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Effect of larval crowding on the life history traits of Sesamia nonagrioides (Lepidoptera: Noctuidae)Argyro A. FANTINOU, Dionyssios C. PERDIKIS, Nikolaos STAMOGIANNISEur. J. Entomol. 105 (4): 625-630, 2008 This study determined the effect of larval density-dependent competition for food on development and adult fitness in Sesamia nonagriodes Lef. (Lepidoptera: Noctuidae). Different numbers (5, 10, 15, 20 and 30 individuals) of larvae of the pink stalk borer were reared on a constant amount of food. Although crowding during the immature stages did not significantly increase mortality, it prolonged the larval developmental period and resulted in reduced pupal weight. Females were more adversely affected by high density than males, resulting in lighter females, indicating that female growth is more sensitive to density. The fecundity of the adults reared in the various larval crowding treatments was analysed. Total female fecundity was correlated negatively with increasing larval density. The effects of crowding on fecundity were not caused by the reduced pupal weight, indicating that food shortage during larval development may affect adult traits. Female longevity was negatively affected by density and positively related to pupal weight. Thus, larval density may affect the allocation of food resources and adult fitness. We conclude that crowding related changes during larval development directly affect larval life and reduce female fitness. |
Morphology, taxonomy and distribution of Diphyonyx gen. n., a lineage of geophilid centipedes with unusually shaped claws (Chilopoda: Geophilidae)Lucio BONATO, Marzio ZAPPAROLI, Alessandro MINELLIEur. J. Entomol. 105 (2): 343-354, 2008 | DOI: 10.14411/eje.2008.041 A new genus Diphyonyx is proposed here for a previously unrecognised lineage of geophilid centipedes. It is distinct from other geophilids in its unique combination of morphological characters, including the peculiar shape of the pretarsus of the legs on the anterior part of the trunk. The type species D. conjungens (Verhoeff, 1898), comb. n., is redescribed in detail and its geographical distribution updated (Balkan Peninsula, Anatolia, Crimea). Included in Diphyonyx are also D. sukacevi (Folkmanová, 1956), comb. n., and D. garutti (Folkmanová & Dobroruka, 1960), comb. n., both from southern Russia. D. garutti is raised here to species rank. |
On the systematic position of the diving-beetle genus Pachydrus (Coleoptera: Dytiscidae: Hydroporinae): Evidence from larval chaetotaxy and morphologyMariano C. MICHAT, Patricia L.M. TORRESEur. J. Entomol. 105 (4): 737-750, 2008 Phylogenetic relationships within the diving-beetle subfamily Hydroporinae are not well understood. Some authors include the genus Pachydrus Sharp, 1882 in the tribe Hyphydrini, whereas others are in favour of excluding Pachydrus from the Hyphydrini and placing it in its own tribe, Pachydrini. Larval characters have been underutilised in phylogenetic studies, mainly because the larvae of many taxa within the family are unknown. In this study, the phylogenetic relationships of Pachydrus are studied based on a cladistic analysis of 34 taxa and 122 morphological larval characters. For this purpose, larvae of P. obesus Sharp, 1882 are described and illustrated in detail for the first time, with particular emphasis on morphometry and chaetotaxy. First and second instars for the genus were unknown. The results support a monophyletic origin of the tribe Hyphydrini excluding Pachydrus, based on four unique character states. On the other hand, Pachydrus is resolved as the sister group of the Hydrovatini. These results suggest Pachydrus should not be placed in the Hyphydrini. Given that the Hyphydrini minus Pachydrus is a distinctive clade, based on this study, it seems useful to recognise this group as Hyphydrini. Including Pachydrus in Hyphydrini would leave the tribe with a single larval apomorphy, as most characters present in the Hyphydrini and Pachydrus are also present in the Hydrovatini. However, in the absence of larvae of Heterhydrus Fairmaire, 1869 and of a more comprehensive and inclusive analysis, we do not propose a formal exclusion of Pachydrus from Hyphydrini at this stage. Pachydrus is a highly distinctive genus within the Hydroporinae and is characterised by several larval apomorphies. |
Intronic sequences of the silkworm strains of Bombyx mori (Lepidoptera: Bombycidae): High variability and potential for strain identificationKee Young KIM, Eun Lee MEE, In Lee HEE, Mee Hong YEON, Pil Don KANG, Kwang Ho CHOI, Zhong Zheng GUI, Byung Rae JIN, Jae Sam HWANG, Kang Sun RYU, Yeon Soo HAN, Iksoo KIMEur. J. Entomol. 105 (1): 73-80, 2008 | DOI: 10.14411/eje.2008.010 We sequenced nine introns of 25 silkworm (Bombyx mori L.) strains, assuming that the introns are particularly prone to mutation. Mean sequence divergence and maximum sequence divergence in each intronic sequence among 25 silkworm strains ranged from 0.81% (3.8 nucleotides) ~ 9.15% (85.2 nucleotides) and 1.2% (seven nucleotides) ~ 39.3% (366 nucleotides), respectively. The degree of sequence divergence in some introns is very variable, suggesting the potential of using intronic sequences for strain identification. In particular, some introns were highly promising and convenient strain markers due to the presence of a large indels (e.g., 403 bp and 329 bp) in only a limited number of strains. Phylogenetic analysis using the individual or the nine concatenated intronic sequences showed no clustering on the basis of known strain characteristics. This may further indicate the potential of the intronic sequences for the identification of silkworm strains. |
Rhythmic oscillations of α-amylase protein and its enzymatic activity levels in Drosophila melanogaster (Diptera: Drosophilidae)Marcin A. CIUK, Piotr BEBAS, Bronislaw CYMBOROWSKIEur. J. Entomol. 106 (4): 519-528, 2009 | DOI: 10.14411/eje.2009.065 In this report, we show that α-amylase activity is rhythmic in the wild-type fruit fly Drosophila melanogaster, and that this rhythm exhibits the properties of a clock output. Moreover, the rhythm of amylase activity is accompanied by fluctuations in the Amy protein level under 12L : 12D conditions. A strong sexual dimorphism is evident in the oscillations of Amy protein and enzymatic activity. Under light : dark (LD) conditions on the control diet, CantonS wild-type Drosophila melanogaster exhibit a bimodal rhythm of amylase activity, particularly of the AmyD3 (Amy3) isoform, with morning and evening peaks. Under these conditions, Amy protein levels also oscillate significantly, again more strongly for the Amy3 isoform than Amy1 (Amy1). A robust oscillation of Amy3 and Amy1 activity is also observed under DD conditions for both sexes. In constant light (LL) the rhythms dampen out, particularly in the males. A high level of dietary glucose causes an overall decrease in the amplitudes of the rhythmic oscillations of amylase activity, but the processes are nevertheless rhythmic, with peak activities at Zt8 for the females, and at Zt0 for the males in LD. In constant darkness (DD) the rhythms are maintained. Mutants lacking a functioning oscillator, per01, exhibit a slight photoperiodicity in LD, with a decrease in amylase activity in both males and females during the late night in LD, but no rhythmic oscillations in DD. |
Female reproductive patterns in the millipede Polydesmus angustus (Diplopoda: Polydesmidae) and their significance for cohort-splittingJean-François DAVIDEur. J. Entomol. 106 (2): 211-216, 2009 | DOI: 10.14411/eje.2009.027 First-stadium juveniles of Polydesmus angustus born each month from May to September were reared throughout their life cycle under controlled seasonal conditions. At maturity, the reproductive patterns of 62 females were studied individually. It was confirmed that females born from May to August have a 1-year life cycle and those born from late August onwards a 2-year life cycle (cohort-splitting). A third type of life cycle - interseasonal iteroparity - was observed in a few females born late in the season. On average, annual females started to reproduce when 11.4 months old and produced 3.6 broods per female over 1.8 months; the later they were born from May to August, the later they reproduced the following year. Biennial females started to reproduce when 19.9 months old and produced 3.8 broods per female over 2.2 months; all reproduced early in the breeding season. These results indicate that only annual females can produce an appreciable proportion of biennial offspring from late August onwards, which rules out direct genetic determination of life-cycle duration. The reproductive characteristics of P. angustus suggest a non-genetic mechanism that can drive cohort-splitting. Because individual females reproduce for about 2 months on average, this automatically results in cyclic variation in life-cycle duration (annual/biennial/annual) in the long-term progeny of any female. |
Differences in the development of the closely related myrmecophilous butterflies Maculinea alcon and M. rebeli (Lepidoptera: Lycaenidae)Marcin SIELEZNIEW, Anna M. STANKIEWICZEur. J. Entomol. 104 (3): 433-444, 2007 | DOI: 10.14411/eje.2007.063 The initially phytophagous caterpillars of Maculinea alcon and M. rebeli complete their development in Myrmica ant colonies as social parasites. Recent genetic studies show no differences at the species level among various populations of each butterfly taxa. Usually M. alcon and M. rebeli are identified by habitat and larval food plants (Gentianaceae) and host ant specificity is also considered to be an important feature. However most of the ecological characteristics overlap at least in some parts of their distributions. The developmental and survival characteristics of caterpillars reared by different Myrmica species were compared in laboratory experiments and in the field. Morphologically indistinguishable M. alcon and M. rebeli, which originated from Polish populations, are very similar in terms of host specificity i.e. larvae survived both with M. scabrinodis and M. sabuleti. However they showed different growth characteristics. The earlier flight period of M. rebeli, which is synchronized with the phenology of Gentiana cruciata, resulted from the quick growth of caterpillars in Myrmica nests in the pre-winter phase, when they gained about half of their final body biomass. After the end of winter they recommenced growth almost immediately. M. alcon larvae entered diapause shortly after adoption by ants and began to increase in weight significantly just one month after the onset of spring, which synchronized their development with that of their larval food plant, G. pneumonanthe. Therefore neither population group is transferable between habitats and should still be regarded, at least, as distinct conservational units. |
Hedyselmis opis: Description of the larva and its phylogenetic relation to Graphelmis (Coleoptera: Elmidae: Elminae)Fedor ÈIAMPOR Jr., Ignacio RIBERAEur. J. Entomol. 103 (3): 627-636, 2006 | DOI: 10.14411/eje.2006.084 The riffle beetle genus Hedyselmis Hinton, 1976 includes two species from the Malay Peninsula, with adults with a highly deviating morphology. Its phylogenetic relationships are unclear, although it has been hypothesized to be related to Graphelmis Delève, 1968, a large genus widely distributed in the Oriental and East Palaearctic regions. In this paper the larva of H. opis Hinton, 1976 is described based on material collected in the Cameron Highlands (Malaysia) and the conspecificity with co-existing adults tested using sequences of one nuclear (5' end of 18S rRNA) and three mitochondrial gene fragments (5' end of the large ribosomal unit + tRNAleu + 5' end of the NADH dehydrogenase subunit 1; 5' end of cytochrome c oxidase subunit I; and a fragment of cytochrome b) with a total of ca. 2,600 bp. This is the first example of the use of molecular data to match different life stages within the family Elmidae. The larva of H. opis has a subcylindrical body typical of many other elmid genera; abdominal segments 1-7 with preserved pleura; and ninth segment with oval operculum. The last instar larvae have clearly visible prominent spiracles on mesothorax and abdominal segments 1-8. The phylogenetic position of Hedyselmis in relation to Graphelmis was investigated using molecular data for three species of Graphelmis plus a selection of other Elmidae genera. Hedyselmis opis is nested within Graphelmis, confirming their close relationship and suggesting that their status requires taxonomic revision. |
Isolation and characterization of polymorphic microsatellite loci in the bamboo locust Rammeacris kiangsu (Orthoptera: Acrididae)Wen-Juan XUAN, Yan-Yan ZHANG, Na-Na LIU, Jin-Liang ZHAO, Guo-Fang JIANGEur. J. Entomol. 106 (4): 663-665, 2009 | DOI: 10.14411/eje.2009.082 Twelve polymorphic microsatellite loci were developed and characterized from the bamboo locust, Rammeacris kiangsu, based on enriched genomic libraries. Analysis of 30 individuals showed that the number of alleles ranged from seven to 25 with the observed heterozygosity ranging from 0.333 to 0.767 and expected heterozygosity from 0.784 to 0.963. Test of cross-species amplification showed that some of these microsatellite markers could be used for studying other species such as Ceracris nigricornis, C. fasciata, and Chorthippus brunneus. |
Genetic and physiological variation among sexual and parthenogenetic populations of Asobara japonica (Hymenoptera: Braconidae), a larval parasitoid of drosophilid fliesYusuke MURATA, Shinsuke IDEO, Masayoshi WATADA, Hideyuki MITSUI, Masahito T. KIMURAEur. J. Entomol. 106 (2): 171-178, 2009 | DOI: 10.14411/eje.2009.020 We studied variations in genetic, physiological, and ecological traits, and the phylogenetic relationship among sexual and parthenogenetic populations of Asobara japonica, a larval parasitoid of drosophilid flies, in order to understand how they adapt to local environments and have differentiated. The strain from Iriomote-jima (IR) differed from other Japanese strains in the nucleotide sequences of its cytochrome oxidase subunit I (COI) and in not undergoing diapause and having a shorter preimaginal period and a higher adult tolerance of cold. The strains other than IR showed a low level of nucleotide variation in COI but varied in their mode of reproduction; the strains from the Ryukyu Islands were sexual, whereas those from the main islands of Japan and Ogasawara were parthenogenetic. In addition, strains from higher latitudes generally showed a high incidence of diapause, although there were some exceptions. On the other hand, preimaginal period and adult cold tolerance varied little among the strains excluding IR, and pupal cold tolerance, oviposition preference and incidence of parasitism varied little among the strains including IR. Evolution and environmental adaptations in this species are discussed, particularly focusing on parthenogenetic populations. |
Chromosomal differentiation among bisexual European species of Saga (Orthoptera: Tettigoniidae: Saginae) detected by both classical and molecular methodsEl¿bieta WARCHA£OWSKA-¦LIWA, Beata GRZYWACZ, Anna MARYAÑSKA-NADACHOWSKA, Tatjana V. KARAMYSHEVA, Nikolai B. RUBTSOV, Dragan P. CHOBANOVEur. J. Entomol. 106 (1): 1-9, 2009 | DOI: 10.14411/eje.2009.001 We report the karyotype characteristics including chromosome numbers of Saga campbelli campbelli, S. c. gracilis, and S. rammei using the following classical cytogenetic methods: C-banding, silver staining, and fluorochrome staining DAPI and CMA3. We also present FISH data showing the distribution of telomeric repeats and 18S rDNA on the chromosomes of these species and the results of similar studies cited in the literature on S. hellenica, S. natoliae, and S. rhodiensis. The five European Saga species exhibit a high rate of karyotype evolution. In addition to changes in chromosome number and morphology (by chromosomal inversion and/or chromosome fusion), interspecific autosomal differentiation involved changes in the distribution and quantity of constitutive heterochromatin and GC-rich regions, as well as the number and location of NORs. In the present study we focused on testing a hypothetical model of karyotype evolution in Saga, with particular reference to the cytogenetic mapping of rDNA and telomeric sequences. Variation in the distribution of rDNA and location of Ag-NORs are novel phylogenetic markers for the genus Saga. |
Forgotten natural enemies: Interactions between coccinellids and insect-parasitic fungiHelen E. ROY, Ted E. COTTRELLEur. J. Entomol. 105 (3): 391-398, 2008 | DOI: 10.14411/eje.2008.049 The role of predators and parasitoids in the regulation of insect populations is widely reported in the context of both pest and non-pest insects. However, this is not the case for pathogens (entomopathogens). Indeed, most studies on insect life history refer only to predators and parasitoids when considering natural enemy guilds, even though naturally occurring entomopathogens are undoubtedly more diverse and widespread. This is certainly the case with the Coccinellidae; the natural enemies of coccinellids have been the subject of a number of review articles but pathogens receive only brief mention. In this review we attempt to address the balance and consider the interactions of natural populations of Coccinellidae with entomopathogenic fungi. Most research on entomopathogens and Coccinellidae focuses on the non-target impact of biorational insecticides against coccinellids and the impact of fungal infections upon aggregations of overwintering coccinellids; with the former overwhelmingly dominating the literature. Given the prominence of coccinellids in classical and conservation biological control, it is surprising that studies have not measured the natural impact of pathogenic fungi upon introduced species or natural populations of Coccinellidae, as has been done with numerous insect pest species. Here we review the literature on the intriguing interactions between coccinellids and fungal pathogens. We examine the literature on direct infection (sub-lethal and lethal) of coccinellids by pathogenic (Beauveria bassiana, Metarhizium anisopliae, Paecilomyces fumosoroseus) or parasitic (Hesperomyces virescens). We also consider the role of intra-guild predation (on the aphid-specific fungus Pandora neoaphidis and Beauveria bassiana) and finally indirect interactions such as coccinellids dispersing P. neoaphidis. We suggest that fungal pathogens are all too often forgotten natural enemies and future research should address the profound absence of knowledge in this field. |
Influence of abiotic factors on some biological and ecological characteristics of the aphid parasitoid Aphelinus asychis (Hymenoptera: Aphelinidae) parasitizing Aphis gossypii (Sternorrhyncha: Aphididae)Stefanie SCHIRMER, Cetin SENGONCA, Peter BLAESEREur. J. Entomol. 105 (1): 121-129, 2008 | DOI: 10.14411/eje.2008.017 The current laboratory study was designed to evaluate the effect of abiotic and biotic factors such as temperature, light intensity, relative humidity and host age on biological and ecological characteristics of Aphelinus asychis (Walker) parasitizing Aphis gossypii (Glover). The traits studied were developmental duration, mortality, sex ratio, longevity, fecundity and host feeding. A. asychis can completely develop and reproduce at temperatures 18°C and 30°C, light intensities of 1000 and 7000 lux and relative humidities of 30% and 60%. Temperature had a significant effect on the developmental duration as well as on the percentage and longevity of females, while mortality from mummification to emergence, fecundity and host feeding were only slightly affected. Relative humidity only affected the developmental duration of A. asychis. Light intensity had mostly affected the biological and ecological traits of A. asychis. High light intensity resulted in a shorter developmental duration, higher incidence of females and longer life span of the female parasitoid. A high tolerance to climatic variations and life cycle well adapted to this aphid host are properties that make it likely that A. asychis could be used for the biological control of the cotton aphid in greenhouses. |
Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotationAlberto BRESSAN, Werner E. HOLZINGER, Benoit NUSILLARD, Olivier SÉMÉTEY, Frédéric GATINEAU, Mauro SIMONATO, Elisabeth BOUDON-PADIEUEur. J. Entomol. 106 (3): 405-413, 2009 | DOI: 10.14411/eje.2009.052 Cixiid planthoppers have been shown to vector phloem-limited prokaryotes associated with plant diseases world-wide. In eastern France, an emerging disease of sugar beet called syndrome "basses richesses" has been associated with phloem-restricted bacteria transmitted by a cixiid planthopper within the genus Pentastiridius. Early investigation suggested the species being Pentastiridius beieri. On the basis of a morphological and phylogenetic study we report the identification of the planthopper as Pentastiridius leporinus. Furthermore we report some biological traits of the species, which shows a surprising ecological adaptation to an annual cropping rotation sugar beet-winter cereals. |
A landscape view of cereal aphid parasitoid dynamics reveals sensitivity to farm- and region-scale vegetation structureMichael J. BREWER, Takuji NOMA, Norman C. ELLIOTT, Alexandra N. KRAVCHENKO, Ann L. HILDEur. J. Entomol. 105 (3): 503-511, 2008 | DOI: 10.14411/eje.2008.066 Functioning of plant-aphid-natural enemy interactions may be associated with the structure and composition of withinfield vegetation, neighborhood fields and field borders, and the regional plant community of cropped and noncropped areas. Farmand region-scale vegetation in the wheat-growing area of the North American Great Plains was hypothesized to effect the abundance of two hymenopteran parasitoids, that differ in physiological and behavioral attributes, of the key pest aphid of wheat, Diuraphis noxia (Mordvilko). The parasitoids had greater sensitivity to farm-scale vegetation (wheat strip rotation with or without spring-sown sunflower) than region-scale vegetation (degree of diversification with other crops and wheat fields converted to conservation grasslands). A two-way factorial design of scale (farm- and region-scale) revealed that parasitoid abundance in grass-dominant (homogeneous) areas especially benefited from adding sunflower to the wheat-fallow strip crop rotation. Considerable sensitivity of the analysis was added when adjusting for seasonality of vegetation, revealing that the region-scale effects were most prominent late season. From a management viewpoint, adding sunflower into the wheat production system, especially in relatively homogeneous vegetation regions, tends to promote local parasitoid populations during the summer when spring-sown plants are maturing and wheat is not in cultivation. Contrasting results for A. albipodus and L. testaceipes were consistent with expectations based on behavioral and physiological attributes of the two aphid parasitoid families they represent. Still, the general management interpretation seems robust for the two parasitoids and has relevance to both farm- and region-scale management schemes that are occurring in the wheat production zone of North American Great Plains. |
Flower visiting Neuroptera: Mouthparts and feeding behaviour of Nemoptera sinuata (Nemopteridae)Harald W. KRENN, Barbara-Amina GEREBEN-KRENN, Bernhardt M. STEINWENDER, Alexi POPOVEur. J. Entomol. 105 (2): 267-277, 2008 | DOI: 10.14411/eje.2008.037 The mouthparts of the spoon-winged lacewing Nemoptera sinuata are adapted for the uptake of pollen and nectar. Form and function of the mouthparts are described, and the technique of food uptake is discussed in context with flower-visiting behaviour and floral architecture of the preferred flowers. The maxillae are the main organs for food uptake. The brush-shaped laciniae, galeae and maxillary palpi form a functional unit which can be extended by the action of the cardo-stipes joint. Video analyses of the mouthpart movements distinguished different patterns of maxillary motions which occur in nectar feeding or pollen collecting. The flower-visiting behaviour and the specialised mouthparts of the Nemopteridae are derived traits which probably evolved from predatory and biting/chewing mouthparts within the Neuroptera. |
Effect of female size on host selection by a koinobiont insect parasitoid (Hymenoptera: Braconidae: Aphidiinae)Dionyssios LYKOURESSIS, Nikolaos GARANTONAKIS, Dionyssios PERDIKIS, Argyro FANTINOU, Andronikos MAUROMOUSTAKOSEur. J. Entomol. 106 (3): 363-367, 2009 | DOI: 10.14411/eje.2009.046 Body size is a main fitness component of insect parasitoids. We assessed the potential influence of maternal size of the parasitoid wasp Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae) on its ability to parasitize the different instars of Aphis gossypii Glover (Hemiptera: Aphididae) on eggplant and cucumber. In the experiments "small" vs "large" parasitoid females were used. Females oviposited in all instars but more of the smaller hosts were parasitized. Host selection was affected by female size and the larger hosts were more frequently mummified by the large than the small females. Thus, parasitoid female size influenced host selection. This could affect the potential of the parasitoid to exploit populations of aphids that differ in their size structure. The importance of these results in terms of the ecological adaptations of the parasitoid and their implication for biological control are discussed. |
Differences in mating strategies in two closely related small ermine moth species (Lepidoptera: Yponomeutidae)Aletta C. BAKKER, Wil E. VAN GINKEL, Peter ROESSINGH, Steph B.J. MENKENEur. J. Entomol. 105 (2): 219-226, 2008 | DOI: 10.14411/eje.2008.031 The degree of polyandry in a species is linked to other life history traits such as egg maturation, life span, and male ejaculate size and quality. The study of differences in mating strategies between closely related species can provide a better understanding of the evolution of these strategies and of sperm competition. Mating patterns of two closely related species of small ermine moths (Yponomeuta) were investigated in the laboratory. The average female age at first mating was higher in Y. cagnagellus than in Y. padellus. Both species mated more than once; however, Y. cagnagellus females were more likely to remate in a short time frame. Moreover, Y. cagnagellus had higher life time female mating frequencies than Y. padellus (viz., 3.0 versus 2.0). These differences in mating frequency were confirmed in the field by examining the presence of spermatophores (or their remains) in the bursa as well as sperm in the spermatheca of field-caught females. |
Taxonomy of the genera Scaeva, Simosyrphus and Ischiodon (Diptera: Syrphidae): Descriptions of immature stages and status of taxaPavel LÁSKA, Celeste PÉREZ-BAÑÓN, Libor MAZÁNEK, Santos ROJO, Gunilla STÅHLS, M. Angeles MARCOS-GARCÍA, Vítìzslav BIÈÍK, Jindra DU©EKEur. J. Entomol. 103 (3): 637-655, 2006 | DOI: 10.14411/eje.2006.085 A review of all known descriptions of immature stages of the species of the genera Scaeva Fabricius, 1805, Ischiodon Sack, 1913 and Simosyrphus Bigot, 1882 is presented using SEM illustrations. The third instar larval and/or pupal morphology of Scaeva dignota (Rondani, 1857), Scaeva mecogramma (Bigot, 1860) and Simosyrphus grandicornis (Macquart, 1842) are newly described. All species of the genera studied in this paper are very similar for all the studied characters of their immature stages, including the chaetotaxy. Molecular characters of the mitochondrial cox1 gene (1128bp) were used for inferring relationships of the studied taxa. The nuclear internal transcribed spacer 2 (ITS2) was additionally applied for species delimitation of the closely related species Scaeva selenitica and S. dignota. The Palaearctic Scaeva species could be split into two groups based on the analysis of morphology of posterior respiratory process. These groups were previously diagnosed as S. selenitica-group [i.e., S. selenitica (Meigen, 1822), S. dignota (Rondani, 1857), S. mecogramma (Bigot, 1860)] and S. pyrastri-group [i.e., S. pyrastri (Linnaeus, 1758), S. albomaculata (Macquart, 1842), S. latimaculata (Brunetti, 1923)]. Semiscaeva Kuznetzov, 1985 and Scaeva Fabricius, 1805 are the available names for these two natural groups that should be classified as subgenera; the former name is proposed for S. selenitica-group and the latter for S. pyrastri-group. Mecoscaeva Kuznetzov, 1985 syn. n. is transferred as a junior synonym of the subgenus Semiscaeva Kuznetzov, 1985 according to the principle of the first reviser. Based on the analysis of immature stages, the generic name Ischiodon Sack, 1913 syn. n. is proposed as a junior synonym of the genus Simosyrphus Bigot, 1882. The similarity of immature stages between Scaeva s. str. and Simosyrphus grandicornis Macquart, 1842, Simosyrphus aegyptius (Wiedemann, 1830) comb. n. and Simosyrphus scutellaris (Fabricius, 1805) comb. n. is discussed. All the proposed subgeneric and generic taxa based on morphological studies received high support employing molecular characters. |
Purification and characterization of a novel thermoacidophilic and thermostable α-mannosidase from the digestive fluid of oil palm weevil Rhynchophorus palmarum (Coleoptera: Curculionidae) larvaeMicaël BÉDIKOU, Pascal AHI, Martial KONÉ, Betty FAULET, Jean GONNETY, Patrice KOUAMÉ, Sébastien NIAMKÉEur. J. Entomol. 106 (2): 185-191, 2009 | DOI: 10.14411/eje.2009.022 An extracellular α-mannosidase with unusual properties was purified from the digestive fluid of oil palm weevil (Rhynchophorus palmarum Linnaeus) larvae using ammonium sulphate saturation, size exclusion and anion-exchange chromatography. The enzyme named RpltM is thermoacidophilic, thermostable and behaves like lysosomal α-mannosidase (EC 3.2.1.24). The molecular weight, Km value, optimum reaction temperature and pH are 108-112 kDa, 0.36 mM, 65°C and 4.5, respectively. Zn2+ enhanced whereas Cu2+, Sodium dodecyl sulphate, swainsonine and 1,4-dideoxy-1,4-iminomannitol strongly inhibited its hydrolytic activity. The enzyme was stable for 25 min at 65°C and retained 70% of its initial activity after 60 min. At 70°C, around 60% of this activity was conserved after 25 min. RpltM retained more than 90% of its activity over a pH range of 4.2 to 5.0 and remained fully active in the presence of detergents such as nonidet P-40, triton X-100, polyoxyethylen-10-oleyl ether (up to 1%, w/v), dithiothreitol and β-mercaptoethanol. The stability under these conditions is also better than that reported for other insect α-mannosidases. Thus, RpltM could be used as an important bioindustrial tool for removing mannose residues from oligosaccharides. |
Host ant specificity of large blue butterflies Phengaris (Maculinea) (Lepidoptera: Lycaenidae) inhabiting humid grasslands in East-central EuropeMagdalena WITEK, Ewa B. ¦LIWIÑSKA, Piotr SKÓRKA, Piotr NOWICKI, Marta WANTUCH, Vladimír VRABEC, Josef SETTELE, Michal WOYCIECHOWSKIEur. J. Entomol. 105 (5): 871-877, 2008 | DOI: 10.14411/eje.2008.115 Butterflies of the genus Phengaris have a highly specialised life cycle involving an obligatory relationship with Myrmica ants. A knowledge of the host ant specificity is essential for understanding the relationship between a particular Phengaris species and its hosts and also important for the conservation of these butterflies. Data on host ant specificity were collected in Poland, the Czech Republic, Slovakia and Ukraine. Five different Myrmica species were used by P. teleius as hosts (M. scabrinodis, M. rubra, M. ruginodis, M. rugulosa and M. gallienii) and at most localities it was not possible to distinguish a primary host - i.e. several Myrmica species were parasitized to similar extents. Three populations of P. nausithous were found in Poland and Ukraine. In every case, M. rubra was its primary host, although in the Kraków region (Poland) two nests of M. scabrinodis and two of M. ruginodis were infested by this butterfly species. P. alcon in the four populations investigated in Poland and Ukraine invariably only used M. scabrinodis as a host despite the presence of other Myrmica species. These results obtained suggest lack of host specificity in P. teleius and high host specificity in P. nausithous, which mainly uses M. rubra as its host across Europe. Moreover, the three populations of P. alcon investigated seem to be highly specific and use M. scabrinodis as a host, which confirms the high local specialisation of these populations. |
Repellency of conspecific and heterospecific larval residues to Hippodamia convergens (Coleoptera: Coccinellidae) ovipositing on sorghum plantsJ.P. MICHAUD, J.L. JYOTIEur. J. Entomol. 104 (3): 399-405, 2007 | DOI: 10.14411/eje.2007.059 We examined oviposition decisions by Hippodamia convergens Guérin in semi-natural arenas in the laboratory. Gravid females were presented individually with an array of four young sorghum plants, Sorghum bicolor, bearing (1) no additional stimulus, (2) an established colony of greenbug, Schizaphis graminum Rondani, (3) residues of conspecific larvae, and (4) greenbugs plus residues of conspecific larvae. Females laid no egg masses on type 3 plants, significantly fewer than expected by chance on type 4 plants, and significantly more on type 1 plants, with type 2 plants receiving expected numbers. Females laid 50% of egg masses on elements of the arena other than the plants, especially the cage screen, suggesting that females sought to distance their eggs farther from larval residues than the spacing of plants in the arena permitted (15 cm). When the experiment was repeated with plants exposed to larvae of Coleomegilla maculata DeGeer, the repellency was weaker. Once again, clean plants were the most preferred and aphids did not increase the acceptability of plants with larval residues. Nevertheless, only 18% of egg masses occurred off the plants and larval residues did not reduce the acceptability of aphid-bearing plants as did conspecific larval residues. Simultaneous choice tests conducted with individual third instars of both species revealed that C. maculata larvae consumed H. convergens eggs as readily as conspecific eggs, but H. convergens larvae preferred conspecific eggs to those of C. maculata. We conclude that H. convergens oviposition decisions are shaped by the risks of both egg cannibalism and predation. |
Why does the Namib Desert tenebrionid Onymacris unguicularis (Coleoptera: Tenebrionidae) fog-bask?Strinivasan G. NAIDUEur. J. Entomol. 105 (5): 829-838, 2008 | DOI: 10.14411/eje.2008.110 Dehydration of Onymacris unguicularis (Haag) for 10 days at 27°C resulted in a weight loss of 14.9%, and a 37% decrease in haemolymph volume. Although there was an overall decrease in the lipid content during this period, metabolic water production was insufficient to maintain total body water (TBW). Rehydration resulted in increases in body weight (6.2% of initial weight), TBW (to normality), and haemolymph volume (sub-normal at the end of rehydration). Despite an increase of 44.0 mg in the wet weight of O. unguicularis after drinking for 1h, there was little change in the water content at this time, although the total lipid content increased significantly. Increases in haemolymph osmolality, sodium, potassium, chloride, amino acid and total sugar concentrations during dehydration were subject to osmoregulatory control. No evidence of an active amino acid-soluble protein interchange was noted during dehydration or rehydration. Haemolymph trehalose levels were significantly increased at the end of rehydration (relative to immediate pre-rehydration values), indicating de novo sugar synthesis at this time. Osmotic and ionic regulation was evident during rehydration, but control of OP during haemolymph-dilution is poor and accomplished largely by the addition to the haemolymph of free amino acids and solute(s) not measured in this study. There was little mobilization of sodium and chloride ions from storage sites at this time. The lesser osmoregulatory ability of Onymacris unguicularis and perhaps earlier susceptibility to osmotic stress, a significantly high normal blood glycerol level (relative to other diurnal adesmiine tenebrionids), and a water storage mechanism associated with synthesis of fat, probably all contribute to the development of fog-basking behaviour in this species. Water gain in O. unguicularis during periods of relative drought is probably largely accomplished by a greater food consumption. |
Cladistic analysis of Sericania (Coleoptera: Scarabaeidae: Sericini) - implications for the evolution of the xerophilous fauna of the HimalayaDirk AHRENSEur. J. Entomol. 104 (3): 517-530, 2007 | DOI: 10.14411/eje.2007.072 A cladistic analysis of the species of Sericania Motschulsky, 1860, was executed using fifty-six morphological characters of adults. The monophyly of the genus is supported by the phylogenetic trees generated. Among the three major lineages indicated by the strict consensus tree the East Asian Sericania fuscolineata lineage represents the genus Sericania as defined "originally" and adopted by subsequent authors. The second, the clade Sericania nepalensis group + Sericania sp. 2, is a sister group to the S. fuscolineata clade. Both constitute a sister group to the third major lineage, the Sericania kashmirensis clade, which is endemic in the drier North-West Himalaya where it is the most diverse monophyletic group of Sericini. Provided that the stem species of the S. kashmirensis clade was xerophilous, the origin of this clade can not predate the early Miocene. Based on paleoclimatical and geological data, two competing hypotheses are proposed to explain the evolution of the xerophilous Sericania lineage: (a) a basal splitting within Sericania occurred because of the altitudinal and climatic barrier posed by the Himalaya, which separated the xerophilous lineage in the north (Tibet) from the hygrophilous lineage in the south-east (S slope of Himalaya/ Tibet), or (b) it was a consequence of the increase in the climatic east-west contrast along the southern slope of the Himalaya, which strengthened with the onset of monsoons 8 Ma ago. |
Mesostigmatid mites associated with the dung beetle Copris lunaris (Coleoptera: Scarabaeidae)Peter MA©ÁN, Bruce HALLIDAYEur. J. Entomol. 106 (4): 545-550, 2009 | DOI: 10.14411/eje.2009.068 We examined the mesostigmatid mites found in four nest chambers of the dung beetle Copris lunaris (Scarabaeidae) in Slovakia. A total of 763 mites was found, belonging to ten species. The most frequent and abundant species were Pelethiphis opacus, Macrocheles copridis, Parasitus copridis, Uropoda copridis, Copriphis pterophilus, and Onchodellus hispani. The nests contained 19 dung balls, each enclosing a beetle pupa. Altogether 472 mites were found in these brood balls. A further 291 mites were found on the parental beetles in the nests. Three mite species were clearly more abundant in brood balls than on parental beetles, and these belonged to the life cycle stage that disperses by phoresy. The mites found in brood balls apparently disperse on the young adult beetles when they emerge. Only Parasitus copridis was more abundant on parental beetles than in brood balls. Different species of mites have developed different strategies for dispersal, as shown by their preferential attachment to either the parental or progeny generations of beetles. |
Heteropterans as aphid predators in inter-mountain alfalfaXavier PONS, Belén LUMBIERRES, Ramon ALBAJESEur. J. Entomol. 106 (3): 369-378, 2009 | DOI: 10.14411/eje.2009.047 The relationships between predatory Heteroptera and their potential prey species were investigated during two crop seasons in an inter-mountain area close to the Pyrenees (Iberian Peninsula). Regression was used to analyze the potential numerical responses shown by heteropterans to aphids and other potential prey during alfalfa intercuts (the plant growth period between cuts) of high aphid occurrence. The most abundant heteropterans were Orius spp., Nabis spp. and mirids, and all were present in alfalfa stands throughout the season. Acyrthosiphon pisum was the prevalent species during the 2nd intercut, Therioaphis trifolii during the 4th and Aphis craccivora during the 5th. We performed simple regression analysis between the Orius sp., Nabis sp. and mirids and the prevalent aphid species, forward multiple regression analysis between heteropterans and all possible soft-bodied prey species; and both analyses for coccinellids, as relative aphid predator specialists. The heteropterans responded numerically to A. pisum but not to T. trifolii or A. craccivora. Heteropterans also showed numerical responses to other potential prey (leafhoppers, thrips, and other soft bodied prey) that remained at low densities throughout the season. All these preys may contribute to the presence of heteropterans in alfalfa stands throughout the season. The results suggest that heteropterans may contribute to reduce A. pisum, particularly at the beginning of the growing season, and on other potential pests when they invade or recolonize alfalfa, and may help to delay or prevent the build-up of these pest populations. |
Long-distance wind-borne dispersal of the moth Cornifrons ulceratalis (Lepidoptera: Crambidae: Evergestinae) into the northern MediterraneanJordi DANTART, Constantí STEFANESCU, Anna ÀVILA, Marta ALARCÓNEur. J. Entomol. 106 (2): 225-229, 2009 | DOI: 10.14411/eje.2009.030 On October 2006, during an episode of abnormally warm weather, the African moth Cornifrons ulceratalis (Lederer, 1858) was captured simultaneously for the first time in several sites in north-eastern Spain, the Balearic Islands and southern France. A deep depression situated over the Atlantic at the time gave rise to warm south-westerly winds, accompanied by suspended dust, that blew towards the north-western Mediterranean Basin. Back trajectories of air masses at two different altitudinal levels indicate that the moths most probably originated from an area located in Morocco and northern Algeria, where C. ulceratalis can be extremely abundant. With winter approaching, this invasion of a typically non-migratory species into the north-western Mediterranean Basin provides a good example of the so-called "pied piper" phenomenon, by which wind-borne insects may be carried into areas unfavourable for survival or reproduction. However, because climate change may make the establishment of this and other African species more likely in the future, we suggest that monitoring of this process may become an essential issue in the coming years. |
Afromontane Coelocorynus (Coleoptera: Scarabaeidae: Cetoniinae): Larval descriptions, biological notes and phylogenetic placementPetr ©ÍPEK, Bruce D. GILL, Vasily V. GREBENNIKOVEur. J. Entomol. 106 (1): 95-106, 2009 | DOI: 10.14411/eje.2009.014 This paper reports the collecting of adult beetles and third-instar larvae of Coelocorynus desfontainei Antoine, 1999 in Cameroon and provides new data on the biology of this high-altitude Afromontane genus. It also presents the first diagnosis of this genus based on larval characters and examination of its systematic position in a phylogenetic context using 78 parsimony informative larval and adult characters. Based on the results of our analysis we (1) support the hypothesis that the tribe Trichiini is paraphyletic with respect to both Valgini and the rest of the Cetoniinae, and (2) propose that the Trichiini subtribe Cryptodontina, represented by Coelocorynus, is a sister group of the Valgini: Valgina, represented by Valgus. The larvae-only analyses were about twofold better than the adults-only analyses in providing a phylogenetic resolution consistent with the larvae + adults analyses. Only one of the ten clades was consistently supported by the analyses of both the larval and adult datasets, while the remaining nine were invariably strongly supported by one but not the other analysis, thus highlighting the importance of employing different data sources. |
Experimental hybridization between X0 and XY chromosome races in the grasshopper Podisma sapporensis (Orthoptera: Acrididae). II. Cytological analysis of embryos and adults of F1 and F2 generationsEl¿bieta WARCHA£OWSKA-¦LIWA, Alexander G. BUGROV, Yoshikazu SUGANO, Anna MARYAÑSKA-NADACHOWSKA, Shin-Ichi AKIMOTOEur. J. Entomol. 105 (1): 45-52, 2008 | DOI: 10.14411/eje.2008.006 Experimental hybridization of X0 and XY chromosome races of the brachypterous grasshopper P. sapporensis did not reveal pre-zygotic reproductive isolation. However, a partial zygotic barrier was found between the X0-standard race from Shimokawa and XY-standard chromosome race from Akan. Approximately 40% of embryos from females crossed with males from other chromosome races developed parthenogenetically, the remaining embryos were normal heterozygotes. Adult F1 males and females from crosses of this type had properly developed testes and ovaries. Non-sister associations and other irregularities in meiosis were not observed in male meiosis. Crossing experiments demonstrated that hybrids between X0 and XY races occur to some extent. The absence of a hybrid zone between the X0 and XY chromosome races may be the result of selection against heterozygotes. Crosses between the XY-Tanno and X0-standard (Teine) subraces resulted in F1 and F2 generations in spite of the many chromosome differences between them such as a X-A translocation and fixed pericentric inversions in four pairs of autosomes. These results do not support the hypothesis that chromosomal differences play a key role in restricting gene flow between the X0 and XY races of P. sapporensis. |
Morphology, bioacoustics and phylogeography of the Isophya major group (Orthoptera: Tettigoniidae: Phaneropterinae): A species complex occurring in Anatolia and CyprusHasan SEVGILI, Battal ÇIPLAK, Klaus Gerhard HELLER, Ali DEMIRSOYEur. J. Entomol. 103 (3): 657-671, 2006 | DOI: 10.14411/eje.2006.086 The species of the Isophya major-group (Orthoptera: Tettigoniidae: Phaneropterinae), are reviewed. I. major Brunner von Wattenwyl and I. mavromoustakisi Uvarov are redescribed. Two new species are described; Isophya mersinensis Sevgili & Çiplak sp. n. and Isophya salmani Sevgili & Heller sp. n. from south Anatolia. Illustrations of morphology and male calling song are provided and a detailed comparison of the four species in the group is presented. We conclude that these four species constitute a natural group in sharing male cerci with two or more denticles not ordered in a line, a character unique to this species group within the genus. From an evaluation of their morphology and song characteristics, relationships among the species in the group are I. major + (I. mersinensis sp. n. + (I. salmani + I. mavromoustakisi). Based on the the distribution pattern and habitat preference, we concluded that the division of I. salmani and I. mavromoustakisi was a vicariant event resulting from the separation of Cyprus and Anatolia due to reflooding of the Mediterranean after the Messinian salinity crisis at the beginning of the Pliocene, around 5 My ago. |



