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Results 1201 to 1230 of 1606:

Effects and interactions of temperature, host deprivation and adult feeding on the longevity of the parasitoid Venturia canescens (Hymenoptera: Ichneumonidae)

Panagiotis A. ELIOPOULOS, George J. STATHAS, Stelios L. BOURAS

Eur. J. Entomol. 102 (2): 181-187, 2005 | DOI: 10.14411/eje.2005.029

A laboratory study was carried out to determine the effects and interactions of temperature, host deprivation and adult feeding on the longevity of the parasitoid Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae). The effect of body size was also examined. Large wasps (hind tibia length > 1.96 mm) lived significantly longer than smaller conspecifics (hind tibia length < 1.89 mm). Adults reared at 15°C lived longer regardless of whether supplied with hosts or food. Correspondingly, adults had a shorter life at 30°C. Honey-fed adults lived significantly longer than starved adults at all temperatures and irrespective of host presence, while access to hosts resulted in a decrease in longevity at all temperatures, regardless of food supply. The Weibull distribution was used to describe the age specific survival, which in V. canescens is of "Type I", as the risk of death increases with age. Despite the significant effect of host presence on survival it was less than either temperature or feeding. The interactions between feeding, host presence and temperature proved to be significant. The objective of the study was to improve the effectiveness of V. canescens as a biological control agent of stored product pests.

Phytophagous insects of giant hogweed Heracleum mantegazzianum (Apiaceae) in invaded areas of Europe and in its native area of the Caucasus

Steen Ole HANSEN, Jan HATTENDORF, Ruediger WITTENBERG, Sergey Ya. REZNIK, Charlotte NIELSEN, Hans Peter RAVN, Wolfgang NENTWIG

Eur. J. Entomol. 103 (2): 387-395, 2006 | DOI: 10.14411/eje.2006.052

Giant hogweed, Heracleum mantegazzianum (Apiaceae), was introduced from the Caucasus into Western Europe more than 150 years ago and later became an invasive weed which created major problems for European authorities. Phytophagous insects were collected in the native range of the giant hogweed (Caucasus) and were compared to those found on plants in the invaded parts of Europe. The list of herbivores was compiled from surveys of 27 localities in nine countries during two seasons. In addition, literature records for herbivores were analysed for a total of 16 Heracleum species. We recorded a total of 265 herbivorous insects on Heracleum species and we analysed them to describe the herbivore assemblages, locate vacant niches, and identify the most host-specific herbivores on H. mantegazzianum. When combining our investigations with similar studies of herbivores on other invasive weeds, all studies show a higher proportion of specialist herbivores in the native habitats compared to the invaded areas, supporting the "enemy release hypothesis" (ERH). When analysing the relative size of the niches (measured as plant organ biomass), we found less herbivore species per biomass on the stem and roots, and more on the leaves (Fig. 5). Most herbivores were polyphagous generalists, some were found to be oligophagous (feeding within the same family of host plants) and a few had only Heracleum species as host plants (monophagous). None were known to feed exclusively on H. mantegazzianum. The oligophagous herbivores were restricted to a few taxonomic groups, especially within the Hemiptera, and were particularly abundant on this weed.

Seasonal occurrence, distribution and sampling indices for Myzus persicae (Hemiptera: Aphidoidea) and its parasitoids (Hymenoptera: Braconidae: Aphidiinae) on tobacco

Nickolas G. KAVALLIERATOS, Christos G. ATHANASSIOU, Željko TOMANOVIĆ, Andrea SCIARRETTA, Pasquale TREMATERRA, Vladimir ŽIKIĆ

Eur. J. Entomol. 102 (3): 459-468, 2005 | DOI: 10.14411/eje.2005.066

Field studies were conducted, in order to assess the seasonal occurrence and the spatial distribution of Aphidius colemani Viereck, Aphidius matricariae Haliday, Diaeretiella rapae (M'Intosh), Praon staryi Kavallieratos & Lykouressis and Praon volucre (Haliday), all parasitoids of Myzus persicae (Sulzer) on tobacco. The experiments took place in western Greece (Agrinion, Aitoloakarnania), during the 1996 and 1997 growing seasons, in an area of approximately 2.5 ha, where tobacco was the main crop. The experimental field was insecticide-free and tobacco leaf samples (from the upper and lower half of plants) were taken from June until September, in both years. The distribution of the species found was also represented and discussed. Generally, high M. persicae densities were recorded in August (mid-season) of both seasons. The mummification rate showed a specific increasing trend late in the season (August-September). In 1996, the percentage of mummification reached almost 61% at the end of the period, whereas in 1997 it remained at very low levels (<2%). The density of M. persicae was higher on the leaves collected from the upper part of the plants than on those from the lower part, but without significant difference. In contrast, the numbers of mummified M. persicae individuals were significantly higher on leaves collected from the lower part of the plants than on those from the upper part in both years. The relative abundance of the aphidiine parasitoid species differed between the two years.

Hedyselmis opis: Description of the larva and its phylogenetic relation to Graphelmis (Coleoptera: Elmidae: Elminae)

Fedor ČIAMPOR Jr., Ignacio RIBERA

Eur. 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.

Effect of temperature on some biological parameters of an Iranian population of the Rose Aphid, Macrosiphum rosae (Hemiptera: Aphididae)

Mohsen MEHRPARVAR, Bijan HATAMI

Eur. J. Entomol. 104 (3): 631-634, 2007 | DOI: 10.14411/eje.2007.078

The rose aphid, Macrosiphum rosae, living on rose var. Black Magic, was reared in the laboratory at four constant temperatures 15, 18, 22 and 25 ± 1°C, 75 ± 5% R.H. and 14L : 10D. Parameters investigated included developmental rate, survival, pre-reproductive delay and fecundity. The rate of nymphal development (0.17) was greatest at 22°C. The longest developmental time (12.33 days) was recorded at 15°C. The generation time was longest and shortest at 15°C and 22°C respectively. The lower developmental threshold was calculated to be 9.05°C. Based on this, the degree-day requirement from birth to adulthood was found to be 77.5 dd. The pre-reproductive delay also decreased markedly with increase in temperature from 15°C to 22°C. The longest lifespan of apterous females (12.38 d) was observed at 15°C, whereas the shortest (8.06 d) was at 25°C. The mean adult longevity declined with increase in temperature from 15°C to 25°C. The fecundity of females (progeny/female) increased from 11.38 to 28.88 with increase in temperature from 15°C to 22°C but then decreased to 8.38 as the temperature increased from 22°C to 25°C. The largest (0.311) and smallest (0.113) rm occurred at 22°C and 15°C respectively. All of the parameters of the M. rosae life cycle at the four temperatures tested were optimum at 22°C. This Iranian population of M. rosae can develop at lower temperatures than an Australian population.

The genus Amiota (Diptera: Drosophilidae) from Hengduan Mountains, southwestern China

Wenxia ZHANG, Hongwei CHEN

Eur. J. Entomol. 103 (2): 483-495, 2006 | DOI: 10.14411/eje.2006.062

A total of 39 Amiota species are found from the southern portion of Hengduan Mountains, southwestern China, including 12 new species: A. gaoi sp. n., A. gracilenta sp. n., A. multispinata sp. n., A. yifengi sp. n., A. angustifolia sp. n., A. bacillia sp. n., A. biacuta sp. n., A. cultella sp. n., A. deltoidea sp. n., A. pianmensis sp. n., A. setosa sp. n. and A. bifoliolata sp. n. A key to all the studied species from Hengduan Mountains is provided.

Redescriptions of Ordalonema faciepilosa, Peltonotellus melichari and P. raniformis, with a key to Western Palaearctic genera of Caliscelidae (Hemiptera: Fulgoromorpha)

Werner E. HOLZINGER

Eur. J. Entomol. 104 (2): 277-283, 2007 | DOI: 10.14411/eje.2007.042

First descriptions of males of Peltonotellus raniformis (Mulsant & Rey, 1855), P. melichari Horváth, 1897 and Ordalonema faciepilosa Dlabola, 1980 are given. In addition, identification keys to the eight Caliscelidae genera of the Western Palaearctic and to the five Peltonotellus Puton, 1886 species of Europe are presented.

Diapause development and cold hardiness of Pectinophora gossypiella (Lepidoptera: Gelechiidae) larvae in Greece

Olga P. KALTSA, Panagiotis G. MILONAS, Matilda SAVOPOULOU-SOULTANI

Eur. J. Entomol. 103 (3): 541-545, 2006 | DOI: 10.14411/eje.2006.072

Larval diapause development and termination and some characteristics of cold hardiness in Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) were studied under field conditions in northern Greece. P. gossypiella overwintering larvae were sampled at 20 to 30 day intervals and subjected to two photoperiodic regimes at 20°C. In larvae kept under a long-day photoperiod (16L : 8D) diapause development was accelerated compared to those kept under a short-day photoperiod (8L : 16D). There was no difference in response to the two photoperiods after February. Mean number of days to pupation of P. gossypiella overwintering larvae decreased progressively through the sampling period, from November to April. Chilling is not a prerequisite but does accelerate diapause development. Supercooling points for P. gossypiella overwintering larvae ranged from -14 to -17°C with the majority dying after freezing.

Myzocallis walshii (Hemiptera: Sternorrhyncha: Aphididae), an exotic invasive aphid on Quercus rubra, the American red oak: Its bionomy in the Czech Republic

Jan HAVELKA, Petr STARÝ

Eur. J. Entomol. 104 (3): 471-477, 2007 | DOI: 10.14411/eje.2007.067


Myzocallis
(Lineomyzocallis) walshii (Monell), a North American aphid species associated with Quercus rubra was detected for the first time in Europe in 1988 (France), and subsequently in several other countries - Switzerland, Spain, Andorra, Italy, Belgium and Germany. Recent research in 2003-2005 recorded this aphid occurring throughout the Czech Republic. The only host plant was Quercus rubra. The highest aphid populations occurred in old parks and road line groves in urban areas, whereas the populations in forests were low. The seasonal occurrence of the light spring form and the darker summer form of M. (Lineomyzocallis) walshii as well as their different population peaks were noted. Four native parasitoids species [Praon flavinode (Haliday), Trioxys curvicaudus Mackauer, T. pallidus Haliday and T. tenuicaudus (Starý)] were reared from M. (Lineomyzocallis) walshii.

Seasonal wing dimorphism and life cycle of the mole cricket Gryllotalpa orientalis (Orthoptera: Gryllotalpidae)

Chihiro ENDO

Eur. J. Entomol. 103 (4): 743-750, 2006 | DOI: 10.14411/eje.2006.098

Control of seasonal wing dimorphism in the oriental mole cricket Gryllotalpa orientalis Brumeister (1839) from a wetland habitat in western Japan is described. The long-winged (LW) morph appeared from mid-June to September, whereas the short-winged (SW) morph appeared from September to mid-June. Individuals overwintered in either the adult or juvenile stage. The seasonal shift in wing morphology was linked to the overwintering stage. Individuals that hatched in May became SW adults in September-October and then overwintered, whereas those that hatched in June and July overwintered as juveniles and became LW adults in June of the following year. The life cycle of both morphs was univoltine. Reproductive benefits and constraints of each wing morph of G. orientalis are compared.

Comparative study of larvae of Tenebrionoidea (Coleoptera: Cucujiformia)

Rolf Georg BEUTEL, Frank FRIEDRICH

Eur. J. Entomol. 102 (2): 241-264, 2005 | DOI: 10.14411/eje.2005.037

External and internal head structures and external structures of the thorax and abdomen of larval representatives of Melandryidae (Orchesia), Ulodidae (Meryx), Oedemeridae (Pseudolycus) and Pythidae (Pytho) are described. The obtained data were compared to characters of other tenebrionoid larvae and to larval characters of other representatives of Cucujiformia. Characters potentially relevant for phylogenetic reconstruction are listed and were analysed cladistically. The data set is characterised by a high degree of homoplasy and the resolution of the strict consensus trees of 2650 or 815 (second analysis) minimal length trees is low. The monophyly of Tenebrionoidea is supported by several larval autapomorphies, e.g. posteriorly diverging gula, anteriorly shifted posterior tentorial arms, asymmetric mandibles and the origin of several bundles of M. tentoriopharyngalis from the well-developed gular ridges. Several features of the larval head are plesiomorphic compared to the cleroid-cucujoid lineage. The interrelationships of most tenebrionoid families not belonging to the pythid-salpingid and anthicid-scraptiid groups were not resolved. Synchroidae were placed as sister group of a clade comprising these two lineages and Prostomidae. A sistergroup relationship between Trictenotomidae and Pythidae seems to be well supported and the monophyly of the anthicid-scraptiid lineage was also confirmed. Another potential clade comprises Prostomidae, Mycteridae and Boridae, and possibly Pyrochroidae (s.str.) and Inopeplinae. The monophyly of Salpingidae (incl. Othniinae and Inopelinae) and Pyrochroidae (incl. Pedilinae) was not supported. Many features such as the shape of the head and body, sutures and ridges of the head capsule, the endocarina, the mandibles, the maxillary apex, and also characters of the terminal abdominal apex are highly variable, even within families. Especially the families Tetratomidae, Melandryidae, Colydiidae and Zopheridae show a high degree of variation in the larval stages. Several taxa appear isolated in terms of larval morphology within the families they are assigned to, e.g. Orchesia within Melandryidae, Sphindocis (Sphindocinae) within Ciidae, Calopus (Calopinae) within Oedemeridae and Penthe (Penthinae) within Tetratomidae. A broader spectrum of characters and a stepwise approach will be needed for a reliable clarification of the relationships within a very complex group like Tenebrionoidea.

The composition of the arthropod fauna of the canopies of some species of oak (Quercus)

T. Richard E. SOUTHWOOD, G.R. William WINT, Catherine E.J. KENNEDY, Steve R. GREENWOOD

Eur. J. Entomol. 102 (1): 65-72, 2005 | DOI: 10.14411/eje.2005.009

1. A study was made by knockdown sampling and branch clipping of the arthropod fauna of the canopy of two native oak species (Quercus robur and Q. petraea) and of two introduced species (Q. cerris and Q. ilex ) in woods near Oxford, UK, and of two native species (Q. pubescens and Q. ilex) in southern France. Sampling was undertaken for five years in the UK and for four years in France. All the specimens from the UK, except Acarina, Collembola and Nematocera were identified to species or, occasionally, to morphotype.
2. In terms of overall numbers, species richness and biomass, the results for Q. robur and Q. petraea in the UK were very similar. Their samples contained over three times the biomass and nearly double the number of species compared with those from the introduced oak species (Q. cerris and Q. ilex).
3. The ordinal composition was very similar on Q. robur and Q. petraea, and that on Q. cerris showed closer concordance to the composition of these trees than to that of Q. ilex in the UK. The ordinal composition of the faunas of the two native oak species in France showed closer concordance to each other than to any of the oak species in the UK. The proportion of Psocoptera was much higher in the UK, and that of Thysanoptera was higher in France.
4. The guild composition in terms of numbers, species richness and biomass were closely correlated on Q. robur and Q. petraea, and on Q. robur in two different woods, which argues for an underlying determinism in the development of community structure. The guild composition on the introduced species (Q. cerris and Q. ilex) was most closely correlated when expressed as species richness.
5. The similarity of the guild composition on the oak species in the UK in terms of the actual species found was tested by a modified Sørensen's Index. This showed that the guilds could be ranked in the following order of decreasing similarity: epiphyte fauna, tourists, scavengers, phytophages, parasitoids-predators.
6. There were distinct seasonal patterns. In terms of species richness the values showed a general trend peaking in summer and early autumn, but biomass peaked in May on the native oak species, mainly due to Lepidopterous larvae. The ratio of prey to predator and parasitoid biomass had a distinct seasonal pattern, there being an excess of prey in May, but almost an equivalence throughout the rest of the season. This may reflect the high population of spiders in the late summer and autumn, which are likely to feed on tourists. Most classical ecosystem models do not allow for this latter important source of food that is not itself dependent on the communities' habitat.
7. The epiphyte dwelling guild (principally grazing Psocoptera) was a major component of the fauna in terms of numbers on the evergreen Q. ilex in UK. This has been reported for other studies of evergreen species in temperate climates.

Monoclonal antibody against Rab8 from Bombyx mori (Lepidoptera: Bombycidae)

Tomohide UNO, Takuya NAKADA, Yuichi UNO, Kengo KANAMARU, Hiroshi YAMAGATA, Masahiko NAKAMURA, Michihiro TAKAGI

Eur. J. Entomol. 104 (4): 641-645, 2007 | DOI: 10.14411/eje.2007.080

Small GTPases of the Rab family are key regulators of membrane trafficking. Monoclonal antibodies are useful tools for identifying proteins that interact with other proteins and for examining their tissue distribution. We selected a monoclonal antibody against Rab8 of Bombyx mori L. It specifically recognized amino acid residues 30-109, which are conserved among Rab8 proteins, and did not recognize any other Rab proteins. Western blotting using the antibody revealed one band in the brains of B. mori and rat. Far-Western blotting analysis detected three proteins interacting with Rab8. These results indicate that this antibody is useful for clarifying the physiological function of Rab8 of B. mori and other species. This is a report of a study on a monoclonal antibody against insect Rab protein.

Climate signals are reflected in an 89 year series of British Lepidoptera records

Roger L.H. DENNIS, Tim H. SPARKS

Eur. J. Entomol. 104 (4): 763-767, 2007 | DOI: 10.14411/eje.2007.097

Historical data sources on abundance of organisms are valuable for determining responses of those organisms to climate change and coincidence of changes amongst different organisms. We investigate data on the general abundance of Lepidoptera over an 89 year period 1864-1952. We related abundance to monthly mean temperature and precipitation and the winter North Atlantic Oscillation (NAO) index, and to numbers of migrants from an independent source. Abundances of Lepidoptera were significantly positively correlated with current year temperatures for May to September and November and significantly negatively correlated with temperatures in January. Numbers were also negatively correlated with rainfall for April and May and annual total of the current year and with August in the previous year. Abundance of Lepidoptera decreased significantly with an increasing winter NAO index. Increased overall abundance in Lepidoptera coincided significantly with increased numbers of migrants. The climate associations were very similar to those previously reported for butterfly data collected by the British Butterfly Monitoring Scheme; although warm and drier summers were generally beneficial to Lepidoptera populations, wet summers and winters and mild winters were not. We discuss the implications for Lepidoptera biology and populations in regions of Britain in the face of projected climate changes.

Geographic variation in body and ovipositor sizes in the leaf beetle Plateumaris constricticollis (Coleoptera: Chrysomelidae) and its association with climatic conditions and host plants

Teiji SOTA, Masakazu HAYASHI, Tsuyoshi YAGI

Eur. J. Entomol. 104 (2): 165-172, 2007 | DOI: 10.14411/eje.2007.025


Plateumaris constricticollis
is a donaciine leaf beetle endemic to Japan, which lives in wetlands and uses Cyperaceae and Poaceae as larval hosts. We analyzed geographic variation in body size and ovipositor dimensions in three subspecies (constricticollis, babai, and toyamensis) in different climatic conditions and on different host plants. In addition, the genetic differentiation among subspecies was assessed using nuclear 28S rRNA gene sequences. The body size of subspecies toyamensis is smaller than that of the other subspecies; mean body size tended to increase towards the northeast. Ovipositor length and width are smaller in subspecies toyamensis than in the other subspecies. Although these dimensions depend on body size, ovipositor length still differed significantly between toyamensis and constricticollis-babai after the effect of body size was removed. Multiple regression analyses revealed that body size and ovipositor size are significantly correlated with the depth of snow, but not temperature or rainfall; sizes were larger in places where the snowfall was greatest. Haplotypes of the 28S rRNA gene sequence were not shared among the subspecies. Subspecies constricticollis and babai each had a unique haplotype, whereas subspecies toyamensis had four haplotypes, indicating differentiation among local populations within toyamensis. The evolution of body and ovipositor size in relation to habitat conditions and host plants is discussed.

Ejaculate size varies with remating interval in the grasshopper Chorthippus parallelus erythropus (Caelifera: Acrididae)

Klaus REINHARDT

Eur. J. Entomol. 104 (4): 725-729, 2007 | DOI: 10.14411/eje.2007.092

The number of sperm a male ejaculates is influenced, among other factors, by male age, time since last copulation and possibly a combination of both. Males of Chorthippus parallelus erythropus were subjected to three successive matings in which males had a remating interval of either one or three days. The first ejaculate was very variable. It contained a mean of 433,000 sperm. If there was a one-day interval between matings, the second and third ejaculate comprised 16-19% of the number of sperm in the first ejaculate, respectively. Its sister taxon, the subspecies Chorthippus p. parallelus showed a similar second ejaculate size but the third ejaculate further declined to 8-10% compared to the first. If there were three days between matings, second and third ejaculates comprised 148.3% and 63.1% of the number of sperm in the first ejaculate in Chorthippus p. erythropus. This was markedly different to two individuals of Chorthippus p. parallelus where second and third ejaculates comprised 597% and 416% of the first. It is speculated that this indicates an overall higher sperm production because testis size was also larger in Chorthippus p. parallelus than Chorthippus p. erythropus. The results also show that theoretical models on sperm allocation may underestimate the rate and age-dependency of sperm replenishment.

Preliminary phylogeny of Tribolium beetles (Coleoptera: Tenebrionidae) resolved by combined analysis of mitochondrial genes

Nevenka MEŠTROVIĆ, Brankica MRAVINAC, Miroslav PLOHL, Đurđica UGARKOVIĆ, Branka BRUVO-MAĐARIĆ

Eur. J. Entomol. 103 (3): 709-715, 2006 | DOI: 10.14411/eje.2006.094

The phylogenetic relationships of the three major species groups of Tribolium (Coleoptera: Tenebrionidae) were inferred using the simultaneous analysis of 642 bp of the most conserved part of mitochondrial DNA (mt DNA) cytochrome oxidase I (COI) and 448-452 bp of mt 16S rDNA. High sequence divergence was observed for both genes even among sibling species. The analysis of the combined segments of COI and 16S rDNA sequences produced a phylogenetic tree with moderate level of confidence. The tree topology showed monophyly of the genus Tribolium whose species were separated into three groups: "brevicornis" group (with T. brevicornis as the only representative), "castaneum" group (with T. castaneum, T. freemani, T. madens and T. audax) and "confusum" group (with T. confusum, T. anaphe and T. destructor). Sibling species pairs T. castaneum - T. freemani and T. madens - T. audax are clearly resolved. The preliminary results presented here give moderate support to the previously proposed phylogeny based on morphological data.

The head morphology of Ascioplaga mimeta (Coleoptera: Archostemata) and the phylogeny of Archostemata

Thomas HÖRNSCHEMEYER, Jürgen GOEBBELS, Gerd WEIDEMANN, Cornelius FABER, Axel HAASE

Eur. J. Entomol. 103 (2): 409-423, 2006 | DOI: 10.14411/eje.2006.055

Internal and external features of the head of Ascioplaga mimeta (Coleoptera: Archostemata) were studied with micro X-ray computertomography (µCT) and nuclear magnetic resonance imaging (NMRI). These methods allowed the reconstruction of the entire internal anatomy from the only available fixed specimen. The mouthparts and their associated musculature are highly derived in many aspects. Their general configuration corresponds to that of Priacma serrata (the only other archostematan studied in comparable detail). However, the mandible-maxilla system of A. mimeta is built as a complex sorting apparatus and shows a distinct specialisation for a specific, but still unknown, food source. The phylogenetic analysis resulted in the identification of a new monophylum comprising the genera [Distocupes + (Adinolepis +Ascioplaga)]. The members of this taxon are restricted to the Australian zoogeographic region. The most prominent synapomorphies of these three genera are their derived mouthparts.

Effect of early succession in wildflower areas on bug assemblages (Insecta: Heteroptera)

Thomas FRANK, Irene KÜNZLE

Eur. J. Entomol. 103 (1): 61-70, 2006 | DOI: 10.14411/eje.2006.011

One way of reducing the rapid decline in biological diversity in agricultural landscapes is to establish wildflower areas. The species richness and abundance of heteropteran bugs in twenty 1- to 4-year-old wildflower areas and winter wheat fields were compared, and the effects of succession in the wildflower areas investigated. Vegetation and environmental parameters (plant species richness, vegetation structure, flower abundance, field size, surrounding landscape) and their effects on bug species were explored. Total species richness and abundance of bugs were significantly lower in wheat fields than in wildflower areas but did not differ in the wildflower areas of different ages. The numbers of zoophagous bugs in the wildflower areas were positively correlated with the age of the wildflower areas. Correspondence analysis showed that the bug species composition in the winter wheat fields was very similar but strongly separated from that in the wildflower areas. The species composition of bugs in the wildflower areas became increasingly dissimilar with advancing successional age. In a partial canonical correspondence analysis, the bug assemblage was significantly associated with the number of perennial plant species, the number of annual plant species and vegetation structure, which accounted for 13.4%, 12.6% and 7.2% of the variance, respectively. As wildflower areas clearly increased heteropteran diversity on arable land and bug species composition changed with increasing successional stage, the establishment of a mosaic of wildflower areas of different age is recommended as it enables the survival of heteropteran bugs with different life history traits.

Increased xylem ingestion and decreased phloem ingestion in the aphid Acyrthosiphon pisum (Hemiptera: Aphididae) parasitised by Aphidius ervi (Hymenoptera: Braconidae)

Claudio C. RAMÍREZ, Cristian A. VILLAGRA, Hermann M. NIEMEYER

Eur. J. Entomol. 103 (1): 263-265, 2006 | DOI: 10.14411/eje.2006.032

The effects of parasitisation by Aphidius ervi on the feeding behaviour of the aphid Acyrthosiphon pisum were studied. There was progressive increase in the time devoted to xylem ingestion (G waveform) and concomitant decrease in time devoted to phloem ingestion (E2 waveform) in parasitized relative to unparasitized aphids, as the time from parasitisation increased. These changes are interpreted as a way aphids compensate for metabolic changes occurring during parasitisation.

Crustacean red pigment-concentrating hormone Panbo-RPCH affects lipid mobilization and walking activity in a flightless bug Pyrrhocoris apterus (Heteroptera) similarly to its own AKH-peptides

Radomír SOCHA, Dalibor KODRÍK, Rostislav ZEMEK

Eur. J. Entomol. 104 (4): 685-691, 2007 | DOI: 10.14411/eje.2007.086

In the present study we tested whether the walking activity of macropterous females of the flightless wing-polymorphic bug Pyrrhocoris apterus (L.) can be stimulated by its native adipokinetic hormone Peram-CAH-II and the crustacean red pigment-concentrating hormone (Panbo-RPCH), and the effectiveness of the latter hormone in a lipid mobilization assay. Two different doses (10 or 40 pmol) of Peram-CAH-II or Panbo-RCPH were injected into 10-day-old macropterous females of P. apterus to evaluate their effects on the walking activity of treated females. The results obtained showed a significant stimulation of walking activity only with the lower dose (10 pmol) of either hormone Peram-CAH-II or Panbo-RPCH. On the contrary, the walking activity of the same-aged females of macropterous morph treated with the higher dose (40 pmol) of these hormones was decreased. The energy substrates mobilized in Panbo-RPCH-treated macropterous females were lipids. The question of whether the stimulation of locomotion by Panbo-RPCH is limited only to P. apterus or if it might also represent an important function of this hormone in other insects or even in crustaceans is discussed.

Pristinochterus gen. n. (Hemiptera: Ochteridae) from the Upper Mesozoic of northeastern China

Yunzhi YAO, Wanzhi CAI, Dong REN

Eur. J. Entomol. 104 (4): 827-835, 2007 | DOI: 10.14411/eje.2007.103

A new genus of velvety shore bugs, Pristinochterus gen. n., with one new species, Pristinochterus zhangi sp. n., are described. The specimens were collected from the Late Jurassic to Early Cretaceous Yixian Formation and Early Cretaceous Jiufotang Formation in northeastern China. This finding represents the first record of fossil velvety shore bugs from China. Among the specimens, four well-preserved nymphs are reported for the first time. The placement of the new genus within Ochteridae is briefly discussed. A key to the world genera of Ochteridae is provided.

Mating competition and parentage assessment in Ptomascopus morio (Coleoptera: Silphidae): A case for resource defense polygyny

Seizi SUZUKI, Masahiro NAGANO, Norio KOBAYASHI

Eur. J. Entomol. 103 (4): 751-755, 2006 | DOI: 10.14411/eje.2006.099


Ptomascopus morio
of both sexes are attracted to vertebrate carcasses, a necessary resource for reproduction. The stage during reproduction that resource defense was most intense and the hypothesis that large beetles were better competitors and sired a larger share of the offspring were supported and tested. Male-male aggression (pushing, biting and mounting) was commonly observed before and during oviposition, but rarely after the larvae hatched. Few female-female aggressive interactions were observed at any time. Parentage analysis of the offspring of six groups of two males and two females each reproducing on a separate carcass revealed that the large males sired more of the offspring than small males. Paternity analysis, using AFLP markers, revealed that larger males had higher paternity than smaller males, but the number of eggs produced by each female did not differ between large and small females. This suggests that competition among males is intense until the end of oviposition and that resident (large) males can acquire more mates and sire more offspring than smaller males; competition among females was not evident at any time.

Morphology, bioacoustics and phylogeography of the Isophya major group (Orthoptera: Tettigoniidae: Phaneropterinae): A species complex occurring in Anatolia and Cyprus

Hasan SEVGILI, Battal ÇIPLAK, Klaus Gerhard HELLER, Ali DEMIRSOY

Eur. 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.

Parasitoid complex and parasitism rates of the horse chestnut leafminer, Cameraria ohridella (Lepidoptera: Gracillariidae) in the Czech Republic, Slovakia and Slovenia

Lubomír VOLTER, Marc KENIS

Eur. J. Entomol. 103 (2): 365-370, 2006 | DOI: 10.14411/eje.2006.049

The horse chestnut leaf miner, Cameraria ohridella Deschka & Dimić, is a species of unknown origin that recently invaded most of Europe, causing serious damage to horse chestnut trees, Aesculus hippocastanum. Parasitism was studied over a period of three years in the region of Plzeň in the Czech Republic. Additional collections were made in Slovakia and Slovenia. The parasitoid complex, dominated by polyphagous idiobiont parasitoids of the family Eulophidae, is similar to that found in other studies in Europe. Minotetrastichus frontalis (Nees) was the most abundant parasitoid found, except in Slovakia where Pediobius saulius (Walker) dominated. One parasitoid species, the eulophid Cirrospilus diallus (Walker) was recorded for the first time from C. ohridella. A new method is proposed to calculate stage-specific and total parasitism rates. Parasitism rates of spinning larvae and pupae were higher than of feeding larvae; however, total parasitism was low. We estimated that between 1% and 17% of moths died from parasitism during the larval and pupal stages whereas the rate of mortality caused by other factors varied from 7% to 62%, depending on the locality, year and generation. The proposed method for calculating total parasitism, based on the integration of stage-specific parasitism rates, which takes into account the mortality not directly attributed to parasitism, is discussed and compared with other methods commonly used in studies on C. ohridella.

Abundance of non-target pests in transgenic Bt-maize: A farm scale study

Xavier PONS, Belén LUMBIERRES, Carmen LÓPEZ, Ramon ALBAJES

Eur. J. Entomol. 102 (1): 73-79, 2005 | DOI: 10.14411/eje.2005.010

The impact of transgenic Bt-maize, expressing the Cry1Ab protein, on aphids, leafhoppers, cutworms and wireworms was evaluated at the farm scale by comparing their abundance on Bt-plots and those sown with the isogenic variety over three consecutive growing seasons. The impact of Bt-maize was different on each of the three-herbivore groups. There were significantly more aphids on the Bt-maize but in terms of aphid species, the difference was only statistically significant for Sitobion avenae and not for the other three most abundant species (Metopolophium dirhodum, Rhopalosiphum padi and Macrosiphum euphorbiae). The analysis of aphid age structure showed consistently more individuals on Bt-plots; differences were significant for alates, apterous adults and young nymphs of R. padi, apterous adults and apterous fourth instar nymphs of S. avenae, alates, apterous adults and apterous fourth instar nymphs of M. dirhodum. Leafhoppers (Zyginidia scutellaris), particularly mature nymphs, were also more abundant on the Bt-maize. In spite of this there was no difference in leafhopper damage to Bt and non Bt-maize. The reasons for this are unclear but may be due to changes in Bt-maize that favoured aphids and leafhoppers. Differences in aphid and leafhopper densities were not high enough to affect yield. However, they may have affected the availability of prey for polyphagous predators such as Orius sp. The Bt-maize did not affect the incidence of cutworms (Agrotis segetum) or wireworms (Agriotes lineatus). These results indicate that Bt-maize does not have a negative impact on the non-target maize biocenosis at the farm scale.

Systematic revision and cladistic analysis of the Patagonian genus Platesthes (Coleoptera: Tenebrionidae)

Gustavo E. FLORES

Eur. J. Entomol. 101 (4): 591-608, 2004 | DOI: 10.14411/eje.2004.083

The genus Platesthes Waterhouse, 1845 (Pimeliinae: Praocini), distributed in the Patagonian steppes in southern Argentina and Chile, is revised. A phylogeny of its 13 species is proposed, based on 48 morphological characters. The cladistic analysis provides one most parsimonious cladogram showing that three unambiguous synapomorphic characters of external morphology and male genitalia support the monophyly of Platesthes. This article includes a redescription of the genus, redescriptions of its species, an identification key, habitus photographs of the most representative species, illustrations of external morphology, genital features and metendosternites, a cladogram and distribution maps. A discussion of the biogeography and status of conservation of Platesthes in the Patagonian steppes and in Central Chile is presented. A new Platesthes species is described: P. neuquensis sp. n. and P. hirtipes Kulzer, 1962 stat. n. is elevated to species status. Other valid species of the genus are: P. depressa (Guérin-Ménéville, 1841), P. similis Kulzer, 1956, P. unicosta Kulzer, 1956, P. nigra Kulzer, 1956, P. pilosa Kulzer, 1956, P. vidali Peña, 1986, P. burmeisteri Haag-Rutenberg, 1877, P. granulipennis Kulzer, 1956, P. kuscheli Kulzer, 1958, P. humeralis Kulzer, 1958 and P. silphoides Waterhouse, 1845 (type species), for which a lectotype is designated.

Larval morphology of three species of Hygrobiidae (Coleoptera: Adephaga: Dytiscoidea) with phylogenetic considerations

Yves ALARIE, Rolf G. BEUTEL, Chris H.S. WATTS

Eur. J. Entomol. 101 (2): 293-311, 2004

A provisional larval groundplan of the family Hygrobiidae is provided through descriptions of internal and external features of three of six extant species, Hygrobia hermanni (Fabricius, 1775), H. wattsi Hendrich 2001 and H. australasiae (Clark, 1862) and phylogenetic interpretations. Hygrobiidae larvae are morphologically differing dramatically from all other known Adephaga by 20 autapomorphies. Structures involved with feeding, i.e., mouthparts, prepharynx and foregut are highly modified as a result of a specialisation on small tubificid worms and chironomid larvae. A placement of Hygrobiidae within Dytiscoidea is well supported by the reduced condition of the terminal abdominal segments, and the presence of 10 ancestral setae on femur and a clade comprising Hygrobiidae, Amphizoidae, and Dytiscidae by the presence of thin and elongate caudal tentorial arms, a very strong musculus verticopharyngalis and a longitudinally divided adductor tendon of the mandible. A highly modified foregut, reduced terminal spiracles VIII and the presence of tubular gills are features which distinguish hygrobiid larvae from those of other groups of Dytiscoidea (i.e, Amphizoidae, Noteridae, Dytiscidae). A sister-group relationship between Hygrobiidae and Dytiscidae is indicated by a distinctly shortened and transverse prepharynx and a cerebrum and suboesophaeal ganglion shifted to the anterior third of the head. Larvae of the Australian species H. wattsi and H. australasiae share the presence of a bluntly rounded mandible and an apical position of the primary pore MNd in instar I as potential synapomorphies.

Linkage analysis of the visible mutations Sel and Xan of Bombyx mori (Lepidoptera: Bombycidae) using SSR markers

Xuexia MIAO, Muwang LI, Fangyin DAI, Cheng LU, Marian R. GOLDSMITH, Yongping HUANG

Eur. J. Entomol. 104 (4): 647-652, 2007 | DOI: 10.14411/eje.2007.081

Wild type silkworm larvae have opaque white skin, whereas the mutants Sel (Sepialumazine) and Xan (Xanthous) are yellow-skinned. Previous genetic analysis indicated that Sel and Xan are on established linkage groups 24 (0.0) and 27 (0.0), respectively. However, in constructing a molecular linkage map using simple sequence repeat (SSR) loci, we found that the two mutations were linked. To confirm this finding, we developed a set of SSR markers and used them to score reciprocal backcross populations. Taking advantage of the lack of crossing-over in female silkworms, we found that the progeny of backcrosses between F1 females and males of the parental strains (BC1F) of the two visible mutations had the same inheritance patterns linked to the same SSR markers. This indicated that the two visible mutations belonged to the same chromosome. To confirm this finding, we tested for independent assortment by crossing Sel and Xan marker strains with each other to obtain F1 and F2 populations. Absence of the expected wild type class among 5000 F2 progeny indicated that the two visible mutations were located on the same linkage group. We carried out recombination analysis for each mutation by scoring 190 progeny of backcrosses between F1 males and parental females (BC1M) and constructed a linkage map for each strain. The results indicated that the Sel gene was 12 cM from SSR marker S2404, and the Xan gene was 7.03 cM from SSR marker S2407. To construct a combined SSR map and to avoid having to discriminate the two similar dominant mutations in heterozygotes, we carried out recombination analysis by scoring recessive wild type segregants of F2 populations for each mutation. The results showed that the Sel and Xan genes were 13 cM and 13.7 cM from the S2404 marker, respectively, consistent with the possibility that they are alleles of the same locus, which we provisionally assigned to SSR linkage group 24. We also used the F2 recessive populations to construct two linkage groups for the Sel and Xan genes.

Body weight distributions of central European Coleoptera

Werner ULRICH

Eur. J. Entomol. 104 (4): 769-776, 2007 | DOI: 10.14411/eje.2007.098

Species number - body weight distributions are generally thought to be skewed to the right. While this pattern is well documented in vertebrates, comparative studies on species rich invertebrate taxa are still scarce. Here I show that the weight distributions of central European Coleoptera (based on 8257 species body weight data compiled from Freude et al., 1964-1994) are predominantly right skewed. Skewness and species richness per taxon were positively correlated. The number of modes of the body weight distributions was negatively correlated with species richness. 273 of the 558 genera had bimodal distributions. Species richness per genus did not significantly depend on mean genus body weight. In general the coleopteran size distributions differed from those of European Hymenoptera but were similar to the respective distributions of vertebrates. I conclude that we should be cautious when generalizing patterns found in one taxon.

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