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Changes in the volatile profile of Brassica oleracea due to feeding and oviposition by Murgantia histrionica (Heteroptera: Pentatomidae)Eric CONTI, Claudia ZADRA, Gianandrea SALERNO, Benedetta LEOMBRUNI, Daniela VOLPE, Francesca FRATI, Cesare MARUCCHINI, Ferdinando BINEur. J. Entomol. 105 (5): 839-847, 2008 | DOI: 10.14411/eje.2008.111 The mixture of volatile compounds emitted by Brassica oleracea var. sabauda changed significantly in response to feeding and/or oviposition by Murgantia histrionica (Heteroptera: Pentatomidae). Volatiles were collected from (1) healthy plants and those with (2) feeding punctures, (3) a combination of feeding punctures and oviposition, (4) feeding punctures and one hatched egg mass and (5) plants bearing only an egg mass. In the case of plants with feeding punctures or feeding punctures plus an egg mass, the volatiles were also collected at different time intervals after plants were subjected to these two treatments (0-24 h, 24-48 h and 48-72 h). Gas chromatographic and gas chromatograph-mass spectrometric analysis showed that the percent emission of several compounds changed significantly from plants subjected to the feeding and oviposition or just oviposition. Percentage of terpenes generally decreased after feeding and oviposition, although the percentage emission of (E)-β-caryophyllene from these plants and those with just feeding punctures significantly increased. Plants with just an egg mass emitted linalool de novo but not (E)-β-ocimene. The emission of jasmonates, mainly methyl jasmonate, increased from plants with feeding punctures plus an egg mass compared to those with only an egg mass. Higher percentages of the volatile glucosinolate derivatives (VGSs), mainly 4-methoxy-3-indolylacetonitrile, were emitted by plants with feeding punctures and an egg mass. The percentage emission of most of these compounds increased during the first 24 h after the treatment and then decreased over the next 24 h, except for methyl jasmonate, which remained high also 48-72 h later. The possible ecological roles of such volatiles in plant interactions with the second and third trophic levels are discussed. |
Revision of Iberian species of the genus Merodon (Diptera: Syrphidae)Maria Angeles MARCOS-GARCÍA, Ante VUJIÆ, Ximo MENGUALEur. J. Entomol. 104 (3): 531-572, 2007 | DOI: 10.14411/eje.2007.073 This study is a revision of the Iberian Merodon Meigen, 1803 species, including an illustrated key, a discussion of taxonomic characters and a morphological diagnosis for all included species. Descriptions are provided for nine new species: M. antonioi sp. n., M. arundanus sp. n., M. cabanerensis sp. n., M. crypticus sp. n., M. hurkmansi sp. n., M. legionensis sp. n., M. longispinus sp. n., M. luteihumerus sp. n. and M. quercetorum sp. n. The taxon M. escorialensis Strobl, 1909 is redescribed and lectotype is designated. Lectotypes are designated for four taxa: M. albifrons Meigen, 1822; M. spinipes obscuritarsis Strobl in Czerny & Strobl, 1909; M. spicatus Becker, 1907; and M. spinipes grossus Gil Collado, 1930. Three varieties are redefined and considered as valid species: M. obscuritarsis Strobl in Czerny & Strobl, 1909 (as var. of spinipes); M. grossus Gil Collado, 1930 (as var. of spinipes); M. unicolor Strobl in Czerny & Strobl, 1909 (as var. of aeneus). The following new synonymies are proposed: M. affinis Gil Collado, 1930 syn.n. (= junior synonym of M. longicornis Sack, 1913); M. lusitanicus Hurkmans, 1993 syn.n. (= junior synonym of M. serrulatus Wiedemann in Meigen, 1822); M. andalusiacus Paramonov, 1929 syn.n., M. bolivari Gil Collado, 1930 syn.n., M. hispanicus Sack, 1931 syn.n. (= all three are junior synonyms of M. unguicornis Strobl in Czerny & Strobl, 1909); M. spicatus Becker, 1907 syn.n. (= junior synonym of M. chalybeus Wiedemann in Meigen, 1822); M. fuerteventurensis Barkemeyer, 2002 syn. n. (= junior synonym of M. obscuritarsis Strobl, 1909); and M. spinipes grossus (Gil Collado, 1930) syn.n. (= junior synonym of M. albifrons Meigen, 1822). Status of M. serrulatus Wiedemann in Meigen, 1822 is revised. Four species: M. longicornis Sack, 1913, M. pumilus Macquart, 1849, M. ottomanus Hurkmans, 1993 and M. segetum (Fabricius, 1794) are new for the Iberian Peninsula. Male genitalia are illustrated for all the species and a key of the 34 Iberian species (+ M. hurkmansi sp. n.) for males and females (except for the unknown female of M. longispinus sp. n.) is appended. Distribution and biological data for the Iberian species are also included. A brief zoogeographic discussion is also presented. The level of endemism of genus Merodon on the Iberian Peninsula is extremely high (almost 50%). |
Activity of Lygus lineolaris (Heteroptera: Miridae) adults monitored around the periphery and inside a commercial vineyardDominique FLEURY, Yves MAUFFETTE, Steve METHOT, Charles VINCENTEur. J. Entomol. 107 (4): 527-534, 2010 | DOI: 10.14411/eje.2010.060 The tarnished plant bug, Lygus lineolaris (Heteroptera: Miridae), is a highly polyphagous pest that feeds on a broad range of economically important crops in North America. Flying L. lineolaris adults can move from crop to crop rapidly and easily. Little is known about the movement of L. lineolaris in or near vineyards. From May to October 2002 and 2003, 39 white sticky traps were positioned inside and at the periphery of a vineyard to study the movements of tarnished plant bug adults. Tarnished plant bug captures were most numerous from the end of July to mid August, with captures of ca. 3000 individuals in one week. During the vegetative season, most individuals were captured flying in and around the vineyard at a height of between 40 and 60 cm. The frequency with which the weeds were mown affected the numbers of adults captured. At the periphery of the vineyard, tarnished plant bug was more abundant near perennial vegetation, which tends to be stable (an apple orchard, a spruce wood), than in the vineyard where agronomic activities changed the availability of food. The tarnished plant bug adults did not hibernate in the vineyard. It is suggested that appropriate weed management will reduce the abundance of tarnished plant bugs in vineyards as it would deprive them of a number of suitable hosts for feeding and oviposition. |
The effect of host plant and isolation on the genetic structure of phytophagous insects: A preliminary study on a bruchid beetleGwendal RESTOUX, Martine HOSSAERT-MCKEY, Betty BENREY, Nadir ALVAREZEur. J. Entomol. 107 (3): 299-304, 2010 | DOI: 10.14411/eje.2010.038 Genetic differentiation is a consequence of the combination of drift and restriction in gene flow between populations due to barriers to dispersal, or selection against individuals resulting from inter-population matings. In phytophagous insects, local adaptation to different kinds of host plants can sometimes lead to reproductive isolation and thus to genetic structuring, or even to speciation. Acanthoscelides obtectus Say is a bean bruchid specialized on beans of the Phaseolus vulgaris group, attacking both wild and domesticated forms of P. vulgaris and P. coccineus. This study reveals that the genetic structure of populations of this bruchid is explained mainly by their geographical location and is not related to a particular kind (wild or domesticated) of bean. In contrast, the species of bean might have led, to some extent, to genetic structuring in these bruchids, although our sampling is too limited to address such process unambiguously. If confirmed, it would corroborate preliminary results found for the parasitoid species that attack Acanthoscelides species, which might show a genetic structure depending on the species of host plant. |
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. |
Sociality improves larval growth in the stag beetle Figulus binodulus (Coleoptera: Lucanidae)Hideaki MORI, Satoshi CHIBAEur. J. Entomol. 106 (3): 379-383, 2009 | DOI: 10.14411/eje.2009.048 The benefits for offspring of attendant adult were investigated in the stag beetle Figulus binodulus. The initial growth rate of third-instar larva was significantly higher when the larvae were in a nest with adults compared to those in a nest without adults. The difference in growth rate is reflected in adult body size. Although the presence of adult beetle generally benefited the offspring, the adults did eat some of the larvae. Filial cannibalism was the primary cause of juvenile death in nests with adults. Mortality was lower in nests with adults related to the juveniles compared to nests with unrelated adults, suggesting that infanticide of nest mates may be inhibited. These results suggest that F. binodulus has a level of sociality and nest mate recognition that is very rare in stag beetles. Social behaviour may be more advantageous for small stag beetles than fighting. |
Studies on the identity of the parasitoids Aphidius colemani and Aphidius transcaspicus (Hymenoptera: Braconidae)Nikolaos GARANTONAKIS, Dionyssios PERDIKIS, Dionyssios LYKOURESSIS, Anna KOURTI, Theodoros GKOUVITSASEur. J. Entomol. 106 (4): 491-498, 2009 | DOI: 10.14411/eje.2009.062 The taxonomic status of the aphid parasitoid Aphidius colemani Viereck has been questioned, especially in regard to Aphidius transcaspicus Telenga (Hymenoptera: Braconidae). The genetic association between A. colemani and A. transcaspicus was studied by cross mating individuals of A. colemani and A. transcaspicus (A.c.& × A.t.% and A.c.% × A.t.&) and applying appropriate molecular methods. The cross mating resulted in offspring (female and males) that were fertile. Therefore, the cross mating assays performed in an artificial environment showed that these two populations are potentially compatible. The mean number of mummies that developed and the sex ratio of the offspring of each cross were similar. Most of the male and female offspring from each cross were assigned to A. transcaspicus. Furthermore, the genetic divergence between the ribosomal internal transcribed spacers (ITS2) of the A. colemani and A. transcaspicus studied was 16%. These results indicate that A. colemani might be a complex of species with different morphological and biological characters attacking different host aphids. |
The classification of insect communities: Lessons from orthopteran assemblages of semi-dry calcareous grasslands in central GermanyDominik PONIATOWSKI, Thomas FARTMANNEur. J. Entomol. 105 (4): 659-671, 2008 Whereas the classification of plant communities has a long tradition that of animal assemblages remains poorly developed. Here we propose a classification scheme for orthopteran communities based on regional "character species", "differential species" and "attendant species" at different levels of habitat complexity, which is also applicable to other insect groups. In this context there are three main points of special importance: (i) the geographical reference area, (ii) the hierarchical spatial level (e.g. habitat complex, habitat and microhabitat) and (iii) precise constancy criteria for the definition of character species and differential species. We develop this new approach using a study on orthopteran communites of central German semi-dry calcareous grasslands. Within this habitat, we describe seven structural types that are characterized by specific orthopteran communities. For the arrangement of the structural types several environmental parameters (e.g. height and density of vegetation) were collected. Orthopteran densities were sampled at 80 sites using a biocoenometer (box quadrat). Regional character species of semi-dry grasslands include Myrmeleotettix maculatus, Metrioptera brachyptera, Stenobothrus lineatus and Tetrix tenuicornis. Within this habitat, Chorthippus parallelus, Metrioptera roeselii, Omocestus viridulus, Pholidoptera griseoaptera and Tettigonia viridissima were designated as differential species for particular structural types. Furthermore, Tettigonia cantans and Tettigonia viridissima act as altitudinal differential species. Chorthippus biguttulus is the only attendant species with high constancy values in all structural types. This classification is a powerful tool for arthropod conservation, since it allows one to determine community completeness of very important and threatened habitats, like semi-dry calcareous grasslands. |
Effect of population density on the development of Mesovelia furcata (Mesoveliidae), Microvelia reticulata and Velia caprai (Veliidae) (Heteroptera: Gerromorpha)Tomá¹ DITRICH, Miroslav PAPÁÈEKEur. 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. |
No genetic differentiation in the rose-infesting fruit flies Rhagoletis alternata and Carpomya schineri (Diptera: Tephritidae) across central EuropeAnnette KOHNEN, Volker WISSEMANN, Roland BRANDLEur. J. Entomol. 106 (2): 315-321, 2009 | DOI: 10.14411/eje.2009.037 After the last glacial retreat in Europe, multiple recolonizations led to intraspecific differentiation in many of the recolonizing taxa. Here we investigate the genetic diversification across central Europe in two recolonizing taxa, the tephritid fruit flies Rhagoletis alternata (Fallén, 1814) and Carpomya schineri (Loew, 1856), which attack rose hips. Analysis of amplified and sequenced fragments of the mitochondrial genes encoding cytochrome oxidase I (800 bp), cytochrome oxidase II (470 bp) and cytochrome b (450 bp), indicate that all the individuals of R. alternata (n = 21) collected from across Europe share the same haplotype. Two individuals of C. schineri form Berlin, which is further north of the range than previously reported in the literature, differ from the other individuals (n = 13) in one nucleotide position on the cytochrome oxidase II gene fragment. This level of genetic variation in sequences with a summed length of 1720 bp is unexpectedly lower than in other insect taxa (n = 63). This might have been caused by a selective sweep by a cytoplasmic symbiont such as Wolbachia, or a recent range expansion associated with a host shift or a single recolonization event. |
INTERNATIONAL SYMPOSIUME.W. Evans, I. Hodek, N.G. Kavallieratos, E. Lucas, M. Mackauer, J.P. MichaudEur. J. Entomol. 105 (3): 365-368, 2008 | DOI: 10.14411/eje.2008.046 INTERNATIONAL SYMPOSIUM ECOLOGY OF APHIDOPHAGA 10, Athens, September 2007 Organized by the Benaki Phytopathological Institute, Kifissia, Attica, and the Agricultural University of Athens |
Revision of the subgenus Lampetis (Spinthoptera) (Coleoptera: Buprestidae) of North and Central America, and the West IndiesAngélica M. CORONAEur. J. Entomol. 102 (4): 737-776, 2005 The species of Lampetis (Spinthoptera) Casey, 1909 of Central America, North America and the West Indies are revised and 31 species are recognized. Six species from the West Indies [L. aurata (Saunders, 1871), L. aurifera (Olivier, 1790), L. bahamica (Fisher, 1925), L. guildini (Laporte & Gory, 1836), L. straba (Chevrolat, 1867), and L. torquata (Dalman, 1823)], eight species from Mexico [L. auropunctata (Kerremans, 1893) (new record for the USA), L. chalconota (Waterhouse, 1882), L. christophi Théry, 1923, L. dilaticollis (Waterhouse, 1882), L. geniculata (Waterhouse, 1889), L. granulifera (Laporte & Gory, 1837), L. mexicana Théry, 1923, and L. obscura Thomson, 1879], three species from Mexico and Central America [L. cortesi (Laporte & Gory, 1837), L. monilis (Chevrolat, 1834), L. simplex (Waterhouse, 1882)], and three from Central America [L. hirtomaculata (Herbst, 1801) = L. insularis (Casey, 1909) syn. n.; L. lesnei (Kerremans, 1910); and L. srdinkoana (Obenberger, 1924)] are redescribed. Seven new species (L. chamela sp. n., L. colima sp. n., L. cyanitarsis sp. n., L. hondurensis sp. n., L. tigrina sp. n., L. viridicolor sp. n., and L. viridimarginalis sp. n.) are described. Three species from Mexico and the United States [L. cupreopunctata (Schaeffer, 1905), L. drummondi (Laporte & Gory, 1836), and L. webbii (LeConte, 1858)], and one species from Mexico (L. chiapaneca Corona, 2004) are not described here, because they were (re)described recently. The diagnosis, distribution, host plants and phenology data of L. chiapaneca, L. cupreopunctata, L. drummondi, and L. webbii are given. Lampetis famula Chevrolat, 1838 and L. variolosa (Fabricius, 1801) are not recognized herein as Mexican species, because they are from South America according to the literature and specimens studied. Information on variation, distribution, and host plants are given for each species. Photographs of dorsal habitus and male genitalia are included. |
Heartbeat reversal after sectioning the dorsal vessel and removal of the brain of diapausing pupae of Manduca sexta (Lepidoptera: Sphingidae)Karel SLÁMAEur. J. Entomol. 103 (1): 17-26, 2006 | DOI: 10.14411/eje.2006.003 Reversal of heartbeat was monitored in vivo by noninvasive, multisensor, thermo-cardiographic and pulse-light, opto-cardiographic techniques. The dorsal vessel was sectioned at the beginning, in the middle and near the end of the abdomen. Changes in the heartbeat were simultaneously monitored in both the disconnected anterior and posterior sections of the heart. The results revealed the existence of a caudal regulatory cardiac centre located in the fused A7-A10 abdominal segments. Posterior sections, containing this terminal ampulla of the heart always exhibited a more or less normal heartbeat reversal, including both anterograde and retrograde pulsations. This shows that the forward-oriented as well as the reciprocal, backward-oriented peristaltic waves of the heart are both regulated from the posterior regulatory center, without involvement of the cephalic region. The cardiac pulsations in the anterior sections of the heart were paralysed and seriously impaired by the lesions. During the acute phase after the lesions, anterior sections showed only some convulsion-like, unidirectional, backward-oriented peristaltic pulsations of low frequency. Within one or two days after the lesions, isolated anterior sections of the heart developed a subsidiary heartbeat regulation associated with the oscillating, bi-directional peristaltic waves running alternatively, forward and backward in opposite directions. |
Effect of temperature on the life history of Encarsia bimaculata (Hymenoptera: Aphelinidae), a parasitoid of Bemisia tabaci (Hemiptera: Aleyrodidae)Bao-Li QIU, Paul J. DE BARRO, Cai-Xia XU, Shun-Xiang RENEur. J. Entomol. 103 (4): 787-792, 2006 | DOI: 10.14411/eje.2006.107
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The effect of environmental conditions on diapause in the blister beetle, Mylabris phalerata (Coleoptera: Meloidae)Fen ZHU, Fangsen XUE, Chaoliang LEIEur. J. Entomol. 103 (3): 531-535, 2006 | DOI: 10.14411/eje.2006.069 In the field, the blister beetle Mylabris phalerata Pallas (Coleoptera: Meloidae) undergoes larval diapause in the ground, which lasts for nearly six months. The effect of the soil environment on this diapause was examined. Final instar larvae kept at temperatures of >= 26°C do not enter diapause and continued to develop regardless of the soil water content and photoperiod. Below 25°C the final instar larvae entered diapause regardless of soil water content and photoperiod. The early stages, particularly L2, appeared to be more important for diapause induction than the later stages. However, the other instars were also sensitive. Temperature, rather then photoperiod was the main factor influencing pupal duration. |
Proceedings of the International Symposium Ecology of AphidophagaEdward Evans, Francis Gilbert, Ivo Hodek, J.P. Michaud, John ObryckiEur. J. Entomol. 102 (3): 313-315, 2005 | DOI: 10.14411/eje.2005.048 This series of symposia has traditionally been a unique scientific forum for discussions on ecological and behavioural interactions within the guild of insects feeding on aphids. Its focus is to understand how natural control works, with the aim to improve it. After the initial two meetings in Czechoslovakia, symposia were organised in Poland, Hungary, France, Belgium, Canada and Portugal. The ninth meeting was held once again in the Czech Republic. |
Community structure and reproductive biology of bark beetles (Coleoptera: Scolytinae) associated with Macaronesian Euphorbia shrubsBjarte H. JORDALEur. J. Entomol. 103 (1): 71-80, 2006 | DOI: 10.14411/eje.2006.012 Dead wood of arborescent Euphorbia plants in the Macaronesian islands and Morocco has a diverse fauna of wood-boring beetles. Thirty-eight species were found in four species groups of Euphorbia, including 29 species of scolytine bark beetles, six species of cossonine weevils, two species of Laemophloeidae and one of Monotomidae. All scolytines (but not cossonines and cucujoids) have narrow host preferences, using only one host group for feeding and reproduction. The number of islands on which each species was found was also limited, resulting in geographically distinct guilds for each Euphorbia host. The majority of species (26) were found on the E. lamarckii species complex, followed by E. balsamifera (13) and the succulents E. canariense (12) and E. echinus (3), while only two species were found on the rare montane species, E. longifolia, in Madeira. Up to six or seven species could be found in a single branch of E. lamarckii and E. canariense, respectively, but more than half of the plants had fewer than three species. Putative niche partitioning was indicated by the alternative utilization of different tissues in E. balsamifera and different moisture preferences in the succulent E. canariense. Several unusual features of bark beetle reproductive biology were also observed, including infrequent communal nesting and very small broods. Taken together with the phylogenetic, geographical and biological data now available for most species associated with dead Euphorbia, several of the beetle guilds should provide promising model systems for studying of species interactions and community structure. |
Variability in the karyotypes, testes and ovaries of planthoppers of the families Issidae, Caliscelidae, and Acanaloniidae (Hemiptera: Fulgoroidea)Anna MARYAÑSKA-NADACHOWSKA, Valentina G. KUZNETSOVA, Vladimir M. GNEZDILOV, Sakis DROSOPOULOSEur. J. Entomol. 103 (3): 505-513, 2006 | DOI: 10.14411/eje.2006.066 The aim of this study was to obtain information on the karyotypes, testes and ovaries of three fulgoroid families, mainly in the Issidae but also in the Caliscelidae and Acanaloniidae. For the Issidae, the data is for 19 species belonging to 11 genera of the subtribes Issina (2 species, 1 genus), Hysteropterina (14 species, 9 genera) and Agalmatiina (3 species, 2 genera) of the tribe Issini. The male karyotypes are shown to be quite uniform across the tribe, with 2n = 26 + X in all species studied except Latilica maculipes (Melichar, 1906) with 2n = 24 + X. The modal karyotype, 2n = 26 + X, matches the most probable ancestral state in the Fulgoroidea. In the majority of cases the number of seminal follicles in males and ovarioles in females are stable within but fairly variable among the species, the modal value of the follicle number is 10 per testis. Contrary to what might be expected from other fulgoroid families, such as the Dictyopharidae and Delphacidae, the variability in these characters revealed neither regular trends nor evident correspondence with the taxonomy of Issidae. In the Caliscelidae, all species studied had testes consisting of 6 follicles each and karyotypes of 2n = 24 + X and 26 + XY, respectively, in 3 and 1 species. The only representative studied of the Acanaloniidae, Acanalonia bivittata (Say, 1825), had 2n = 24 + X and 13 follicles in its testis. The variability in all the characters investigated is discussed and compared to other fulgoroid families, primarily to the most extensively studied families, Delphacidae and Dictyopharidae. |
Karyotype and male meiosis in Spartocera batatas and meiotic behaviour of multiple sex chromosomes in Coreidae (Heteroptera)María José FRANCO, María José BRESSA, Alba GRACIELA PAPESCHIEur. J. Entomol. 103 (1): 9-16, 2006 | DOI: 10.14411/eje.2006.002 The Coreidae (Heteroptera) have holokinetic chromosomes and during male meiosis the autosomal bivalents segregate reductionally at anaphase I while the sex chromosomes do so equationally. The modal diploid chromosome number of the family is 2n = 21, with a pair of m-chromosomes and an X0/XX sex chromosome system. A 2n = 24/26 (male/female) and an X1X20/X1X1X2X2 sex chromosome system were found in Spartocera batatas (Fabricius). C-banding and fluorescent-banding revealed the presence of AT-rich heterochromatic bands medially located on all the autosomes, and one telomeric band on both the X1 and X2 chromosomes. This banding pattern differed from the telomeric heterochromatin distribution found in most other heteropteran species. The X1 and X2 chromosomes were intimately associated during male meiosis and difficult to recognize as two separate entities. Based on a comparison with the behaviour of sex chromosomes in other coreids and other heteopterans with multiple sex chromosomes it is suggested that the particular behaviour of X1 and X2 chromosomes in coreid species with multiple sex chromosome systems evolved as an alternative mechanism for ensuring the proper segregation of the sex chromosomes during meiosis. |
Egg-dumping behaviour in the seed beetle Acanthoscelides obtectus (Coleoptera: Chrysomelidae: Bruchinae) selected for early and late reproductionDarka ©E©LIJA, Biljana STOJKOVIÆ, Branka TUCIÆ, Nikola TUCIÆEur. J. Entomol. 106 (4): 557-563, 2009 | DOI: 10.14411/eje.2009.070 In the present study the egg dumping behaviour in short (E)- and long (L)-lived lines of the seed beetle Acanthoscelides obtectus was analyzed. Females of the short-lived E line exhibited substantially higher egg dumping than long-lived L line females. We hypothesize that, since cessation of egg dumping enhances longevity, non-dumping females were selectively favoured in the L regime. Our study also produced evidence that the selection regime affected the male's ability to influence female egg-dumping behaviour. The females mated to males from the lines that were selected for extended longevity and of which the females exhibited little egg-dumping dumped fewer eggs. We suggest that in the L selection regime, where offspring produced at the end of the females' reproductive period were recruited to the next generation, selection operated against those males that stimulated female oviposition in the absence of seeds. This is the first study to provide evidence that selection for long-lived insects results in the reduced potency of male seminal products to stimulate female oviposition. |
Spatial population structure of the predatory ground beetle Carabus yaconinus (Coleoptera: Carabidae) in the mixed farmland-woodland satoyama landscape of JapanYoshitake KAGAWA, Kaoru MAETOEur. J. Entomol. 106 (3): 385-391, 2009 | DOI: 10.14411/eje.2009.049 To conserve the predators and parasitoids of agricultural pests it is necessary to understand their population structure in a mixed landscape, and to consider the spatial and temporal changes in their distribution and movement of adults and larvae. We studied the distribution and movement of the ground beetle Carabus yaconinus (Coleoptera: Carabidae), which inhabits farmland-woodland landscapes. We placed a large number of pitfall traps along the border between a wood and an orchard and counted the number of C. yaconinus adults and larvae caught in the traps from 13 April to 28 June 2005. Some of the adults were marked before they were released. Adults were most abundant at the edge of the wood and the number caught gradually decreased when entering into the wood. In contrast, larvae were only found in the interior of the wood, although they moved closer to the edge of the wood as they matured. Adult females were collected within the wood and neighbouring orchards more frequently than adult males. It is likely that females enter woodlands in search of oviposition sites and leave woodlands in search of high-protein food sources to support reproduction. For sustaining populations of C. yaconinus it is necessary to have woodlands of at least 60 m in width adjacent to farmland. It is possible to design an appropriate landscape if the habitat requirements of the predatory arthropods are well understood. |
Phylogenetic revision of the New Zealand genus Dasytricheta, with a discussion of its systematic position within the subfamily Aleocharinae (Coleoptera: Staphylinidae)Grzegorz PA¦NIKEur. J. Entomol. 104 (4): 815-826, 2007 | DOI: 10.14411/eje.2007.102 The genus Dasytricheta Bernhauer, 1943 is redefined. The genus Pyromecroma Cameron, 1945 is considered a new synonym of Dasytricheta. Eleven valid species are recognised in the genus: Dasytricheta spectabilis Bernhauer, 1943 (the type species of Dasytricheta), D. funesta (Broun, 1912) comb. n. (the type species of Pyromecroma, originally described in Myrmecopora Saulcy, 1864), and nine species described as new: Dasytricheta haastiana sp. n., D. hookeriana sp. n., D. intermedia sp. n., D. kapuniana sp. n., D. mahitahiana sp. n., D. periana sp. n., D. shotoveriana sp. n., D. testacea sp. n. and D. waihoana sp. n. The taxa are diagnosed, keyed and illustrated. The phylogeny of Dasytricheta is analysed using cladistic methods. The systematic position of Dasytricheta within the Aleocharinae is discussed. |
Phosphorylation of small GTPase Rab proteins from Bombyx mori (Lepidoptera: Bombycidae)Tomohide UNO, Keisuke HATA, Dieu Trang LE THI, Susumu HIRAGAKI, Takuya NAKADA, Masahiko NAKAMURA, Yuichi UNO, Hiroshi YAMAGATA, Kengo KANAMARU, Makio TAKEDA, Mamoru MATSUBARAEur. J. Entomol. 106 (4): 499-506, 2009 | DOI: 10.14411/eje.2009.063 Small GTPases of the Rab family act as essential regulators of vesicle transport pathways. Five Rab cDNA clones (BRab1, 7, 8, 11 and 14) from Bombyx mori were expressed in Escherichia coli as a thioredxin or glutathione sulfotransferase fusion protein. After purification, the fusion protein was tested for phosphorylation using protein kinase C (PKC). Results indicate that all of them were phosphorylated in vitro. The phosphorylation site of BRab1 was determined by mass-spectrometric analysis, which identified that Ser-17 of BRab1 was phosphorylated by PKC. Deletion and site-directed mutagenesis indicated that Ser-111of BRab8, in addition to Ser-17, was newly phosphorylated. Further immunohistochemical analysis using antibodies against Rab8 indicated that there are some Rab8 immunoreactive cells close to the neuropeptide secreting cells. This result suggests that in insects Rab proteins are regulated by phosphorylation and at least some of them are involved in neuropeptide secretion. |
Aristolochic acids affect the feeding behaviour and development of Battus polydamas archidamas larvae (Lepidoptera: Papilionidae: Troidini)Carlos F. PINTO, Alejandra J. TRONCOSO, Alejandro URZÚA, Hermann M. NIEMEYEREur. J. Entomol. 106 (3): 357-361, 2009 | DOI: 10.14411/eje.2009.044 The feeding behaviour of specialist butterflies may be affected by the mechanical and chemical characteristics of the tissues of their host-plants. Larvae of the butterfly, Battus polydamas archidamas feed only on Aristolochia chilensis, which contains aristolochic acids. We studied the oviposition pattern of adults and the foraging of larvae of B. polydamas archidamas over time in relation to variations in hardness of the substrate and concentration of aristolochic acids in different plant tissues. We further tested the effect of two artificial diets containing different concentrations of aristolochic acids on larval performance. B. polydamas archidamas oviposited mostly on young leaves and the larvae fed on this tissue until the second instar. Third instar larvae fed also on mature leaves and fourth and higher instars fed also on stems. Young leaves are softer and contain higher concentrations of aristolochic acids than mature leaves, and stems are both harder and contain a high concentration of aristolochic acids. Larvae reared on artificial diets containing a high concentration of aristolochic acids suffered less mortality and were heavier than those reared on a diet with a lower concentration of aristolochic acids, which suggests they are phagostimulatory. A strategy of host use regulated by aristolochic acid content and tissue hardness is discussed. |
Life tables and demographic statistics of Russian wheat aphid (Hemiptera: Aphididae) reared at different temperatures and on different host plant growth stagesZhanshan (Sam) MA, Edward J. BECHINSKIEur. J. Entomol. 106 (2): 205-210, 2009 | DOI: 10.14411/eje.2009.026 Laboratory experiments were used to investigate the influences of 25 combinations of temperature and barley plant growth stage (5 × 5 factorial combination of temperature and barley plant growth stage) on the development, survival and reproduction of the Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko). For each of the 25 treatments, the developmental time and nymphal production of 72 RWA individuals were recorded (1800 RWA in total) throughout their entire lifetimes. The collected data were used for analyzing demography, modelling phenology, and simulating population growth of RWA. In this paper, the results of demographic analyses are reported. Specifically, for each treatment, cohort life tables, reproductive heterogeneity tables (parity and birth intervals), and reproductive schedule tables were constructed, and demographic parameters such as intrinsic rate of increase, life-span, fecundity, life table entropy, etc. calculated. Based on these analyses, the most important summary demographic statistics are reported. Using the intrinsic rate of increase (rm) as an example, a procedure is demonstrated that builds a dynamic rm model by applying the Best Subset Regression approach. A more comprehensive (considering reproductive heterogeneity and schedule tables) yet concise (comprising dynamic rm models) demographic model than that based on standard life table analysis alone is presented. |
Use of volatiles of Aristolochia chilensis (Aristolochiaceae) in host searching by fourth-instar larvae and adults of Battus polydamas archidamas (Lepidoptera: Papilionidae: Troidini)Carlos F. PINTO, Alejandra J. TRONCOSO, Alejandro URZÚA, Hermann M. NIEMEYEREur. J. Entomol. 106 (1): 63-68, 2009 | DOI: 10.14411/eje.2009.010 Papilionid butterflies of the tribe Troidini are specialists on plants of the family Aristolochiaceae. The role of plant volatiles in host recognition by adult and larval stages of these insects remains unknown. We used Battus polydamas archidamas (Papilionidae: Troidini) and its host-plant, Aristolochia chilensis (Aristolochiaceae), to study: (i) the olfactory and electrophysiological responses of adults to headspace volatiles of the host-plant, (ii) the chemical composition of the headspace volatiles of the host-plant, (iii) the patterns of aggregation of larvae in the field in order to ascertain the time when they leave the plant where the eggs were laid, and (iv) the olfactory responses of solitary-feeding fourth-instar larvae to headspace volatiles of the host-plant. Larvae left their initial host-plant during the third or fourth instar. Host-plant headspace volatiles attracted fourth-instar larvae as well as adults; adult females were more responsive than males. Taken together, these results reveal changes in the responsiveness to host-plant volatiles during development, and provide an insight into the host-plant specialization of this butterfly. |
Taxonomy of the genus Amphiareus (Heteroptera: Anthocoridae) in Southeast AsiaKazutaka YAMADAEur. J. Entomol. 105 (5): 909-916, 2008 | DOI: 10.14411/eje.2008.118 Four species of the genus Amphiareus are recognized in southeastern Asia, including two new species, A. edentulus and A. rompinus, both from Johor, Malaysia. The two known species, A. constrictus (Stål) and A. ruficollaris Yamada & Hirowatari are also diagnosed and figured; the latter is recorded from this region for the first time. The genus is diagnosed and briefly discussed. |
Male territorial behaviour of the endemic large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis (Hymenoptera: Apidae), on the oceanic Ogasawara IslandsShinji SUGIURAEur. J. Entomol. 105 (1): 153-157, 2008 | DOI: 10.14411/eje.2008.021 The endemic large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis Matsumura (Hymenoptera: Apidae), on the oceanic Ogasawara (Bonin) Islands, located in the northwestern Pacific Ocean, approximately 1000 km south of the Japanese mainland, is a generalist flower visitor. Although the flower-visiting behaviour of X. ogasawarensis females has been frequently recorded, the behaviour of the males in this species has rarely been studied. I observed the territorial behaviour of males on flowers of the native plant species Scaevola sericea Vahl (Campanulales: Goodeniaceae) in a coastal area of Hahajima in early July 2007. Each male chose a particular inflorescence, hovered near it (mean distance, 239 mm from the inflorescence) and patrolled around it for several minutes (mean time, 331 s). Therefore, X. ogasawarensis males exhibit resource-based (i.e., flowers) territoriality. Males frequently attacked other males when defending their territories. However, males did not defend their territories against flower visitors of other species (i.e., introduced honeybees). Therefore, male territorial behaviour in X. ogasawarensis may be related to intrasexual competition for sites visited by females. This is the first report describing the male territorial behaviour of X. ogasawarensis. |
BOOK REVIEW: Van Driesche R., Hoddle M. & Center T.: Control of Pests and Weeds by Natural Enemies. An Introduction to Biological Control.I. HODEKEur. J. Entomol. 106 (2): 323, 2009 | DOI: 10.14411/eje.2009.038 Blackwell, Malden, MA & Oxford, 2008, 473 pp. ISBN 978-1-4051-4571-8. Price: USD 69.95. |
Brood attending by females of the hyperparasitoid Trichomalopsis apanteloctena (Hymenoptera: Pteromalidae) on cocoon clusters of its host, Cotesia kariyai (Hymenoptera: Braconidae) and its effects on reproduction, development and survivalNaoto TAKAI, Yutaka NAKAMATSU, Jeffrey A. HARVEY, Ken MIURA, Toshiharu TANAKAEur. J. Entomol. 105 (5): 855-862, 2008 | DOI: 10.14411/eje.2008.113 Theoretical models predict that brood guarding may evolve in situations where eggs are costly to produce or when handling times are long. This study reveals that females of the secondary hyperparasitoid Trichomalopsis apanteloctena guarded cocoon broods of Cotesia kariyai, a gregarious endoparasitoid. Hyperparasitoid females also monopolized host resources and protected their offspring by driving away other conspecific hyperparasitoid females. The females exhibited antagonistic behavior towards competitors through threatening body postures, biting and chasing. Using a video camera to determine how long a hyperparasitoid female attended and parasitized cocoons within a single host brood, it was found that after about 4 days, cocoon guarding behavior became much less apparent. Moreover, more than 90% of hosts were typically parasitized by a hyperparasitoid female over the course of 4 days after she commenced brood guarding. Observations of egg production during a female's lifetime revealed a physiological interval rhythm that typically lasted 3-4 days, which correlates almost exactly with the period during which the cocoons were guarded. To confirm the giving-up time for a host cocoon brood, hyperparasitoid females were given access to 24 h-old cocoon clusters, each containing 60-100 individual cocoons. Ninety percent of the females remained on cocoons for approximately 72 h. Furthermore, twenty-five percent of wasps continued attending and presumably guarding host cocoon broods for more than 138 h after the female first attended the brood. C. kariyai larvae pupate within a few hours of egression from their host and emerge as adults about 5 days (120 h) later. Therefore, many hyperparasitoid females continued to guard older host cocoons of greatly reduced quality as a resource for their progeny and some even after eclosion of the primary parasitoid. Late-brood guarding enabled a hyperparasitoid female to protect her own progeny from other hyperparasitoid females that readily attacked and killed them when she was removed. Our study thus reveals that extended guarding behavior is an adaptive mechanism that probably plays an important role in the survival of the original brood. |



