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Migratory flight and pre-diapause feeding of Coccinella septempunctata (Coleoptera) adults in agricultural and mountain ecosystems of Central ItalyCarlo RICCI, Luigi PONTI, Alvaro PIRESEur. J. Entomol. 102 (3): 531-538, 2005 | DOI: 10.14411/eje.2005.076 The research on pre-diapause feeding of C. septempunctata L. adults was carried out from 1998 to 2002 in the Tiber Valley, in the Botanical Garden of Perugia University, and in the Sibillini Mountains National Park (Central Italy). The species reproduces in spring feeding mostly on aphids infesting Graminaceae. In the second half of June, newly emerged adults have various migratory behaviours. Some of them remain in the valley while some leave the cereals and fly to other crops, where they feed both on 15 aphid species (e.g., Aphis gossypii Glov. on melon, Aphis fabae Scop. on sugarbeet), and also on pollens of wild plants such as Carduus nutans L., and fungi spores. However, most of the adults migrate to mountain pastures to find different food sources. During this migration, strong south-western storms often force the ladybirds to shelter in urban habitats. When the sunny weather returns again, due to the mistral (north-western wind), the adults continue the flight in swarms to mountain areas. In 1999, on Mt. Vettore (2478 m) we witnessed a "shower" of ladybirds, some of which hid in the turf. When reaching high altitude locations still covered with snow (Lake Pilato, 1940 m, on Mt. Vettore), the adults, exhausted by the long flight, usually remain motionless on the snow. Due to the warming of the sun they sink to a depth of 5-6 cm, so that they remain trapped in the frozen snow during the night. At this site C. septempunctata was found together with Vibidia duodecimguttata (Poda) and Leptinotarsa decemlineata (Say). We investigated the gut content of adults from this location. After aggregation, the hungry adults disperse to flowering plants at lower elevations where they feed on 8 aphid species (e.g. broom aphid) and pollens of several plants (e.g., Laserpitium garganicum Tem., Centaurea rupestris L., Cachrys ferulacea L. The first mating was observed on broom. At "Pian Grande" location, adults were found in crop fields (lentil, mustard) and wild pastures (cornflower, gentian) mating and feeding on aphids, pollens, nectar and fungal spores. Haymaking forces ladybirds to move towards higher locations in search of food. Echinops ritro L., Eryngium amethystinum L., Carlina acaulis L., Cirsium eriophorum (L.), Galium verum L. and Euphorbia cyparissias L. were major food sources at 1800 m altitude. Gut content of C. septempunctata adults showed that pre-diapause diet consisted of aphids, pollen of Compositae and Umbelliferae, and spores of fungi (e.g., Alternaria spp., Cladosporium spp.). There was no statistical difference between the number of adults containing remains of aphids, fungal spores, and pollens. We found four significant correlations between the different food sources observed. In August some adults stopped feeding and in diapause condition sheltered under stones and among leaves or seed capsules of plants where they had fed. Others migrated to nearby woods and aggregated between juniper needles. |
Fluctuating asymmetry as a measure of ecological stress in Drosophila melanogaster (Diptera: Drosophilidae)Vincenzo TROTTA, Federico Corrado Fulceri CALBOLI, Flavio GAROIA, Daniela GRIFONI, Sandro CAVICCHIEur. J. Entomol. 102 (2): 195-200, 2005 | DOI: 10.14411/eje.2005.031 Fluctuating asymmetry (FA), the small and random departures from perfect symmetry of an organism's bilateral traits, has been used as a measurement of developmental stability and an indicator of stress in endangered populations. We were interested in testing if the level of developmental stability is the same in different populations experiencing the same conditions, as the use of FA as an indicator of ecological stress is only meaningful if this is true. In order to do this, the effect of thermal stress on wing size FA over a range of temperatures was determined on three different lines of Drosophila melanogaster: two lines were maintained at one of two different constant temperatures (18°C or 28°C) and one under a fluctuating thermal regime (18°C and 28°C) for eight years. The differences in viability of these lines, when reared at a range of different temperatures, are associated with the temperature conditions they previously experienced. All lines showed a similar increase in FA at the two ends of the thermal range but with significantly different mean values. The two units of wing development (compartments) differed in their FA response depending on the selective history of each line. We discuss the implication of our results for the use of FA as an indicator of ecological stress. |
Ant-aphid interactions in multispecies ant communities: Some ecological and ethological aspectsTatiana A. NOVGORODOVAEur. J. Entomol. 102 (3): 495-501, 2005 | DOI: 10.14411/eje.2005.071 Investigations of the interactions between aphids and ants in multispecies ant communities and an experimental investigation of some ethological aspects of ant-aphid interactions were carried out in mixed forests at Novosibirsk Academic Centre, from 1998-2002. The eight species of ants investigated were characterized by different levels of territorial organization and interaction with aphids, which were associated with different degrees of specialization of the worker ants. The most myrmecophilous species of aphids (24 out of 33 species identified) were associated with the red wood ants. By placing Coccinella septempunctata Linnaeus (Coleoptera: Coccinellidae) in aphid colonies it was shown that only ants with large protected territories attacked the adults and larvae of the predator. Other species of ants either protected aphids only from adult ladybirds or did not guard them at all. Moreover, only individuals of Formica s. str., which has specialized workers, did not switch to collecting protein food. However, aphids make up a considerable part of the prey of ants, in which non-myrmecophilous aphids predominate (about 60-100% of the aphid prey). Moreover, ants only killed unattended or damaged myrmecophilous aphids. Formica s. str., which has the highest level of social and territorial organization, provides aphids with the most services and is the dominant species forming symbiotic relationships with aphids in the communities studied. |
Ultrastructural study of tergal and posterior sternal glands in Prorhinotermes simplex (Isoptera: Rhinotermitidae)Jan ©OBOTNÍK, Franti¹ek WEYDA, Robert HANUSEur. J. Entomol. 102 (1): 81-88, 2005 | DOI: 10.14411/eje.2005.011 In Prorhinotermes simplex, tergal glands are present on the last three tergites (from the 8th to the 10th) in imagoes of both sexes. In addition, males possess posterior sternal glands of the same structure on sternites 8 and 9. The tergal and the posterior sternal glands consist of four cell types: class 1 and class 2 secretory cells, and class 3 cells with corresponding canal cells. The cytoplasm of class 1 cells contains smooth endoplasmic reticulum, elongated mitochondria and numerous microtubules. Apical parts of these cells are formed by dense and long microvilli with a central ductule. Class 2 cells contain predominantly lucent vacuoles (in females) or lipid droplets (in males). The structure of class 3 cells does not differ from class 3 cells found in other body parts. |
Cold hardiness in Ostrinia nubilalis (Lepidoptera: Pyralidae): Glycerol content, hexose monophosphate shunt activity, and antioxidative defense systemBojana STANIC, Aleksandra JOVANOVIC-GALOVIC, Dusko P. BLAGOJEVIC, Gordana GRUBOR-LAJSIC, Roger WORLAND, Mihajlo B. SPASICEur. J. Entomol. 101 (3): 459-466, 2004 | DOI: 10.14411/eje.2004.065 Many insects in temperate regions overwinter in diapause, during which they are cold hardy. In these insects, one of the metabolic adaptations to the unfavorable environmental conditions is the synthesis of cryoprotectants/anhydroprotectants. The aim of this study was to investigate the connection between the antioxidative system and synthesis of cryoprotectants (mainly glycerol) in diapausing larvae of the European corn borer, Ostrinia nubilalis (Lepidoptera: Pyralidae). At two periods during diapause (November and February), in three groups of insects (kept under field conditions; -12°C for two weeks; 8°C for two weeks), the activity of key enzymes of the antioxidative system and oxidative part of the hexose monophosphate shunt were measured: superoxide dismutase, catalase, non selenium glutathione peroxidase, glutathione S-transferase, glutathione reductase, glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, as well that of the antioxidative components: total glutathione and ascorbate, and dehydroascorbate reductase. There was a higher activity of antioxidative enzymes at the beginning of the diapause period (November) compared to late diapause (February), while glutathione and ascorbate were higher in February. Similarly, there was a lower activity of the hexose monophosphate shunt enzymes in February. Exposure of larvae to -12°C resulted in an elevation of hexose monophosphate shunt enzyme activity, especially in November. This was accompanied by a significant increase in glycerol content in February. Changes in ascorbate levels and dehydroascorbate reductase activity in both experimental groups (-12°C and 8°C) suggest a connection between the antioxidative system, metabolism during diapause and cold hardiness. Our results support the notion that antioxidative defense in larvae of Ostrinia nubilalis is closely connected with metabolic changes characteristic of diapause, mechanisms of cold hardiness involved in diapause and the maintenance of a stable redox state. |
Immature stages of New Caledonian Tingidae (Heteroptera): Description and developmentEric GUILBERTEur. J. Entomol. 101 (2): 261-271, 2004 Second to fifth instars of nine New Caledonian species of Tingidae are described. A key to fifth instars is provided. The comparison of immature stages among the known larvae shows that translocation of marginal tubercles in larvae, considered as the general rule, is absent in New Caledonian larvae. Also, external morphology of larvae becomes more complex through development, by the addition and ramification of tubercles, as it does also through evolution. Such a tendency is reminiscent of a heterochronous phenomenon, like peramorphosis. Translocation phenomenon could be an intermediate stage of evolution in terms of aquiring more tubercles. |
Fluctuating asymmetry, body size, reproductive period and life time mating success of males of Cercion lindeni (Odonata: Coenagrionidae)Gianmaria CARCHINI, Marco Di DOMENICO, Flavia CHIAROTTI, Carla TANZILLI, Tiziana PACIONEEur. J. Entomol. 102 (4): 707-712, 2005 Mating success is linked to reproductive success in males, but parameters influencing it are poorly known. The relationships between lifetime mating success (LMS), fluctuating asymmetry (FA), body size (SIZE), reproductive period (RP) and emergence date (MD) of males of Cercion lindeni were investigated. Males were marked and photographed in their pre-reproductive period, and their matings monitored. RP was assumed to be the period between the MD and the last sighting of each individual. Three different FA measures and the size of each individual were determined. The results showed that the individuals not present at the pond during the reproductive period had a higher FA (but not for meristic characters) than those present. For those individuals actually involved in reproductive activity, LMS was only positively correlated with RP, which was negatively related with MD, and this with SIZE. |
Molecular phylogeny of the Aphidiinae (Hymenoptera: Braconidae) based on DNA sequences of 16S rRNA, 18S rDNA and ATPase 6 genesMin SHI, Xue-Xin CHENEur. J. Entomol. 102 (2): 133-138, 2005 | DOI: 10.14411/eje.2005.021 Phylogenetic relationships among 16 genera of the subfamily Aphidiinae (Hymenoptera: Braconidae) were investigated using sequence data from three genes: the mitochondrial large ribosomal subunit (16S), 18S ribosomal DNA and mitochondrial ATPase 6. All sequences were downloaded from the GenBank database. A total of 2775 base pairs of aligned sequence were obtained per species from these three genes. The results support the existence of three-tribes: Ephedrini, Praini and Aphidiini, with the Ephedrini occupying the basal position; Aphidiini could be further subdivided into three subtribes: Monoctonina, Trioxina and Aphidiina. The genus Aphidius is a paraphyletic group. The taxonomic status of the subfamily Aphidiinae within the Braconidae is probably closer to the non-cyclostome than the cyclostome subfamilies. |
Supercooling capacity and cold hardiness of the eggs of the grasshopper Chorthippus fallax (Orthoptera: Acrididae)Shu-Guang HAO, Le KANGEur. J. Entomol. 101 (2): 231-236, 2004 Cold tolerance of the eggs of the grasshopper, Chorthippus fallax (Zubovsky), was examined in the laboratory. Egg supercooling points varied from -6°C to -32.4°C and could be divided into two groups. The supercooling points of the higher SCP group ranged from -6°C to -14°C and those of lower SCP group from -21.8°C to -32.4°C. Although low temperature acclimation could slightly decrease the supercooling points of eggs, the effect was not significant for all embryonic developmental stages or acclimation periods. The supercooling capacity was obviously different between pre-diapause, diapause and post-diapause embryonic stages. The mean supercooling points of pre-diapause and diapause eggs were similar; -28.8 ± 1.6°C and -30.7 ± 1.0°C for non-acclimated eggs and -29.5 ± 1.3°C and -31.18 ± 0.8°C for acclimated eggs respectively. However, the mean supercooling points of post-diapause eggs were significantly higher; -12.9 ± 5.6°C for non-acclimated and -13.5 ± 4.5°C for acclimated eggs respectively. The survival rates of diapause eggs at > -25°C were not significantly different from that at 25°C, but survival rates at < -30°C decreased significantly. The lethal temperature (Ltemp50) for a 12 hrs exposure was -30.1°C, and the lethal time (Ltime50) at -25°C was 44 days. Since the SCPs of diapause eggs was similar to their Ltemp50, we may consider the supercooling capacity of such eggs is a good indicator of their cold hardiness and the species is a true freeze avoiding insect. Based on the analysis of local winter temperature data, pre-diapause and diapause, low SCP eggs can safely survive severe winters, but not the post-diapause, high SCP eggs. The importance of the overwintering strategy and the relationship between diapause and cold hardiness of this species is discussed. |
Comparison of the suitability of three pest leafminers (Diptera: Agromyzidae) as hosts for the parasitoid Dacnusa sibirica (Hymenoptera: Braconidae)Yoshihisa ABE, Tomohiko TAKEUCHI, Susumu TOKUMARU, Jun KAMATAEur. J. Entomol. 102 (4): 805-807, 2005 The suitability of Liriomyza sativae Blanchard, L. trifolii (Burgess) and L. bryoniae (Kaltenbach) as hosts of the solitary larval-pupal parasitoid Dacnusa sibirica Telenga was studied. This parasitoid is used as a biological control agent against L. trifolii and L. bryoniae. The parasitoid laid eggs in L. sativae, but no adult parasitoids emerged from the puparia. In contrast, D. sibirica adults emerged from the puparia of L. trifolii and L. bryoniae, and there was no significant difference in emergence rate, female developmental time, or sex ratio when parasitizing these two host species. The parasitoid adults that emerged from the L. bryoniae puparia were significantly larger than those from L. trifolii puparia. In conclusion, D. sibirica, a useful biological control agent of L. trifolii and L. bryoniae, cannot control L. sativae. |
Role of (E)-β-farnesene in systematic aphid prey location by Episyrphus balteatus larvae (Diptera: Syrphidae)Frédéric FRANCIS, Thibaut MARTIN, Georges LOGNAY, Eric HAUBRUGEEur. J. Entomol. 102 (3): 431-436, 2005 | DOI: 10.14411/eje.2005.061 The foraging behaviour of beneficials such as aphidophagous predators depend largely on volatile compounds emitted by potential preys. Even if polyphagous predatory species are considered, all the potential preys are not systematically localised and accepted. In this work, chemical cues from different aphids and plants, each alone or in association, were studied to elucidate their role in prey location. Using a four-arm olfactometer, attraction of combinations of three aphid (Megoura viciae, Acyrthosiphon pisum and Aphis fabae) and one plant (Vicia faba) species for Episyrphus balteatus larvae was observed. Predatory hoverfly larvae were attracted by all tested stimuli in the presence of aphids, whatever the species. Whole or crushed aphids and also aphids on bean plant parts were attractive to syrphid larvae, but the host plant alone did not present any infochemical role for E. balteatus. Identification and quantification of the volatile releases from aphid and plant species, alone or in association, were performed using SPME and GC-MS methods. Aphid alarm pheromone, (E)-β-farnesene, was found in the volatile pattern of each aphid and was tested for its role as an effective kairomone for the hoverfly. |
Coprophagous hydrophilid beetles (Coleoptera: Hydrophilidae) as carriers of phoretic deutonymphs of Uropoda orbicularis (Acari: Mesostigmata) in PolandDaria BAJERLEIN, Marek PRZEWO¬NYEur. J. Entomol. 102 (1): 119-122, 2005 | DOI: 10.14411/eje.2005.017 During a study 20 hydrophilid beetle species and 2,457 individuals of beetles belonging to 4 genera: Cercyon, Cryptopleurum, Megasternum and Sphaeridium were collected. On the surface of the bodies of 59 beetles (2.40% of the beetles collected) belonging to six species, 174 cases of phoresy [55 deutonymphs of Uropoda orbicularis (Müller, 1776) and 119 pedicels without deutonymphs] were observed. New hydrophilid beetle carriers of phoretic deutonymphs of U. orbicularis are given. Most mites were carried by Sphaeridium species. The population dynamics of both groups of arthropods was also studied. Most cases of phoresy were recorded in May and in the second half of July. However, phoretic deutonymphs were not present on the body surface of hydrophilid beetles throughout the whole period of this study. |
Seasonality, abundance, species richness and specificity of the phytophagous guild of insects on oak (Quercus) canopiesT. Richard E. SOUTHWOOD, G.R. William WINT, Catherine E.J. KENNEDY, Steve R. GREENWOODEur. J. Entomol. 101 (1): 43-50, 2004 | DOI: 10.14411/eje.2004.011 1. A study was made by knockdown sampling and branch clipping of the arthropod fauna of two native oaks (Quercus petraea and Q. robur) and of two introduced species (Q. cerris and Q. ilex) in woods near Oxford, U.K., and of two native species (Q. ilex and Q. pubescens) in southern France. Sampling was undertaken for five years in England and four years in France. All the phytophagous species except Acarina and Cecidomyidae from the Oxford samples were identified to species. |
Homology and morphology in Poduromorpha (Hexapoda, Collembola)Cyrille A. D'HAESEEur. J. Entomol. 100 (3): 385-407, 2003 | DOI: 10.14411/eje.2003.060 The detailed external morphology and general anatomy of the majority of families and subfamilies of Poduromorpha were investigated and compared. This examination was done in relation to the three remaining orders of Collembola: Entomobryomorpha, Symphypleona and Neelipleona. Within Poduromorpha, homologies among the different families and subfamilies are established for general chaetotaxy, and chaeotaxy of head, buccal cone, sensilla of fourth antennal segment, anal valves and tibiotarsus. A consistent and comprehensive nomenclature is proposed for these morphological features unifying those applied in scattered existing studies. Observations on first instars are reported. Comparison of first instars and adult chaetotaxy suggests a possible paedomorphic trend in the evolution of Poduromorpha. |
Systemic effects of phytoecdysteroids on the cabbage aphid Brevicoryne brassicae (Sternorrhyncha: Aphididae)Roman PAVELA, Juraj HARMATHA, Martin BÁRNET, Karel VOKÁÈEur. J. Entomol. 102 (4): 647-653, 2005 The systemic effects of phytoecdysteroids were investigated by applying tested compounds to the roots of the rape plants. Evaluation of the effects was based on mortality, longevity, rate of development and fecundity of the cabbage aphid (Brevicoryne brassicae L., Sternorrhyncha: Aphididae) feeding on the shoot of the treated plants. The major ecdysteroid compounds tested were natural products isolated from a medicinal plant Leuzea carthamoides DC (Willd.) Iljin (Asteraceae): 20-hydroxyecdysone (20E), ajugasterone C (ajuC) and polypodine B (polyB). The compounds were tested in two concentrations (0.07 and 0.007 mg/ml) in water. In addition, we have also investigated the systemic effects of a special Lc-Ecdy 8 fraction isolated from L. carthamoides, which contained 20E, ajuC and polyB and at least six other minor compounds in addition to the above indicated ecdysteroids. HPLC analysis of the Lc-Ecdy 8 fraction indicated the presence of makisterone A and inokosterone in minor quantities. It appeared that all ecdysteroid compounds tested, with the exception of the most common, 20E, decreased the fecundity of cabbage aphids which fed on the contaminated rape plants. The mortality of larvae and adults significantly increased on plants treated with the Lc-Ecdy 8 fraction, and with ajuC or polyB compounds containing structural substituents in rather unusual positions. The most common phytoecdysteroid, 20E, with the typical and characteristic ecdysteroid structure, was the best tolerated of all phytoecdysteroids tested. |
Characterisation of the luciferase gene and the 5' upstream region in the European glow-worm Lampyris noctiluca (Coleoptera: Lampyridae)John C. DAYEur. J. Entomol. 102 (4): 787-791, 2005 Beetle luciferase, a mono-oxygenase within the AMP-binding superfamily, is synthesized by bioluminescent beetles in concentrated levels within specialised cells clustering in the abdominal light organs. In vivo expression of luciferase has been rarely investigated and little is known about the role of enhancers and promoters in the expression of this gene. In order to investigate the gene structure and potential control of gene expression the luciferase gene along with 6 kb of upstream genomic sequence was characterised from the European glow-worm Lampyris noctiluca. Three TATA box motifs and a CAAT repeat were identified, two of these were found to be conserved in two other species of bioluminescent beetle. Although no enhancer regions were identified in the upstream sequence a region coding for a putative transposase DDE domain was identified 686 bp from the start codon of the luciferase gene. Although disrupted, the open reading frame also shared extensive identity to an mRNA transcript from the mosquito Anopheles gambiae. The remnants of an ancient transposase provide support for an ancestral luciferase transposition/insertion event that may have occurred within the genome of bioluminescent beetles. |
Time of oviposition and reproductive success in Argiope bruennichi (Araneae: Araneidae)Raymond LEBORGNE, Alain PASQUETEur. J. Entomol. 102 (2): 169-174, 2005 | DOI: 10.14411/eje.2005.027 Time of oviposition and investment in reproduction output are a crucial decision for animals which could affect their fitness. In this study, the factors determining the time of oviposition and the consequences it has for clutch size and juvenile survival were investigated in the orb-web spider Argiope bruennichi. Egg-sacs laid at different times in the field were collected and inspected for eggs, hatching success and presence of parasites. Relationships between spider body condition, clutch size and time of oviposition were established. The influence of supplementary food on the number of eggs in a clutch and on the time of oviposition was determined both in the field and laboratory. Early clutches were larger and the eggs in late clutches were not heavier than those in early clutches indicating that spiders invested more in eggs at the beginning of the reproductive period. Furthermore, eggs in late egg-sacs were less likely to hatch and more likely to be parasitized. Clutch size was linked to spider body condition but not the time of oviposition. In the field, additional food to females resulted in larger clutches but did not influence the time of oviposition. Laboratory experiments showed that the daily rate of prey consumption affected egg oviposition. |
Geographical distribution of three oceanic Halobates spp. and an account of the behaviour of H. sericeus (Heteroptera: Gerridae)Tetsuo HARADAEur. J. Entomol. 102 (2): 299-302, 2005 | DOI: 10.14411/eje.2005.043 Halobates spp. are the only insects inhabiting the open sea. One sea skater species, Halobates sericeus, was collected at 18 locations in the East China Sea area (27°10´N- 33°24´N, 124°57´E-129°30´E), and H. micans and/or H. germanus at only 8 locations in the area south of 29°47´N, where water temperatures were more than 25°C. At three locations, where the water temperature was less than 23°C, neither H. micans nor H. germanus were caught. The effect of photoperiod on the aggregation and mating behaviour of the sea skater, H. sericeus, was studied under laboratory conditions during a one-month cruise. Adults and 5th instar larvae of H. sericeus, collected between 29°02´N and 30°29´N, were kept under long (14.5L : 9.5D) or short-day (10.5L : 13.5D) conditions at 23 ± 2°C for 20 days. Aggregation and mating behaviour of these sea skaters were recorded over a period of 150 min during the daytime. To analyze the data, the observation period of 150 min was divided into 50 intervals of 3 min. Aggregation was observed more under short than long-days. Duration of a group was much longer under the short (mean ± SD : 43.0 ± 108.1 sec) than long-days (7.6 ± 3.1 sec). |
Structure of the cuticle of some ptyctimine oribatids (Acari: Oribatida)Jaroslav SMR®Eur. J. Entomol. 102 (1): 89-95, 2005 | DOI: 10.14411/eje.2005.012 Abstract. The cuticle of Rhysotritia duplicita (Euphtiracaroidea: Euphtiracaridae), Phthiracarus sp., Steganacarus magnus, S. striculus and Tropacarus carinatus (all Phthiracaroidea: Phthiracaridae) was studied by light and transmission electron microscopy. A combination of light and electron microscopy were used to precisely characterize and classify the cuticular layers in oribatid mites and show how they differe in mites and other arthropods. In Rhysotritia duplicata the cuticle of the aspis (upper shield of the prosoma) differs significantly from that of the opisthosoma. Moreover, prosomal cuticle in this species is different from that of all others species studied. There were no structural differences in the cuticle of the prosoma and opisthosoma of species of the superfamily Phthiracaroidea (Phthiracarus, Steganacarus and Tropacarus) in spite of the differences in external apparence. Moreover, in Tropacarus, the rough sculpturing of the cuticle results from the very rough exocuticle, which is unlike the thick smooth cerotegument of the cuticle in Steganacarus. |
Using internally transcribed spacer 2 sequences to re-examine the taxonomic status of several cryptic species of Trichogramma (Hymenoptera: Trichogrammatidae)Zheng-Xi LI, Li ZHENG, Zuo-Rui SHENEur. J. Entomol. 101 (3): 347-358, 2004 | DOI: 10.14411/eje.2004.049 Mass releases of Trichogramma confusum Viggiani and T. maidis Pintureau & Voegele are widely used to control lepidopterous pests. They have long been considered to be the subspecies of T. chilonis Ishii and T. brassicae Bezdenko, respectively. To re-examine the taxonomic status of these closely related Trichogramma species, the internally transcribed spacer 2 (ITS2) of ribosomal DNA was used as a molecular marker to detect between-species differences. The ITS2 regions of 7 different Trichogramma species collected from China, Germany and France were sequenced and the inter-species distances were calculated. To quantify within-species sequence variation, the ITS2 regions of 6 geographical populations of T. dendrolimi Matsumura collected from across China were sequenced and compared. The results show that the ITS2 sequences of T. confusum and T. maidis are sufficiently different from those of T. chilonis and T. brassicae, respectively, that it is difficult to group them as cryptic species, whereas there are only minor differences between the T. dendrolimi populations. The ITS2 sequences identified in this study, coupled with 67 ITS2 sequences from a wide geographical distribution retrieved from GenBank, were then used for phylogenetic analyses. The results support previous records of minor within-species ITS2 sequence divergence and distinct interspecies differences. The cladograms show the T. maidis sequence clustered within T. evanescens Westwood, while the ITS2 sequences of T. confusum and T. chilonis are clustered in different branches. Taken together, these data suggest that T. maidis is not T. brassicae, but a cryptic or sibling species of T. evanescens; T. confusum and T. chilonis are not cryptic species but two closely related sister species. |
Phoresy of Uropoda orbicularis (Acari: Mesostigmata) by beetles (Coleoptera) associated with cattle dung in PolandDaria BAJERLEIN, Jerzy BUOSZYKEur. J. Entomol. 101 (1): 185-188, 2004 | DOI: 10.14411/eje.2004.022 Of 31 species of coprophagous beetles from the following families: Aphodiidae, Geotrupidae, Scarabaeidae, individuals of 25 species carried deutonymphs of Uropoda orbicularis (Müller, 1776). The mite's preferences for attaching to specific parts of an insect's body were determined by examining 4,318 specimens of beetles from the following families: Aphodiidae, Geotrupidae, Scarabaeidae, Hydrophilidae and Histeridae. We recorded 14,507 cases of phoresy (5,822 deutonymphs and 8,685 of pedicels without mites) on 2,056 insects. Elytra and the third pair of legs were the areas most frequently occupied by the mites. The mite's preferences for attaching to specific parts of an insect body are reported for the first time. |
Habitat factors influencing the presence of adult Calopteryx splendens (Odonata: Zygoptera)Louise WARD, Peter J. MILLEur. J. Entomol. 102 (1): 47-51, 2005 | DOI: 10.14411/eje.2005.007 1. In Great Britain the distribution of the riverine damselfly Calopteryx splendens is predominantly southern. However, the last decade has seen records of the species in previously unoccupied areas in the northeast of England, prompting speculation regarding northward range expansion. The current study is the first to quantify the physical features of the habitat that influence the presence of C. splendens. |
Genomic structure and phylogenetic analysis of the luciferase gene of the firefly, Luciola lateralis (Coleoptera: Lampyridae)Jong Gill KIM, Yong Soo CHOI, Keun Young KIM, Jin Sik BAE, Iksoo KIM, Hung Dae SOHN, Byung Rae JINEur. J. Entomol. 101 (1): 1-11, 2004 | DOI: 10.14411/eje.2004.001 The complete nucleotide sequence and the exon-intron structure of the luciferase gene of the firefly, Luciola lateralis (Coleoptera: Lampyridae) is described. The luciferase gene of the L. lateralis firefly spans 1,971 bp and consists of six introns and seven exons coding for 548 amino acid residues. From samples collected at Boun and Muju, Korea, three isoforms, with identical exon-intron structure, named BU, MJ1 and MJ2, respectively, were obtained. Although the amino acid sequences of MJ1 and MJ2 were identical to those of known luciferase genes of Korean origin, the BU type was novel, differing from each of the MJ1 and MJ2 types by one amino acid. The luciferase sequences of the Korean samples, including those previously revealed, differed only by one - two amino acid residues, but differed by five - six amino acid residues from that of the luciferase gene recorded from specimens from Japan, which suggest genetic divergence has occurred in this species. Phylogenetic analyses using both amino acid and nucleotide sequences further showed that the luciferase gene of the Japanese L. lateralis firefly is genetically distinguishable from that of Korean L. lateralis, suggesting the presence of a genetic subdivision between the L. lateralis dwelling in the Korean Peninsula and Japanese Islands. |
Gene cloning and sequencing of aminopeptidase N3, a putative receptor for Bacillus thuringiensis insecticidal Cry1Ac toxin in Helicoverpa armigera (Lepidoptera: Noctuidae)Gui-Rong WANG, Ge-Mei LIANG, Kong-Ming WU, Yu-Yuan GUOEur. J. Entomol. 102 (1): 13-19, 2005 | DOI: 10.14411/eje.2005.002 A cDNA encoding aminopeptidase N3 was cloned by degenerated PCR and RACE techniques. The full-length of APN3harm is 3486bp. Open reading frame is 3042bp in length, encoding 1014 amino acid residues. Its predicted molecular weight and isoelectric point are 117.04 kDa and 5.14, respectively. This deduced amino acid sequence shares some common structural features with aminopeptidase N from Lepidoptera, including the consensus zinc-binding motif HEXXHX18E and the GAMEN motif common to gluzincin aminopeptidases. The full-length of the APN3harm gene from three susceptible and three resistant strains were cloned and sequenced. Comparison analysis revealed fourteen amino acid differences in the APN3harm gene from resistant and susceptible strains and six mutations of amino acids exist in all resistant strains. It is possible that these mutations are related to the resistance of Helicoverpa armigera to Cry1Ac toxin. The results of semi-quantitative RT-PCR showed that the resistance of H. armigera to Cry1Ac is unrelated to the amount of APN3harm mRNA in midgut tissue. In susceptible strains, APN3harm is highly expressed in mid-gut, foregut and hindgut but not in other tissues. To determine if the APN3harm is the receptor of Cry1Ac, recombinant APN3harm protein was successfully expressed in E. coli. A ligand binding experiment showed purified product could bind Cry1Ac toxin. So it is proposed that APN3harm is a putative receptor of Cry1Ac in H. armigera. The sequence of APN3harm was deposited in GenBank with the accession number AY052651. |
Kin recognition and avoidance of kin cannibalism by the larvae of co-occurring ladybirds: a laboratory studyAhmad PERVEZ, Avanish K. GUPTA, OMKAREur. J. Entomol. 102 (3): 513-518, 2005 | DOI: 10.14411/eje.2005.073 The role of relatedness and diet in kin recognition was investigated in the aphidophagous ladybirds Propylea dissecta and Coccinella transversalis. Third instar larvae of both species exhibited kin recognition, as they were reluctant to consume related first instar larvae. They spent significantly more time prior to cannibalism when interacting with genetically related victims; this indicates the presence of a kin recognition system. Kin recognition, however, was not evident in fourth instar larvae as they ate both related and unrelated victims. This result reveals that the need of fourth instar larvae to attain a critical weight for pupation might subdue kin recognition. The diet of cannibals did not affect cannibalism, number of encounters or time that elapsed prior to cannibalism. This indicates that kin recognition is not dependent on exogenous cues derived from the diets of the cannibal and victim. |
Indirect effects of ant predation (Hymenoptera: Formicidae) on bilberry Vaccinium myrtillusOla ATLEGRIMEur. J. Entomol. 102 (2): 175-180, 2005 | DOI: 10.14411/eje.2005.028 Bilberry (Vaccinium myrtillus L.) is one of the dominant plants of the Fennoscandian boreal coniferous forest and constitutes a major food source for many insect herbivores. A common ant species in these forests is the wood ant Formica (Formica) aquilonia Yarrow, which preys heavily on other invertebrates within its territories. The aim of this study was to investigate whether aquilonia's predation on the insect herbivores may have indirect positive or negative effects on bilberry. Damage to the bilberry, its vegetative growth and reproduction were quantified in order to contrast localities close to (2 m) and far away from (50 m) ant nests. |
Review of larval morphology of beetles of the suborder Archostemata (Insecta: Coleoptera), including first-instar chaetotaxyVasily V. GREBENNIKOVEur. J. Entomol. 101 (2): 273-292, 2004 This paper presents a synthesis of morphological information on larvae of the beetle suborder Archostemata. Larvae of the following families and species were studied: Ommatidae: Omma sp.; Micromalthidae: Micromalthus debilis LeConte, 1878; Cupedidae: Priacma serrata LeConte, 1861, Distocupes varians (Lea, 1902), Rhipsideigma raffrayi (Fairmaire, 1884), Tenomerga cinerea (Say, 1831) and Tenomerga mucida (Chevrolat, 1829). Morphological characters of the suborder and three families are described. Monophyly of the suborder is strongly supported by more than 10 larval autapomorphies. A close relationship between Micromalthidae and Cupedidae is confirmed. New larval characters are introduced, including chaetotaxy of first instar larvae of Micromalthus LeConte, 1878, Priacma LeConte, 1874 and Distocupes Neboiss, 1984. An identification key to families and subfamilies of Archostematan larvae is provided, along with a checklist of extant Archostemata taxa. The work is illustrated with 120 morphological drawings. |
Trypsin-like activity of membrane-bound midgut proteases from Anticarsia gemmatalis (Lepidoptera: Noctuidae)Luciana Pereira XAVIER, Maria Goreti ALMEIDA OLIVEIRA, Raul Narciso Carvalho GUEDES, Agenor Valarades SANTOS, Salvatore Giovanni DE SIMONEEur. J. Entomol. 102 (2): 147-153, 2005 | DOI: 10.14411/eje.2005.023 Membrane-bound proteases from preparations of the midgut of 5th instar velvetbean caterpillars, Anticarsia gemmatalis (Hübner) were obtained by resuspension of the pellet obtained after 100,000 g centrifugation. As expected of trypsin-like proteases, they hydrolyzed casein and the synthetic substrates N-α-benzoyl-L-Arg-p-nitroanilidine (L-BApNA) and N-α-p-tosyl-L-Arg methyl ester (L-TAME). Higher activities were observed at 50°C, and at pH 8.5 and 8.0 for both synthetic substrates L-BApNA and L-TAME. The membrane-bound proteases were inhibited by EDTA, phenylmethan sulphonyl fluoride (PMSF), tosyl-L-lysine chloromethyl ketone (TLCK), benzamidine and aprotinin. TLCK and benzamidine were particularly active inhibitors. The KM-values obtained were 0.23 mM for L-BApNA and 92.5 µM for L-TAME. These results provide evidence for the presence of membrane-bound trypsin-like proteases in the midgut of the velvetbean caterpillar, a key soybean pest in warm climates. The interaction between A. gemmatalis digestive proteases and soybean protease inhibitors has potentially important consequences for soybean breeding programs. |
Effects of parasitoid associated factors of the endoparasitoid Glyptapanteles liparidis (Hymenoptera: Braconidae)Nicole A. TILLINGER, Gernot HOCH, Axel SCHOPFEur. J. Entomol. 101 (2): 243-249, 2004 The endoparasitoid Glyptapanteles liparidis (Hymenoptera: Braconidae) injects polydnavirus and venom together with eggs into its Lymantria dispar (Lepidoptera: Lymantriidae) host larvae during oviposition. We studied effects of these parasitoid associated factors by means of g-irradiation-induced pseudoparasitization. The application of radiation for sterilization of female wasps as a tool to study interactions between parasitoid associated factors and the host is demonstrated in this paper. When wasps were irradiated at doses ranging from 24 to 96 Gy and then allowed to oviposit into L. dispar larvae, temporary sterilization was produced. On the first day post irradiation they laid 99% sterile eggs, but fertility recovered partially during the following days. Irradiation had no negative effect on the lifespan of wasps, but total fecundity was significantly reduced. Pseudoparasitization of L. dispar by irradiated G. liparidis caused prolonged larval development with supernumerary molts before pupation in females, and higher pupal weights in both sexes. Only 8 to 20% of pseudoparasitized larvae developed into adults; 20 to 33% died as larvae, 55 to 65% in pupae. Abnormities, such as precocious formation of pupal antennal pads in larvae or incomplete sclerotization of pupal cuticle occurred. Pseudoparasitization impaired the immune reactions of L. dispar larvae. Encapsulation of implanted plastic rods by hemocytes was reduced and hemolymph melanization was significantly suppressed 3 and 5 days post pseudoparasitization. |
The impact of individual ladybirds (Coccinella septempunctata, Coleoptera: Coccinellidae) on aphid coloniesNicole MINORETTI, Wolfgang W. WEISSEREur. J. Entomol. 97 (4): 475-479, 2000 | DOI: 10.14411/eje.2000.073 Pea aphids (Acyrthosiphon pisum) have been reported to produce winged offspring in the presence of predatory ladybirds. These offspring may leave host plants by flight after they have developed into winged adults. The inter-generational nature of this response raises the question about the chances of survival of aphids developing in attacked colonies. We studied the behaviour of predatory ladybirds on host plants by releasing adult 7-spot ladybirds (Coccinella septempunctata) on bean plants hosting either no prey individuals or colonies of 10 or 30 pea aphids. Interactions between predator and prey were recorded until the ladybird left the plant. Ladybird patch residence time increased with the number of aphids present on a plant but beetles generally left a plant before all aphids were eaten. The time budget of the ladybirds revealed a high proportion of time not spent in feeding activities. Predation rate was about one aphid killed per 10min residence time in both treatments with aphid-infested plants. Aphids that survived an attack by the predator or that were alarmed when a conspecific was attacked often emigrated from the host plant, and their number was of the same magnitude as the number of aphids killed by the predator. On average, pea aphid numbers at the end of an experiment were reduced to less than a third of the initial value. The results of the experiment show that attack by single ladybirds does on average not cause immediate extinction of small aphid colonies. The short patch residence times of on average less than two hours show that a predator individual that induces winged-offspring production in an aphid colony will not any longer be present in the colony when the induced offspring mature. To understand the adaptiveness of predator-induced wing development in pea aphids the probabilities of subsequent attacks on an aphid colony need to be investigated. |