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Effect of population density on the development of Mesovelia furcata (Mesoveliidae), Microvelia reticulata and Velia caprai (Veliidae) (Heteroptera: Gerromorpha)Tomáš DITRICH, Miroslav PAPÁČEKEur. J. Entomol. 107 (4): 579-587, 2010 | DOI: 10.14411/eje.2010.067 Population density during nymphal development affects body size, developmental rate and wing polymorphism in semiaquatic bugs. Nymphs from crowded habitats grow faster and thus gain an advantage in the later stadia. Rapid development results in smaller body size in several gerrids. Macropterous adults develop more frequently at high population densities in most species, which enables the bugs to leave crowded habitats. Three European widespread species Mesovelia furcata Mulsant & Rey, 1852 (Mesoveliidae), Microvelia reticulata Burmeister, 1835 and Velia caprai Tamanini, 1947 (Veliidae) were reared individually and simultaneously either at a low or high population density. Duration of postembryonic development, wing morph, body size and length of distal oocyte in females were recorded. High population density accelerates development in Mesovelia furcata and Microvelia reticulata. However, there was no trade-off between developmental rate and body size. Accelerated development without a decrease in body size was probably because maturation was delayed. Individually reared nymphs developed faster than nymphs from communal cohorts. No long-winged Microvelia reticulata specimen developed in any treatment. However, more macropterous individuals developed in high-density treatments in Mesovelia furcata (significant) and Velia caprai (not significant). All the nymphs of the species that were reared individually developed into apterous adults. The results suggest that population density strongly influences the life history of semiaquatic bugs. However, the only commonly shared response seems to be an increase in developmental rate when reared at high population densities. Other traits such as wing dimorphism, body size and rate of oogenesis differ at the species level. |
A molecular phylogeny of Polyommatus s. str. and Plebicula based on mitochondrial COI and nuclear ITS2 sequences (Lepidoptera: Lycaenidae)Martin WIEMERS, Boris V. STRADOMSKY, Dmitrij I. VODOLAZHSKYEur. J. Entomol. 107 (3): 325-336, 2010 | DOI: 10.14411/eje.2010.041 The phylogenetic relationships of the subgenera Polyommatus and Plebicula, within the Palaearctic butterfly genus Polyommatus, were inferred from a combined analysis of the nuclear marker ITS2 and the barcoding section of the mitochondrial gene COI. Eight major clades were recovered within Polyommatus s. l., which correspond closely to subgenera based on traditional systematics and are of late Pliocene to early Pleistocene origin. Extraordinary chromosomal evolution occurred independently in three of these clades. The disputed position of several species formerly placed in the subgenus Plebicula is clarified. A group of Central Asian species (Bryna) was recovered as a monophyletic clade within Polyommatus s. str. The Kurdistanian endemic P. buzulmavi appears as a sister species to P. icarus. P. celina replaces P. icarus in NW Africa and the Canary Islands, and split from the last common ancestor with P. icarus back in the early Pleistocene. |
Genetic polymorphism in "mixed" colonies of wood ants (Hymenoptera: Formicidae) in southern Finland and its possible originJulita KORCZYŃSKA, Marta GAJEWSKA, Malgorzata PILOT, Wojciech CZECHOWSKI, Alexander RADCHENKOEur. J. Entomol. 107 (2): 157-167, 2010 | DOI: 10.14411/eje.2010.021 Wood ant colonies that appear to consist of individuals representing different species are described in several previous papers. The present study is the first to elucidate the genetic basis of the spectacular morphological variability observed within such colonies. Two seemingly mixed colonies (FM-1 and FM-2) from southern Finland were investigated. On the basis of the morphology of their workers these colonies were comprised of individuals with phenotypes typical of Formica rufa L., F. polyctena Först., and F. aquilonia Yarr. The sequence of an mtDNA fragment (5' end of the cytochrome b gene) was used to examine the phylogenetic relationships among haplotypes of workers from homogeneous colonies of different wood ant species and the two supposedly mixed colonies, and to sort the individuals within the colonies into matrilines. Six microsatellite loci were used to analyse the genetic differentiation between colonies and among workers within colonies, and to detect putative hybrids. The results show that, independently of their phenotype, workers from the "mixed" colonies were genetically more similar to other individuals in their colony than to those in the homogeneous F. rufa, F. polyctena or F. aquilonia colonies. However, while colony FM-1 consisted of offspring of the same queen or more likely several maternally related queens, colony FM-2 consisted of the offspring of at least four unrelated queens. The data suggest hybridisation between F. polyctena × F. aquilonia and F. polyctena × F. rufa (and possibly subsequent mating between these hybrids) as the most probable mechanism leading to the existence of these two colonies, which implies that the hybrids are fertile. This study shows that colonies of wood ant hybrids can arise spontaneously and persist under natural conditions. The results also revealed that even some morphologically homogeneous colonies are genetically heterogeneous. In the case of closely related, morphologically similar species that interbreed, morphology can be a bad predictor of genetic differences between individuals. |
Artificial diet for two flat-headed borers, Capnodis spp. (Coleoptera: Buprestidae)Galina GINDIN, Tatiana KUZNETSOVA, Alexei PROTASOV, Shaul Ben YEHUDA, Zvi MENDELEur. J. Entomol. 106 (4): 573-581, 2009 | DOI: 10.14411/eje.2009.072 The main objective was to develop an artificial diet for two flat-headed borers, Capnodis tenebrionis L. and C. carbonaria Klug. (Coleoptera: Buprestidae), which are severe pests of stonefruit plantations in the Mediterranean basin. The effect of proteins from various sources, percentage of cortex tissue in the diet and diet structure on larval growth and survival were investigated. The most successful diet contained 2.8% casein and 4.6% dry brewer's yeast as the protein source. For complete larval development and successful pupation it is essential to include cortex tissue from the host plant in the diet. Mean larval development time was shortened by 10-12 days when reared on a diet containing 20% cortex tissue compared with rearing on diet containing 10% cortex tissue. Two different diet structures were required, a viscous matrix for the first and second instar larvae and drier crumbly diet, which allows the larvae to move within the diet, for older larvae. At 28°C on the artificial diet C. tenebrionis and C. carbonaria completed their development in 2-2.5 months compared to the 6-11 months recorded in Israeli orchards. C. tenebrionis successfully completed two generations on the artificial diet. |
Good-bye Scydmaenidae, or why the ant-like stone beetles should become megadiverse Staphylinidae sensu latissimo (Coleoptera)Vasily V. GREBENNIKOV, Alfred F. NEWTONEur. J. Entomol. 106 (2): 275-301, 2009 | DOI: 10.14411/eje.2009.035 Ant-like stone beetles (Coleoptera: Scydmaenidae) include more than 4,850 described species in about 90 genera maintained as a separate cosmopolitan family since 1815. Recent authors have hypothesised that Scydmaenidae might be rooted deep inside rove-beetles (Staphylinidae). To test this hypothesis we analysed 206 parsimoniously informative larval and adult morphological characters scored for 38 taxa. Strict consensus topologies from the shortest trees in all 12 analyses consistently placed Scydmaenidae as sister to (Steninae + Euaesthetinae) in a monophyletic Staphylinine Group (with or without Oxyporinae). The single fully resolved and most consistently supported topology maintains a monophyletic Staphylinine Group consisting of Oxyporinae + (Megalopsidiinae + (("Scydmaenidae" + (Steninae + Euaesthetinae)) + (Leptotyphlinae + (Pseudopsinae + (Paederinae + Staphylininae))))); Solierius lacks larval data and is ambiguously placed within the Group. Eight analyses of variably aligned 18S rDNA data for 93 members of Staphylinoidea under parsimony, neighbour-joining and Bayesian approaches were markedly inconsistent, although partly congruent with the Scydmaenidae + (Steninae + Euaesthetinae) hypothesis. Our results strongly suggest that ant-like stone beetles do not form an independent family, but are morphologically modified members of Staphylinidae and, consequently, should be treated as a 32nd recent subfamily within the megadiverse Staphylinidae sensu latissimo. Formal taxonomic acts are: Scydmaeninae Leach, 1815, status novus (= Scydmaenidae Leach, 1815); Scydmaenitae Leach, 1815, status novus (= Scydmaeninae Leach, 1815); Mastigitae Fleming, 1821, status novus (= Mastiginae Fleming, 1821); Hapsomelitae Poinar & Brown, 2004, status novus (= Hapsomelinae Poinar & Brown, 2004). The family Staphylinidae sensu latissimo becomes the largest in Coleoptera and in the whole of the Animal Kingdom, with 55,440 described species (extant plus extinct), thus surpassing Curculionidae with an estimated 51,000 described species. |
Photoperiodic control of development and reproduction in Harmonia axyridis (Coleoptera: Coccinellidae)Sergey Ya. REZNIK, Nina P. VAGHINAEur. J. Entomol. 108 (3): 385-390, 2011 The effects of photoperiod on pre-imaginal development and reproductive maturation of adult females of the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), were investigated at 20°C and at photoperiods from 10L : 14D to 18L : 6D. Experiments were conducted on a laboratory strain that originated from the Russian Far East. Larvae and adults were fed on the green peach aphid Myzus persicae. Under short day conditions the pre-imaginal development was faster than under long day conditions. The acceleration of pre-imaginal development occurred when day length was shorter than 16 h and the threshold day length was ca 14 h. The rate of reproductive maturation of adult females, in contrast, was twice as high under long day conditions, with the threshold between 14L : 10D and 12L : 12D, although even under short day conditions ca 10% of the females show a tendency to mature more quickly. This difference between the thresholds of these two photoperiodic reactions indicates they are relatively independent of one another. |
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. |
Species coexistence patterns in a mycophagous insect community inhabiting the wood-decaying bracket fungus Cryptoporus volvatus (Polyporaceae: Basidiomycota)Kohmei KADOWAKIEur. J. Entomol. 107 (1): 89-99, 2010 | DOI: 10.14411/eje.2010.012 A study of the insect community inhabiting the wood-decaying bracket fungus, Cryptoporus volvatus was used to test two hypotheses proposed to account for the competitive coexistence of species in insect communities in patchy environments, niche partitioning and spatial mechanisms. A total of 8990 individuals belonging to 17 insect species emerged from 438 sporocarps (patches) collected from the field. Insect species richness increased and then declined with increase in the total insect biomass reared from a sporocarp, suggesting the potential importance of interspecific competition. Successional niche partitioning explained the spatial distribution of the four specialist species. The aggregation model of coexistence satisfactorily explained the stable coexistence of the species. The specialist species displayed higher population persistence than the generalists. Simulation studies suggest that restricted movements of adults could override patch-level larval aggregation. The effect of such restricted movements on stabilizing coexistence in fungus-insect communities has not been previously appreciated. These findings suggest that spatial mechanisms play a crucial role in the competitive coexistence of the species in the mycophagous insect communities inhabiting bracket fungi. |
Chilocorus renipustulatus (Coleoptera: Coccinellidae) dominates predatory ladybird assemblages on Sorbus aucuparia (Rosales: Rosaceae)Emanuel KULA, Oldřich NEDVĚDEur. 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. |
Deterrence of feeding in Rhodnius prolixus (Hemiptera: Reduviidae) after treatment of antennae with a nitric oxide donorValeria SFARA, Eduardo N. ZERBA, Raúl A. ALZOGARAYEur. J. Entomol. 108 (4): 701-704, 2011 | DOI: 10.14411/eje.2011.089 The blood-sucking bug Rhodnius prolixus is the main vector of Chagas Disease in Colombia, Venezuela and several countries in Central America. Nitric oxide (NO) is a ubiquitous gaseous molecule present in most types of cell and participates in the olfactory pathway of insects. In this work, nitroso-acetyl-cysteine (SNAC), a nitric oxide donor, was topically applied to the antennae of fifth instar nymphs of R. prolixus. After SNAC treatment, these insects showed a dose-dependent reluctance to feed when provided with a living pigeon as the food source (ED50 = 5.2 µg/insect). However, there was no reluctance to feed when db-cGMP was applied to the antennae of nymphs. In another experiment, insects that had their antennae treated with SNAC were less attracted than the control group to a CO2 source. A possible role of NO in the olfactory pathway of R. prolixus is discussed. |
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. |
Molecular approach for identification of mosquito species (Diptera: Culicidae) in Province of Alessandria, Piedmont, ItalyAsghar TALBALAGHI, Elena SHAIKEVICHEur. J. Entomol. 108 (1): 35-40, 2011 | DOI: 10.14411/eje.2011.004 The aim of the present work was to identify cryptic species in the Anopheles maculipennis and Culex pipiens complexes and to study the genetic structure of the dominant mosquito species Ochlerotatus caspius (Diptera: Culicidae) in the Province of Alessandria close to the vast area untreated rice fields in Piedmont, NW Italy. With the help of PCR-RFLP analysis, four members of the Anopheles maculipennis complex were identified: A. messeae, A. maculipennis, A. sacharovi and A. atroparvus. Only C. pipiens f. molestus was identified in 11 habitats studied in Piedmont. Partial sequences of the cytochrome c oxidase subunit 1 (COI) mitochondrial gene and the second internal transcribed spacer (ITS2) of nuclear ribosomal RNA genes for Italian O. caspius are reported here for the first time. The results indicate that this species diverged from Iranian representatives of this species about one million years ago. The great diversity of mosquito species in Piedmont considerably increases the risk of vector-borne diseases. |
Universal primers for amplifying the complete coding sequence of cytoplasmic heat shock protein 90 (HSP90) in LepidopteraPeng Jun XU, Tong LI, Jin Hua XIAO, Robert W. MURPHY, Huang DA WEIEur. J. Entomol. 108 (1): 164-168, 2011 | DOI: 10.14411/eje.2011.020 Using sequence alignment, a conserved domain in the 3' untranslated region (UTR) of the cytoplasmic heat shock protein 90 (HSP90) of Lepidoptera was found. This region is highly variable in other insect groups. Furthermore, universal primers were designed to amplify the complete coding sequence (CDS) of HSP90 from total genomic DNA in Lepidoptera, avoiding the commonly used reverse transcription-polymerase chain reaction (RT-PCR) and 3', 5'-rapid amplification of cDNA ends (RACE) methods based on cDNA. These primers amplified a fragment of about 2.25 kb in the 11 species tested, which represent seven different families of Lepidoptera, including moths and butterflies. The results suggest that the conserved domain of 3'UTR is universal in Lepidoptera and these primers successfully amplify the complete CDS of cytoplasmic HSP90 from genomic DNA. |
Host recognition and acceptance behaviour in Cotesia sesamiae and C. flavipes (Hymenoptera: Braconidae), parasitoids of gramineous stemborers in AfricaMeshack OBONYO, Fritz SCHULTHESS, Bruno LE RU, Johnnie VAN DEN BERG, Paul-André CALATAYUDEur. J. Entomol. 107 (2): 169-176, 2010 | DOI: 10.14411/eje.2010.022 The host recognition and acceptance behaviour of two braconid larval parasitoids (Cotesia sesamiae and C. flavipes) were studied using natural stemborer hosts (i.e., the noctuid Busseola fusca for C. sesamiae, and the crambid Chilo partellus for C. flavipes) and a non-host (the pyralid Eldana saccharina). A single larva was introduced into an arena together with a female parasitoid and the behaviour of the wasp recorded until it either stung the larva or for a maximum of 5 min if it did not sting the larva. There was a clear hierarchy of behavioural steps, which was similar for both parasitoid species. In the presence of suitable host larvae, after a latency period of 16-17 s, the wasp walked rapidly drumming the surface with its antennae until it located the larva. After location and antennal examination of the host, which lasted 60-70 s and 30 s, respectively, the parasitoid inserted its ovipositor. Stinging that resulted in successful oviposition usually lasted 5-6 s. In the presence of non-host larvae, the latency period was between 25-70 s, and parasitoids spent significantly more time walking and antennal drumming on larvae without ovipositing. It is likely that these two parasitoid species use their antennae for host recognition, and both their antennae and tarsi for final acceptance of a host for oviposition. In both C. sesamiae and C. flavipes tactile and contact-chemoreception stimuli from the hosts seemed to play a major role in the decision to oviposit. |
When landscape variables do not explain migration rates: An example from an endangered dragonfly, Leucorrhinia caudalis (Odonata: Libellulidae)Janine BOLLIGER, Daniela KELLER, Rolf HOLDEREGGEREur. J. Entomol. 108 (2): 327-330, 2011 | DOI: 10.14411/eje.2011.039 Leucorrhinia caudalis is a dragonfly species threatened throughout Europe. Despite evidence of the recent extension of its distribution range, it is unknown whether L. caudalis regularly or hardly ever migrates among ponds. The contemporary migration patterns of the species were investigated using Bayesian assignment tests and the migration rates related to landscape structural and thematic variables (distance between ponds, forest area, area of water body, area of hedgerow). Migration rates of L. caudalis are independent of any landscape element. Thus, landscape structure is not a barrier or corridor for migration in this species. The tendency of L. caudalis to disperse is largely independent of the nature of the landscape, at least at the scale of the present study. |
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. |
Life-history constraints in inaccurate Batesian myrmecomorphic spiders (Araneae: Corinnidae, Gnaphosidae)Stano PEKÁR, Martin JARABEur. J. Entomol. 108 (2): 255-260, 2011 | DOI: 10.14411/eje.2011.034 Accurate Batesian mimicry is known to impose constraints on some traits of the mimic, such as foraging or reproductive behaviour. It is not known whether life-history traits of inaccurate Batesian mimics are constrained as well. We studied selected life-history traits of three spider species, Liophrurillus flavitarsis, Phrurolithus festivus (both Corinnidae), and Micaria sociabilis (Gnaphosidae), that are inaccurate mimics of ants. Namely, we were interested in how myrmecomorphy (ant-like resemblance) constrains their circadian activity, trophic niche and reproductive behaviour. The spiders were found to have diurnal activity like their models, whereas their close relatives have nocturnal activity. The three mimics do not catch ants, nor do they use food resources of ants, but catch various tiny invertebrates that occur in the vicinity of their models. Their trophic niche seems to be constrained by occurrence among ants. Absence of courtship and long lasting copulation, in a position that does not provide protective resemblance, do not seem to be constrained by mimicry in the three species. Comparative analysis of fecundity in mimetic and non-mimetic spiders showed that clutch size is also not constrained. Unlike in accurate mimics, life-history traits of inaccurate myrmecomorphs appear not to be constrained. |
Biology of the conifer needle scale, Nuculaspis abietis (Hemiptera: Diaspididae), in northern Iran and parasitism by Aspidiotiphagus citrinus (Hymenoptera: Aphelinidae)Arash RASEKH, J.P. MICHAUD, Hassan BARIMANI VARANDIEur. J. Entomol. 108 (1): 79-85, 2011 | DOI: 10.14411/eje.2011.010 The conifer needle scale, Nuculaspis abietis (Schrank) emerged as an important pest of conifers in the Kelardasht region of Mazandaran province, Iran, in the late 1990's. This pest feeds on conifer needles and twigs causing needle drop and branch desiccation. Its discovery in Kelardasht in Mazandaran Province necessitated a local quarantine of conifers in the genera Picea, Abies, and Pinus. We studied the life history and ecology of this scale on Norway spruce, Picea abies, under laboratory and natural field conditions. The complete life cycle of females required 206.4 ± 5.7 days in the laboratory (25 ± 1°C, 65-75% RH, 14L : 10D) and 315.7 ± 9.3 days under field conditions. In Kelardasht, numbers of adult males and females peaked in mid-June and early May, respectively, and numbers of first and second instar nymphs in mid-July and early September. Lifetime fecundity was estimated to be 57.3 ± 5.1 eggs and 54.0 ± 4.4 nymphs per female under laboratory conditions. The sex ratio ranged from 59% female for second instar nymphs to 71% female for adults. Aspidiotiphagus citrinus (Crawford) (Hymenoptera: Aphelinidae) was found naturally parasitizing the scale and overwintering in the larval stage on second instar nymphs. First generation adult wasps emerged in spring from overwintered second instar nymphs to parasitize 64.75% of first instar scales. Second generation wasps emerged from early September to mid-October and parasitized 19.75% of second instar scales, for a cumulative parasitism rate of 84.5%. |
Analysis of the lipids mobilized by adipokinetic hormones in the firebug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)Iva BÁRTŮ, Aleš TOMČALA, Radomír SOCHA, Petr ŠIMEK, 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. |
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. |
Present conservation status of red wood ants in north-western Belgium: Worse than previously, but not a lost causeWouter DEKONINCK, Frederik HENDRICKX, Patrick GROOTAERT, Jean-Pierre MAELFAITEur. J. Entomol. 107 (2): 209-218, 2010 | DOI: 10.14411/eje.2010.028 The number of colonies of red wood ants (Formica rufa group) in the north western part of Belgium has declined by more than half over the past 20 years. In the study area of 20 × 50 km there are currently only 36 colonies of two species of red wood ants (Formica rufa and F. polyctena). Both species form both monodomous and polydomous colonies. Monodomous F. rufa colonies occur in large areas of open woodland dominated by Pinus sylvestris. The other three types of red wood ant (F. rufa polydomous, F. polyctena mono- and polydomous) occur in clearings or along the margins of small areas of deciduous or mixed woodland. The extinction of red wood ants cannot be attributed to a loss of their main habitat. Their decline in abundance, however, appears to be due to the deterioration in their habitat caused by several factors. Shading by overgrowing shrubs and the closure of the tree canopy, nearby intensive agriculture, urbanisation and use of the forest for recreation are the more important factors threatening and ultimately leading to the extinction of colonies. At poor quality sites there are no or very few nests of Serviformica ants, which initially serve as host ants and are necessary for recolonization by red wood ants. Thus, it is unlikely that these sites will be recolonized. To conserve red wood ants and maintain populations there is an urgent need to undertake certain measures, especially in areas outside nature reserves. For this there is a need to create clearings in the woodland, reduce shading due to overgrowing shrubs and closure of the tree canopy, and mitigate the effects of intensive agriculture, urbanisation and recreation. It is important that the effects of these measures should be monitored. |
Detection of oviposition-deterring larval tracks in Chrysopa oculata and Chrysopa perla (Neuroptera: Chrysopidae)Zdeněk RŮŽIČKAEur. J. Entomol. 107 (1): 65-72, 2010 | DOI: 10.14411/eje.2010.008 We investigated the ability of females of the aphidophagous chrysopids Chrysopa oculata and Chrysopa perla to distinguish clean substrates from substrates with tracks of chrysopid first instars after ablation of various sensory organs potentially involved in the detection of oviposition-deterring semiochemicals (ODSCs). Also studied were effects of storage time on the degree of oviposition deterrence of substrates contaminated by larvae and by extracts of ODSC in intact females. C. oculata and C. perla laid significantly fewer eggs on substrates with conspecific larval tracks than on simultaneously provided clean substrates. Females of both chrysopids could perceive ODSCs solely through sense organs on the head. The oviposition of each species was significantly lower on contaminated than on clean substrates when any kind of sense organ on the head was completely removed, i.e. antennae, maxillary palpi, or labial palpi. C. oculata could still effectively differentiate substrates after ablation of both maxillary and labial palpi, indicating possible detection of volatiles via the antennae during flight. Only if all three pairs of sensory appendages were removed did females lay similar numbers of eggs on both substrates. In contrast, C. perla laid similar numbers of eggs on clean substrates and substrates with either conspecific or C. oculata larval tracks when maxillary and labial palpi were removed. Substrates with tracks of first instars of C. perla deterred C. oculata from oviposition after one year and conspecific females after 1.5 years from contamination. Both species laid significantly fewer eggs on substrates with tracks of C. oculata first instars than on clean substrates even after three years. Tracks of C. oculata third instars did not deter conspecific females more than tracks of first instars. ODSCs from tracks were easily extracted with water. Thus, precipitation is likely to reduce deterrent effects of contaminated plants. Chloroform extract from C. oculata first instars strongly deterred conspecific females from oviposition. Even after 725 days of storage, we found no statistically significant decline in the effect. The extract could be used to redirect egg laying from constructional parts of rearing cages to exchangeable oviposition substrates in mass rearing of chrysopids used for biological control. The hexane extract of third instars was inactive. |
Differences in the sugar composition of the honeydew of polyphagous brown soft scale Coccus hesperidum (Hemiptera: Sternorrhyncha: Coccoidea) feeding on various host plantsKatarzyna GOLAN, Agnieszka NAJDAEur. J. Entomol. 108 (4): 705-709, 2011 | DOI: 10.14411/eje.2011.090 Plant chemical composition is an important determinant of host plant-insect interactions. For many insects sugars are the main factors determining the acceptability of a plant. This study investigated changes in plant chemical composition and differences in sugar composition of different host plants induced by the feeding of Coccus hesperidum L. (Hemiptera: Sternorrhyncha: Coccoidea). Present in plant extracts and honeydew there were three monosaccharide sugars: glucose, fructose and arabinose, and one disaccharide - sucrose. Arabinose was only found in extracts of Ficus benjamina plants. The sugar content of the honeydew was greater than in the extracts of control plants and lower than that in the extracts of infested plants. The honeydew collected from C. hesperidum feeding on the three plant species differed significantly in sugar content. Extracts of coccid infested plants of the three species used in this study contained more sugar than the un-infested control plants. The results show that honeydew composition of scale insects differ and the differences reflect the chemical composition of the host plants. |
Butterflies (Lepidoptera) highlight the ecological value of shrubland and grassland mosaics in Cypriot garrigue ecosystemsÖzge ÖZDEN, David J. HODGSONEur. J. Entomol. 108 (3): 431-437, 2011 We used butterfly assemblages to evaluate the ecological value of habitat mosaics within garrigue ecosystems in Cyprus. To understand the importance of the local plant communities for Cypriot butterflies, five plots in each of two habitat types (grass-dominated or shrub-dominated) were surveyed weekly for a period of five months in order to assess the abundance, species richness and diversity of butterflies. A total of 810 butterflies of 16 species were recorded. Indices of butterfly diversity, calculated across the whole season, were similar between grassland and shrubland dominated mosaics. However, species richness of all butterflies was consistently higher in grassland dominated mosaics throughout the whole season. The peak abundance of all butterfly species occurred during mid-season (late April - early May), with similar numbers observed in both habitat types. However, a greater abundance was observed during early and late season in grassland patches. The abundance of endemic species (Maniola cypricola, Hipparchia cypriensis, Glaucopsyche paphos) peaked earlier in the season in shrubland patches, but was higher in grassland patches in late season. This difference in seasonal timing of endemic abundance was dominated by the seasonal dynamics of M. cypricola. These results suggest that, while garrigue is characterised by its shrub flora, management to maintain a mosaic of grassland and shrubland could act to maximise the abundance and richness of indicator species groups of conservation importance. |
Determining the season of death from the family composition of insects infesting carrionThiago De Carvalho MORETTI, Vinícius BONATO, Wesley Augusto Conde GODOYEur. J. Entomol. 108 (2): 211-218, 2011 | DOI: 10.14411/eje.2011.029 Determining the season of death by means of the composition of the families of insects infesting carrion is rarely attempted in forensic studies and has never been statistically modelled. For this reason, a baseline-category logit model is proposed for predicting the season of death as a function of whether the area where the carcass was exposed is sunlit or shaded and of the relative abundance of particular families of carrion insects (Calliphoridae, Fanniidae, Sarcophagidae, and Formicidae). The field study was conducted using rodent carcasses (20-252 g) in an urban forest in southeastern Brazil. Four carcasses (2 in a sunlit and 2 in a shaded area) were placed simultaneously at the study site, twice during each season from August 2003 through June 2004. The feasibility of the model, measured in terms of overall accuracy, is 64 ± 14%. It is likely the proposed model will assist forensic teams in predicting the season of death in tropical ecosystems, without the need of identifying the species of specimens or the remains of carrion insects. |
Sequestration of aristolochic acids from meridic diets by larvae of Battus polydamas archidamas (Papilionidae: Troidini)Carlos F. PINTO, Alejandro URZÚA, Hermann M. NIEMEYEREur. J. Entomol. 108 (1): 41-45, 2011 | DOI: 10.14411/eje.2011.005 Larvae of the butterfly, Battus polydamas archidamas (Papilionidae: Troidini) feed exclusively on aristolochic acid (AAs)-containing Aristolochia species (Aristolochiaceae). The distribution of sequestrated AAs in the tissues (body, integument and osmeterial secretions) of B. polydamas archidamas larvae during their development, when fed on a meridic diet containing either a higher or lower concentration of AAs (AAI and AAII) than occurs naturally in the aerial tissues of their host plant, was determined. Accumulation of AAs in the body and integument was proportional to the weight of larvae and greater in the larvae that fed on the diet containing the higher concentration of AAs. Phenolic AAs (AAIa and AAIVa) not present in the diets were found in all larval tissues examined. Integument and body extracts had a higher AAI/AAII ratio than in the original diet and also a relatively high AAIa/AAIVa ratio, suggesting a preferred AAII to AAIa transformation in those larval tissues. In the osmeterial secretion, the value of the AAI/AAII ratio was similar to that in the diets and the AAIa/AAIVa ratio close to 1, which suggests that hydroxylation of AAI to AAIVa and of AAII to AAIa occur to similar extents. The higher accumulation of AAs and the relatively higher proportion of AAI, one of the most toxic AAs, in the integument, suggest that their role is to deter attacks by natural enemies. |
Identification of 18 polymorphic microsatellite loci in the spruce bark beetle Ips typographus (Coleoptera: Scolytidae) using high-throughput sequence dataBernhard C. STOECKLE, Ralph KUEHNEur. J. Entomol. 108 (1): 169-171, 2011 | DOI: 10.14411/eje.2011.021 Novel microsatellite markers for the spruce bark beetle (Ips typographus L.) are identified and characterized using next generation sequencing technology. 18 polymorphic loci were obtained by screening 10,684 reads and tested on 35 bark beetle samples from different locations in Bavaria, Germany. Allelic richness ranged from two to 38 alleles, observed heterozygosity from 0.03 to 0.66 and expected heterozygosity from 0.08 to 0.97. Four loci showed significant deviation from the Hardy-Weinberg equilibrium and no linkage between loci was detected. The 18 loci, along with another six loci previously described, provide effective analytical tools for analyzing the fine-scale genetic structure of bark beetle populations. The result of this study demonstrates that next generation sequencing technology is a valuable method for isolating microsatellites of a coleopteran species. |
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. |
Parental age at mating affects reproductive attributes of the aphidophagous ladybird beetle, Coelophora saucia (Coleoptera: Coccinellidae)OMKAR, Satyendra K. SINGH, Geetanjali MISHRAEur. J. Entomol. 107 (3): 341-347, 2010 | DOI: 10.14411/eje.2010.043 Ageing and its affect on life attributes have not been widely explored in ladybirds. The present study investigates the influence of female and male age at mating on the reproductive attributes of the ladybird beetle, Coelophora saucia (Mulsant). All reproductive attributes, viz. fecundity, percentage egg hatch, pre-oviposition, oviposition and post-oviposition periods were found to be influenced by the ages of both females and males at mating. This is unlike the results of previous studies on ladybirds, where male age was found to influence only percentage egg hatch. The influence of male age at mating on fecundity and reproductive periods is probably due to age influenced variation in seminal proteins, which influence fecundity and when the eggs are laid. |
Methoprene modifies adipokinetic hormone characteristics in the firebug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)Dalibor KODRÍK, Glenda ALQUICER, Radomír SOCHAEur. J. Entomol. 107 (1): 33-39, 2010 | DOI: 10.14411/eje.2010.003 In the present study the hypothesis that there is a feedback between juvenile hormone and adipokinetic hormones (AKHs) was investigated by topical application of the juvenoid methoprene on 9-day-old adult males of the firebug Pyrrhocoris apterus. This juvenoid (2 µg) induced a significant reduction of haemolymph lipids 24 h after treatment; however, it did not significantly reduce the ability of Pyrap-AKH (10 pmol/bug) to mobilize fat body lipids 6-72 h after the methoprene application. The same methoprene treatment elicited a significant increase of AKH content in the CNS (central nervous system: brain + corpora cardiaca + corpora allata) of experimental males 24 and 48 h after the juvenoid application. A significant decrease in the AKH level in the haemolymph was recorded at the same times and under the same experimental conditions. Similar results were observed when production of the AKHs from the CNS of topically treated males was measured under in vitro conditions. It is suggested that methoprene may reduce AKH release from the CNS resulting in an increase in the AKH content of the CNS due to accumulation rather than stimulation of AKH synthesis. Possible consequences of this phenomenon on the physiology of P. apterus are discussed. |