the host-plant, inquilines and parasitoids (e.g., canopy-layer specific performance linked to plant chemistry, density-dependent parasitism) need now to be subjected to further scientific investigation. |