Fulltext search in archive



« advanced mode »

 previous    ...   18   19   20   21   22  23   24   25   26   27   28    next 

Results 631 to 660 of 825:

Flightless Hawaiian Hemerobiidae (Neuroptera): Comparative morphology and biology of a brachypterous species, its macropterous relative and intermediate forms

Catherine A. TAUBER, Maurice J. TAUBER, Jon G. GIFFIN

Eur. J. Entomol. 104 (4): 787-800, 2007 | DOI: 10.14411/eje.2007.100

Five flightless species of Micromus are known from the Hawaiian Archipelago; only one, the rare Micromus usingeri, is reported from the Island of Hawai'i. Herein, we report the natural occurrence of intermediates between this brachypterous species and its near relative, the macropterous Micromus longispinosus. We compare some morphological and life-history characteristics of the two species and the intermediates. Our study shows that: (1) The two closely related species are broadly distributed on Hawai'i, but they appear to be allopatric altitudinally. (2) M. usingeri is associated with a cool, misty, high-altitude environment, M. longispinosus with warmer, rainy conditions at lower elevations. The intermediates occur in both types of situations and generally at intermediate elevations. (3) The macropterous M. longispinosus has large, oblong, flexible, membranous forewings and hind wings. In contrast, the brachypterous M. usingeri has convex, shortened, elytra-like forewings with reticulate venation, and very small, thick, triangular, stub-like hind wings with greatly reduced venation. The wings of intermediate specimens exhibit a broad range of variation between the two species. (4) Several characteristics of wing venation are highly correlated with reduced wing size; others are not. (5) Aside from the wings, adults of M. usingeri and M. longispinosus differ in relatively few morphological features, most notably the antennal and metatibial length, prothoracic length, mesothoracic length and width, and the length of the spine-covered process on the posteroventral margin of the male T9+ectoproct. The intermediate specimens are variable in adult characteristics, but they generally fall between the two species. (6) Egg size and larval characteristics (except the body length of the fully-fed first and third instars) do not differ between the two species. (7) The evolution of the wing variation is discussed.

Revision of Afrocrania (Coleoptera: Chrysomelidae: Galerucinae) Part II: Species in which the males lack head cavities or extended elytral extrusions

Thomas WAGNER

Eur. J. Entomol. 104 (4): 801-814, 2007 | DOI: 10.14411/eje.2007.101

In this second part of the revision of Afrotropical Afrocrania Hincks, 1949 (= Pseudocrania Weise, 1892, not Pseudocrania MCoy, 1851), a group of Galerucinae restricted to Africa, additional material is revised. Herein, species in which the males lack deep head cavities, partly horned antennomeres, or extended elytral extrusions, but usually have small post-scutellar extrusions or depressions, are considered. Material of Afrocrania pauli (Weise, 1903), comb. n. (= Candezea pauli Weise, 1903), and A. famularis (Weise, 1904), comb. n. (= Monolepta famularis Weise, 1904; = Candezea atripennis Laboissière, 1931, syn. n.) is studied. Lectotypes are designated for A. pauli, A. famularis and C. atripennis. Six new species, A. aequatoriana sp. n., A. minima sp. n., A. nigra sp. n., A. occidentalis sp. n., A. pallida sp. n. and A. weisei sp. n. are described. Distribution patterns are mapped. Together with the already revised species there are 16 valid Afrocrania species are hitherto known. Its phylogenetic position within the Galerucinae is discussed, identification keys to males and females for all known taxa are presented.

Molecular differentiation of the four most commonly occurring Trichogramma (Hymenoptera: Trichogrammatidae) species in China

Zheng-Xi LI

Eur. J. Entomol. 104 (3): 363-367, 2007 | DOI: 10.14411/eje.2007.054


Trichogramma dendrolimi
, T. ostriniae, T. confusum and T. evanescens are the four most commonly occurring Trichogramma species with overlapping distribution in China. They are the most frequently used egg parasitoids for biological control of lepidopterous crop pests in China. It is difficult to differentiate Trichogramma species because of their small size and lack of differences in morphological characters. Different molecular markers were employed to molecularly characterize and differentiate these species, including direct amplification of the internally transcribed spacer 2 (ITS2) of ribosomal DNA by polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), random amplified polymorphic DNA (RAPD) and species-specific primers. The results showed that direct amplification of ITS2 could not clearly discriminate these species, but they could be differentiated using RFLP pattern obtained with endonucleases EcoRI and HindIII. The banding pattern produced by RAPD is irreproducible so it is not a suitable way to identify Trichogramma species. Finally, the species-specific primers designed based on ITS2 sequences could unequivocally distinguish the four species. The species-specific primer-based protocol proved to be the most convenient and time saving method for the identification of Trichogramma species by creating a unique PCR product, which can be used in surveying natural populations of Trichogramma species. This is the first report of the prompt identification of the four most commonly occurring Trichogramma species in China.

bmpkci is highly expressed in a resistant strain of silkworm (Lepidoptera: Bombycidae): Implication of its role in resistance to BmDNV-Z

Ke-Ping CHEN, Hui-Qing CHEN, Xu-Dong TANG, Qin YAO, Lin-Ling WANG, Xu HAN

Eur. J. Entomol. 104 (3): 369-376, 2007 | DOI: 10.14411/eje.2007.055

Using the fluorescent differential display technique, a special band named Bm541 was identified by screening for differentially expressed genes in the resistant silkworm strain Qiufeng, the susceptible strain Huaba35, and the near isogenic line BC6, which carries the resistant gene to Bombyx mori densonucleosis virus (BmDNV). After applying the 5'RACE technique with specially designed primers, a 1148 bp cDNA clone containing a 387 bp open reading frame (ORF) was obtained. This gene was registered in GenBank under the accession number AY860950. The deduced amino acid sequence showed a 73.1% identity to the protein kinase C inhibitor (PKCI) of Drosophila pseudoobscura. In the deduced sequence of BmPKCI, the histidine triad (HIT) motif, which is essential for PKCI function, and the α-helix region, which is conserved among the PKCI family, were present. The data from quantitative real-time PCR (QRT-PCR) suggest that the expression levels of bmpkci in BC6 and Qiufeng both with BmDNV-Z are significantly higher than those in Huaba35, which indicate that BmPKCI plays a role in resistance to BmDNV-Z.

Dispersal and reproductive responses of the water strider, Aquarius paludum (Hemiptera: Gerridae), to changing NaCl concentrations

Manabu KISHI, Tetsuo HARADA, Kenji FUJISAKI

Eur. J. Entomol. 104 (3): 377-383, 2007 | DOI: 10.14411/eje.2007.056

The responses of females of the water strider, Aquarius paludum, to changes in NaCl concentration were examined in the laboratory. The insects were sampled seasonally in 2002 and 2003 at two reservoirs in Kochi, Japan, connected by a waterway, one at the mouth of the river with high NaCl concentrations (the range in NaCl concentration during a year: 0.1-1.08%) and one 700 m upstream, where the salinity was lower (0.03-0.23%). Sudden increase in NaCl concentration, from 0.45 to 0.9%, after adult strider emergence suppressed reproduction and promoted flight activity, whereas a decrease in salinity did not affect either trait. In the field, A. paludum was univoltine in brackish and multivoltine in freshwater ponds. Thus, the number of breeding periods per year was limited by fluctuations in the NaCl concentration in brackish habitats. Our results suggest that A. paludum can breed in brackish waters when the NaCl concentration is below the limitation for reproduction and growth. Abrupt increases in NaCl concentration caused by seawater surges, such as those following typhoons, can trigger the migration of individuals, which move to areas of lower NaCl concentration and so mix the genes of individuals inhabiting brackish and freshwater bodies.

Cold tolerance and trehalose accumulation in overwintering larvae of the codling moth, Cydia pomonella (Lepidoptera: Tortricidae)

Abbas KHANI, Saeid MOHARRAMIPOUR, Mohsen BARZEGAR

Eur. J. Entomol. 104 (3): 385-392, 2007 | DOI: 10.14411/eje.2007.057

Seasonal variations in the supercooling point, survival at low temperatures and sugar content were studied in field-collected codling moth larvae. The supercooling point of field-collected larvae decreased significantly from a mean value of -13.4°C in August 2004 (feeding larvae) to -22.0°C in December 2004 (overwintering larvae). Survival at -20°C/24 h was 0% during early autumn, whereas it increased to approximately 60% during winter. The survival at low temperature was well correlated with the supercooling point. The supercooling point of the diapause destined larvae decreased from -16.9 to -19.7°C between September and October as the larvae left the food source and spun a cocoon. For early-diapause larvae, exposure to 5°C/30 days has an additional effect and decreased the supercooling point from -19.7 to -21.3°C. One-month exposure of overwintering larvae to 5°C led to a mortality of 23% in early diapause larvae, while only 4% of diapause larvae died after acclimation. Overwintering larvae accumulated trehalose during winter. There was approximately a threefold increase in trehalose content between larvae at the onset of diapause (5.1 mg/g fresh weight) and larvae in a fully developed diapause (18.4 mg/g fresh weight) collected in January. Trehalose content was correlated with supercooling capacity, survival at low temperatures and chilling tolerance, suggesting that trehalose may play some role in the development of cold tolerance in this species.

Influence of different diets and oviposition substrates on Lygus rugulipennis biology (Heteroptera: Miridae)

Gianandrea SALERNO, Francesca FRATI, Eric CONTI, Ferdinando BIN

Eur. J. Entomol. 104 (3): 417-423, 2007 | DOI: 10.14411/eje.2007.061

The aim of this study was to evaluate the effects of different diets on the development and reproduction of Lygus rugulipennis Poppius (Heteroptera: Miridae). Using 2 laboratory generations (F1 and F2) obtained from field-collected L. rugulipennis, the following diets were tested: beans, beans plus Tenebrio molitor (L.) (Coleoptera: Tenebrionidae) pupae, and a commercial artificial diet, which was developed for mass rearing of Lygus hesperus Knight. As oviposition substrates, beans and agar/parafilm rolls were used. Our data show that both the artificial diet and the artificial oviposition substrate were ineffective substitutes for beans for both laboratory generations. Stage-dependent and total survival rates clearly indicated that F1 Lygus bugs survive significantly longer when they are reared on vegetable substrates i.e., beans and beans plus pupae. The differential effects of the diets were more pronounced in the F2 generation, in which the embryonic development was longer for eggs from females reared on the artificial diet than on beans, and in which the second instar nymphs did not survive on the artificial diet. Both the total duration of post-embryonic development and the longevity of F1 males were shorter on the artificial diet than on beans. Female fecundity was affected by diet in terms of total duration of the oviposition period and mean number of eggs laid/female, since these parameters were lower on the artificial substrate, compared with those obtained on the bean substrate. However, the diet did not affect the morphological parameters, as there were no significant variations in weight, width of cephalic capsule, and tibia and hemelytra length. Since L. rugulipennis cannot be reared on the commercially available artificial diet, we discuss the necessity to improve both the artificial diet and oviposition substrate so that this Lygus bug and its specific egg parasitod Anaphes fuscipennis Haliday (Hymenoptera: Mymaridae) can be mass reared.

The development of sexual differences in body size in Odonata in relation to mating systems

Martin-Alejandro SERRANO-MENESES, Mónica AZPILICUETA-AMORÍN, Tamás SZÉKELY, Alex CÓRDOBA-AGUILAR

Eur. J. Entomol. 104 (3): 453-458, 2007 | DOI: 10.14411/eje.2007.065

Adult body size is the result of important environmental, maternal and/or genetic effects acting on animals during development. Here we investigate how sexual size dimorphism (SSD) develops in seven species of Odonata: Anax imperator, Cordulegaster boltonii, Onychogomphus uncatus, Oxygastra curtisii (Anisoptera), Cercion lindeni, Ischnura graellsii and Platycnemis acutipennis (Zygoptera). SSD of both the last larval and adult stages of the same individuals, which were reared under laboratory conditions, was measured. The aims were to investigate (i) whether SSD develops during the larval stage, (ii) the direction of larval and adult SSD, and (iii) whether the direction of adult SSD can be predicted by the mating system of a given species (e.g. males of territorial species being larger than females and the opposite for non-territorial species). We found that although larval differences in size may be present between the sexes, these are not necessarily shown in the adult stage (they may change or disappear). Also, the mating system was not related to patterns of adult SSD. Differences in SSD in larvae may be caused by differential use of resources via differential niche-utilisation or sex-specific growth patterns. We highlight the fact that sexual selection favouring large male size and fecundity selection, which selects for large females may be acting on the observed patterns in SSD in adults.

Sexual dimorphism and light/dark adaptation in the compound eyes of male and female Acentria ephemerella (Lepidoptera: Pyraloidea: Crambidae)

Ting Fan (Stanley) LAU, Elisabeth Maria GROSS, Victor Benno MEYER-ROCHOW

Eur. J. Entomol. 104 (3): 459-470, 2007 | DOI: 10.14411/eje.2007.066

In the highly sexual-dimorphic nocturnal moth, Acentria ephemerella Denis & Schiffermüller 1775, the aquatic and wingless female possesses a refracting superposition eye, whose gross structural organization agrees with that of the fully-winged male. The possession of an extensive corneal nipple array, a wide clear-zone in combination with a voluminous rhabdom and a reflecting tracheal sheath are proof that the eyes of both sexes are adapted to function in a dimly lit environment. However, the ommatidium of the male eye has statistically significantly longer dioptric structures (i.e., crystalline cones) and light-perceiving elements (i.e., rhabdoms), as well as a much wider clear-zone than the female. Photomechanical changes upon light/dark adaptation in both male and female eyes result in screening pigment translocations that reduce or dilate ommatidial apertures, but because of the larger number of smaller facets of the male eye in combination with the structural differences of dioptric apparatus and retina (see above) the male eye would enjoy superior absolute visual sensitivity under dim conditions and a greater resolving power and ability to detect movement during the day. The arrangement of the microvilli in the rhabdom of both genders suggests that their eyes are polarization-sensitive, an ability they would share with many aquatic insects that have to recognize water surfaces. Although sexual recognition in A. ephemerella is thought to chiefly rely on pheromones, vision must still be important for both sexes, even if the females are wingless and never leave their watery habitat. Females swim actively under water and like their male counterparts, which fly above the surface of the water, they would have to see and avoid obstacles as well as potential predators. This, together with a small incidence of winged females, we believe, could be the reason why the eyes of female A. ephemerella are less regressed than those of other sexually dimorphic moths, like for instance Orgyia antiqua. Another, but difficult to test, possibility is that male and female A. ephemerella have diverged in their behaviour and habitat preferences less long ago than other sexually dimorphic moths.

An Erratum has been published for this article: https://doi.org/10.14411/eje.2008.065

The microspatial distribution of beetles (Coleoptera) on exposed riverine sediments (ERS)

Adam J. BATES, Jon P. SADLER, Joe N. PERRY, Adrian P. FOWLES

Eur. J. Entomol. 104 (3): 479-487, 2007 | DOI: 10.14411/eje.2007.068

Exposed Riverine Sediments (ERS) are often characterised by a high diversity of microhabitats due to strong lateral gradients in temperature, humidity, inundation frequency and availability of aquatic food resources and to variations in the degree of vegetation cover, sediment size and sorting. This variation, potentially in combination with interspecific competitive interactions, is thought to drive the microspatial distribution of ERS invertebrates. This research investigated the microspatial distribution of six ERS specialist beetles across three discreet patches of ERS. In particular it examined the temporal stability of species distributions, and their spatial association with environmental variability and other species. The research used a grid of 204 modified dry pitfall traps over six sampling periods in which weather conditions and water levels were stable, and used the Spatial Analysis by Distance IndicEs (SADIE) method to test the significance of spatial distributions and associations. Strong and significant microspatial zonation was observed for all species, and with few exceptions these distributions were remarkably stable across the study period. This zonation was mainly associated with elevation and proximity to the water, and several species were consistently spatially associated or disassociated with one another. This suggests that laterally more extensive patches of ERS support more species. Operations that reduce the size of ERS patches, such as channelisation, aggregate extraction and regulation are therefore likely to reduce ERS invertebrate diversity.

Variation in dung beetle (Coleoptera: Scarabaeoidea) assemblages with altitude in the Bulgarian Rhodopes Mountains: A comparison

Jorge M. LOBO, Evgeni CHEHLAROV, Borislav GUÉORGUIEV

Eur. J. Entomol. 104 (3): 489-495, 2007 | DOI: 10.14411/eje.2007.069

Variation with altitude in the composition of dung beetle assemblages and species richness was measured by sampling in spring, summer and autumn, both manually and with pitfall traps at twelve localities in the western Rhodopes Mountains. Non-parametric estimates indicate that most of the regional species pool was collected, some 73% of all taxa previously recorded in the entire region. The rate of species richness decrease with altitude is around 11 species per km, with an evident altitudinal change in the incidence of two main dung beetle functional groups in which Aphodiinae species begin to dominate Rhodopes assemblages at around 1400-1500 m. Species richness of dung pats is dominated by Scarabaeinae in spite of the fact that the number of Aphodiinae species is highest at each locality. Thus, Aphodiinae species are the main contributors to both local and regional pool richness and to species turnover between localities. These characteristics are similar to those observed in the assemblages from another European mountain range, also located near the Mediterranean-Eurosiberian boundary, the Iberian Central System. These results suggest that eastern European dung beetle assemblages are similar in compositional turnover and species richness variation with altitude to that observed in western Europe and North America.

Redescription of a weevil Paramecops sinaitus (Coleoptera: Curculionidae: Molytinae) from the Sinai and an ecological study of its interaction with the Sinai milkweed Asclepias sinaica (Gentianales: Asclepiadaceae)

Tim NEWBOLD, Massimo MEREGALLI, Enzo COLONNELLI, Maxwell BARCLAY, Shereen ELBANNA, Nancy ABU FANDUD, Frank FLEGG, Rasha FOUAD, Francis GILBERT, Vanessa HALL, Claire HANCOCK, Mona ISMAIL, Samr OSAMY, Isra'a SABER, Fayez SEMIDA, Samy ZALAT

Eur. J. Entomol. 104 (3): 505-515, 2007 | DOI: 10.14411/eje.2007.071

We collected specimens of Paramecops sinaitus (Pic, 1930) (Curculionidae: Molytinae) from south Sinai in Egypt, which enabled us to make the first complete description of this species. We also include some taxonomic remarks on the genus. Paramecops solenostemmatis (Peyerimhoff, 1930) is a synonym of Paramecops sinaitus. We propose the new combination Paramecops sogdianus (Nasreddinov, 1978), based on Perihylobius sogdianus Nasreddinov, 1978, which would make Perihylobius and Paramecops synonymous. Like other Paramecops species, P. sinaitus appears to share a close interaction with Asclepiads, in this case the Sinai milkweed Asclepias sinaica (Boiss.) Muschl., 1912 (Asclepiadaceae). We investigated the oviposition behaviour of female weevils to test whether it is linked to larval performance, as predicted by coevolutionary theory. We found that female oviposition preference was positively related to plant size and to the volume of the seed follicles in which the eggs were laid. The survival of eggs was negatively related to plant size, perhaps due to plant differences in the production of defensive cardenolides. Larval survival was not related to plant size but increased with follicle volume, probably as a result of competition for food. Paramecops is relatively sedentary and nocturnal in its behaviour. Night-time observations of behaviour showed that weevils were more active at lower temperatures.

Phylogeny of European Dolichopus and Gymnopternus (Diptera: Dolichopodidae) and the significance of morphological characters inferred from molecular data

Marco Valerio BERNASCONI, Marc POLLET, Manuela VARINI-OOIJEN, Paul IRVINE WARD

Eur. J. Entomol. 104 (3): 601-617, 2007 | DOI: 10.14411/eje.2007.075

Dolichopodidae (over 6000 described species in more than 200 genera) is one of the most speciose families of Diptera. Males of many dolichopodid species, including Dolichopus, feature conspicuous ornaments (Male Secondary Sexual Characters) that are used during courtship. Next to these MSSCs, every identification key to Dolichopus primarily uses colour characters (postocular bristles; femora) of unknown phylogenetic relevance. The phylogeny of Dolichopodidae has rarely been investigated, especially at the species level, and molecular data were hardly ever involved. We inferred phylogenetic relationships among 45 species (57 samples) of the subfamily Dolichopodinae on the basis of 32 morphological and 1415 nucleotide characters (810 for COI, 605 for Cyt-b). The monophyly of Dolichopus and Gymnopternus as well as the separate systematic position of Ethiromyia chalybea were supported in all analyses, confirming recent findings by other authors based purely on morphology. Within Dolichopus, stable species groups could be assigned to four distinct categories on the basis of their statistical support in 7 phylogenetic analyses: (i) clades significantly supported in all analyses, (ii) clades supported in trees based on DNA and combined data, but only partly in morphological trees, (iii) clades significantly supported in trees based on DNA and combined data, but not in morphological trees, and (iv) clades consistently supported only in morphological trees. The phylogeny generated here provides a better understanding of the phylogenetic relevance of some debated morphological characters used for species and species-group characterizations in the most commonly used identification keys. In this respect, postocular bristle colour proved of little phylogenetic relevance since every group with species featuring black bristles also included species with partly yellow bristles. Entirely or partly infuscated femora explained the nodes of three stable species groups and even revealed an incorrect polarity of this morphological character in three species. Four of 6 complex MSSCs and 5 of 8 more common MSSCs were found consistently in further species groups.

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.

Pre-adult development and longevity in natural populations of Lymantria dispar (Lepidoptera: Lymantriidae)

Jelica LAZAREVIÆ, Vesna PERIÆ-MATARUGA, Nikola TUCIÆ

Eur. J. Entomol. 104 (2): 211-216, 2007 | DOI: 10.14411/eje.2007.033

While most theoretical models for the evolution of ageing assume that duration of pre-adult development does not affect the longevity, experimental data are still controversial and inconsistent. Here we examined the short-term and long-term pattern of pre-adult development time and longevity in populations of the gypsy moth (Lymantria dispar) originating from either oak forest (Quercus petrea), a suitable, or locust-tree forest (Robinia psedoacacia), a poor habitat. Using a full-sib design, we examined the genetic correlations between traits found in larvae reared on oak or locust-tree leaves. We detected only negative and insignificant genetic correlations, except for males from the Robinia population reared on oak leaves where the correlation was negative and significant. Our results also showed that a population living 40 generations in the locust-tree forest exhibited a significantly higher longevity than the Quercus population, whereas a significant difference between these two populations in pre-adult development time does not exist. The results are discussed in relation to the potential effect of stress selection in moulding the longevity of the gypsy moth.

Eurytoma robusta (Hymenoptera: Eurytomidae), a local key factor in the population dynamics of Urophora cardui (Diptera: Tephritidae): a comparative analysis

Helmut ZWÖLFER, Marc BÖHEIM, Erwin BECK

Eur. J. Entomol. 104 (2): 217-224, 2007 | DOI: 10.14411/eje.2007.034


Eurytoma robusta
Mayr (Chalcidoidea) exploits host galls either as a primary or secondary parasitoid, an entomophytophagous inquiline or occasionally even as a predator. We present data on its ecology and impact on gall densities and population trends of the gall fly Urophora cardui (L.) on Cirsium arvense (L.) Scop. Habitat preference, host gall selection, clutch size, and high incidence of superparasitism causing empty gall cells show that E. robusta, a generalist with a broad host spectrum, is relatively poorly adapted to parasitising U. cardui. The influence of E. robusta on U. cardui in the Belfort-Sundgau region (1970-2004), in the Upper Rhine Valley (1973-2004) and in north-eastern Bavaria (1977-2004), differed considerably. In the forests of the Upper Rhine Valley and the Belfort-Sundgau region, where U. cardui has relatively stable source-sink populations, E. robusta is present but not the dominant mortality factor of the gall fly. In most areas of north-eastern Bavaria U. cardui occurs in fragmented populations and short lived non-equilibrium metapopulations. In these systems E. robusta became more abundant over the last five years, which resulted in a high incidence of superparasitism, an increase in the number of empty gall cells and reduced gall quality. The greatly increased degree of parasitism and an excess of empty cells resulted recently in the collapse of most local populations of U. cardui in the study area south of Bayreuth (north-eastern Bavaria). Together with earlier records the data presented here suggest that in north-eastern Bavaria E. robusta cause fluctuations in the abundance of U. cardui, which have a periodicity of 5-7 years. A remarkable feature of the oligophagous E. robusta is its high fidelity to formerly abundant U. cardui populations, which, with declining host densities, leads to overexploitation, resulting in a high incidence of superparasitism and high larval mortality. The possible influence of the habitat structure on the effect of E. robusta on the population dynamics of U. cardui is discussed. Our data plus that of other authors suggest that, with regard to U. cardui, E. robusta can develop a temporary local host specialisation.

The role of fungal taxa and developmental stage of mushrooms in determining the composition of the mycophagous insect community in a Japanese forest

Satoshi YAMASHITA, Naoki HIJII

Eur. J. Entomol. 104 (2): 225-233, 2007 | DOI: 10.14411/eje.2007.035

We hypothesize that differences in fungal taxonomic groups may exert a direct influence on the composition of mycophagous insect communities, and that the relative importance of taxonomy compared to other fungal traits may change as the mushrooms decay. We conducted a 3-year field survey and analyzed the species composition of mycophagous insect communities using partial canonical correspondence analysis (partial CCA). We collected 2457 mushrooms belonging to 27 genera, and 4616 insects belonging to 16 families emerged from 439 of the mushrooms. For the whole insect community, fungal genera explained 10-19% of the total variance in the family composition of the insect communities of mushrooms at different developmental stages. Only the fungal genus Collybia significantly affected the community composition almost irrespective of developmental stage. In the drosophilid community, which consisted of 844 individuals from 9 species, fungal genera explained 19-34% of the total variance. Some fungal genera, such as Amanita and Collybia, affected the drosophilid community, but not at all developmental stages. The number of fungal genera that significantly affected the insect community composition did not differ among fungal stages both in the whole insect community and in the drosophilid community. Thus, our former hypothesis was supported by the present analysis, whereas the latter was not. However, the percentages of variance explained by fungal genera were rather small. This suggests that the importance of fungal genera is likely to be less significant than that of other selection pressures in determining the species composition of mycophagous insect communities.

New significant fossil insects from the Upper Carboniferous of Ningxia in northern China (Palaeodictyoptera, Archaeorthoptera)

Jakub PROKOP, Dong REN

Eur. J. Entomol. 104 (2): 267-275, 2007 | DOI: 10.14411/eje.2007.041

New palaeodictyopterid Namuroningxia elegans sp. n. (Namuroningxiidae fam. n.) and archaeorthopterid Sinopteron huangheense gen. n., sp. n. (uncertain family assignment) are described from the Tupo Formation (Upper Carboniferous, Namurian, northern China, Ningxia Hui Autonomous Region). Both new taxa exhibit a unique structure of their wing venation pattern. The Namuroningxiidae fam. n. bears a mosaic of characters diagnostic of several "palaeopteran" families throughout Palaeodictyopteroida and Eupalaeoptera. This fact is highly interesting in reference to the Namurian age known for the occurrence of the first winged insects as well as the palaeogeographical position of the locality far from all sites in Laurussia. The preliminary study of entomofauna diversity exhibit frequent occurrence of archaeorthopterid wing fragments (e.g., Sinopteron huangheense) forming up to 40 percent of all insect specimens demonstrate high abundance of this group in the early Late Carboniferous ecosystems.

Revision of the Oriental leafhopper genus Toba with description of a related new genus (Hemiptera: Cicadellidae: Stegelytrinae)

Cong WEI, Mick D. WEBB, Yalin ZHANG

Eur. J. Entomol. 104 (2): 285-293, 2007 | DOI: 10.14411/eje.2007.044

The Oriental leafhopper genus Toba Schmidt is reviewed and placed in the subfamily Stegelytrinae Baker. Its type species, T. fasciculata Schmidt, and a new species T. sandakanensis Wei & Webb, are described with details of the male and female genitalia given for the first time. A related new genus and species, Paratoba longa Wei & Webb, gen. n. and sp. n., are described. The subfamily status and the morphological similarities between these two genera and other taxa are discussed.

Cleorodes Warren, 1894 does not belong in the tribe Boarmiini (Lepidoptera: Geometridae)

Jaan VIIDALEPP, Toomas TAMMARU, Niina SNÄLL, Kai RUOHOMÄKI, Niklas WAHLBERG

Eur. J. Entomol. 104 (2): 303-309, 2007 | DOI: 10.14411/eje.2007.046

The geometrid genus Cleorodes is shown to belong in the tribe Gnophini (sensu lato) and not in Boarmiini as previously assumed. The conclusion is based on an analysis of morphological characters of a number of genera in these tribes. Moreover, the result is unambiguously supported by a phylogenetic analysis of DNA sequence variation in three nuclear gene regions (segments D1 and D2 of 28S rRNA, and elongation factor 1α) and a mitochondrial gene, cytochrome oxidase-1. The phylogenetic hypothesis is based on a combined sequence data set, which was analysed using direct optimisation.

Period of adult activity and response to wood moisture content as major segregating factors in the coexistence of two conifer longhorn beetles, Callidiellum rufipenne and Semanotus bifasciatus (Coleoptera: Cerambycidae)

Ryûtarô IWATA, Takahisa MARO, Yasushi YONEZAWA, Tôru YAHAGI, Yoshirô FUJIKAWA

Eur. J. Entomol. 104 (2): 341-345, 2007 | DOI: 10.14411/eje.2007.049

The cerambycid borers Callidiellum rufipenne (Motschulsky) and Semanotus bifasciatus (Motschulsky) infest coniferous logs in Japan, with the latter distributed in the north and at high altitudes, where both species occur sympatrically. Semanotus bifasciatus adults were active at low temperatures and very active after sunset, and less active but never inactive in the daytime, whereas C. rufipenne adults were usually active at high temperatures and almost only in the daytime. At an almost constant temperature, C. rufipenne adults were almost inactive at night, whereas S. bifasciatus adults showed only an obscure decline in activity in the morning. Of a horizontal log, the upper surface tended to be drier and lower surface wetter, and C. rufipenne larvae grew large if they were in the upper part of a log, whereas S. bifasciatus larvae grew large if in the lower part. Thus, the coexistence of these two species can be ascribed to two major segregation factors: adult segregation based on temperature and sunshine, and larval segregation associated with the moisture content of the wood.

Cicadas "dig wells" that are used by ants, wasps and beetles

Kazuo YAMAZAKI

Eur. J. Entomol. 104 (2): 347-349, 2007 | DOI: 10.14411/eje.2007.050

There is a high density of the cicada Cryptotympana facialis (Walker) (Hemiptera: Cicadidae) in urban parks in central Japan during summer. This cicada uses its stylet to pierce holes in the trunks of keyaki trees, Zelkova serrata and then feeds on the exuding xylem sap. Three ant species, Formica japonica Motschulsky, Lasius japonicus Santschi and Crematogaster matsumurai Forel (Hymenoptera: Formicidae) were observed aggregatively feeding on these exudates. In addition, two wasp species, Polistes jokohamae Radoszkowski (Hymenoptera: Vespidae), and Ampulex dissector (Thunberg) (Hymenoptera: Sphecidae) fed on the sap. These ants and wasps can therefore be classified as commensals. Two flower chafers, Protaetia brevitarsis (Lewis) and P. orientalis submarumorea (Burmeister) (Coleoptera: Scarabaeidae) were also observed displacing cicadas from their feeding sites and feeding on the exuding sap. Thus, these chafers can be classified as both commensals and kleptoparasites.

A serine protease from the midgut of the bumblebee, Bombus ignitus (Hymenoptera: Apidae): cDNA cloning, gene structure, expression and enzyme activity

Young Moo CHOO, Kwang Sik LEE, Hyung Joo YOON, Sang Beom LEE, Ji Hyeon KIM, Hung Dae SOHN, Byung Rae JIN

Eur. J. Entomol. 104 (1): 1-7, 2007 | DOI: 10.14411/eje.2007.001

A serine protease gene was cloned from the bumblebee, Bombus ignitus. The B. ignitus serine protease (BiSP) gene spans 1702 bp and consists of four introns and five exons coding for 250 amino acid residues. Southern blot analysis of genomic DNA suggested that BiSP gene is a single copy gene. The cDNA encoding BiSP was expressed as a 28-kDa polypeptide in baculovirus-infected insect cells and the recombinant BiSP showed activity in a protease enzyme assay. BiSP was specifically expressed in the midgut of B. ignitus queens, males, and workers, suggesting that the BiSP is a gut enzyme involved in the digestion of dietary proteins.

Moist habitats are essential for adults of the Antarctic midge, Belgica antarctica (Diptera: Chironomidae), to avoid dehydration

Joshua B. BENOIT, Giancarlo LOPEZ-MARTINEZ, Michael A. ELNITSKY, Richard E. LEE, David L. DENLINGER

Eur. J. Entomol. 104 (1): 9-14, 2007 | DOI: 10.14411/eje.2007.002

Desiccation resistance of adult males and females of the midge, Belgica antarctica (Diptera: Chironomidae) was evaluated to determine how this short-lived stage maintains water balance in the dry Antarctic environment. Both sexes had slightly lower water content (≈60%) and a higher dehydration tolerance (>30% water loss) than most other insects. Water loss rates were high and increased rapidly at temperatures above 15°C, indicating that the adult midges are more hygric than many other polar terrestrial arthropods. Water gain was accomplished by free water uptake with minimal or no contribution from absorption of water vapor or metabolic water production. Parameters related to water balance did not differ among populations from different islands. Overall, the high water requirements of the adult midge appear to be a significant challenge and presumably dictate that the adult midges must emerge during the brief period when free water is readily available and seek protected microhabitats that facilitate water retention.

Feeding conditions modify the photoperiodically induced dispersal of the water strider, Aquarius paludum (Heteroptera: Gerridae)

Tetsuo HARADA, Tatsuya NISHIMOTO

Eur. J. Entomol. 104 (1): 33-37, 2007 | DOI: 10.14411/eje.2007.005

Overwintering adults of the water strider, Aquarius paludum were collected from the field in fall and kept under short days (12L : 12D) at 20°C for a week. A control group was then kept at 12L : 12D and fed daily, and three experimental groups were transferred to 15.5L : 8.5D and fed at different frequencies: daily or every 2nd or 3rd day. Temperature was kept at 20°C. Flight behaviour of the adults in the four groups was recorded every 10 days up to the end of the 5th week when the adults were dissected. State of the flight muscles and reproductive organs (ovaries and testes) was recorded. Flight ability of the adults fed every 3rd day (Group 3) was higher than that of those fed daily (Group 1). Seventy percent of the females that were fed every 3rd day (Group 3) remained in diapause for 5 weeks, in spite of the reproduction promoting long-days, while none of the females fed every day remained in diapause (Group 1). Flight muscle histolysis, promoted by long-days, was inhibited by poor feeding conditions. Thus, they can migrate and seek more suitable water bodies rich in food. The modifying effect of the availability of food on the trade-off between reproduction and flight is recorded here for the first time for a carnivorous insect.

Aggregation characteristics of three species of Coccinellidae (Coleoptera) at hibernation sites

Alois HONÌK, Zdeòka MARTINKOVÁ, Stano PEKÁR

Eur. J. Entomol. 104 (1): 51-56, 2007 | DOI: 10.14411/eje.2007.008

Adults of some coccinellid species overwinter in aggregations consisting of many individuals. They may clump because adults are attracted to particular environmental stimuli and/or of an innate tendency to join conspecific individuals. Aggregation behaviour was studied in Coccinella septempunctata L., which forms small clumps, and Ceratomegilla undecimnotata (Schneider) and Hippodamia variegata (Goeze), which form large clumps. Adults were recorded at five hilltop hibernacula (400-1500 m altitude) in central Europe (50-51°N, 14-16°E) for periods up to 27 years. The hibernacula occur in areas sparsely covered with isolated grass tussocks or completely with stones. Numbers of adults recorded under each of 300-900 stones or among the stems of the grass tussocks were counted every year at each hibernaculum. The degree of aggregation was determined using Taylor's power law. The coccinellid distributions became more aggregated and the size of the aggregations increased as their abundance increased, less in C. septempunctata than in the other two species. Aggregations formed even in the absence of prominent structures, which may attract immigrants, and even when unoccupied stones or tussocks suitable for overwintering were available. Aggregations may be established and their size limited by the strength of the intrinsic preference to join conspecifics. The supposed advantage of aggregated overwintering must be greater than the risk associated with the easy spread of diseases.

Development of the entomopathogenic hyphomycete Lecanicillium muscarium (Hyphomycetes: Moniliales) on various hosts

Hassan ASKARY, Hamid YARMAND

Eur. J. Entomol. 104 (1): 67-72, 2007 | DOI: 10.14411/eje.2007.011

The present scanning electron microscopy study describes the development of Lecanicillium muscarium, strain DAOM 198499, on the surface of diverse hosts, including Sphaerotheca fuliginea, a fungal host, and Macrosiphum euphorbiae and Aphidius nigripes, insect hosts. The hosts were sprayed with a conidial suspension of L. muscarium (107 conidia/ml). The specimens used in the SEM investigation were collected at particular periods after spraying and prepared for scanning using standard methods. Germination tubes developed twenty-four hours after applying L. muscarium conidia to each host. Hyphae were attached to the host by a thin mucilaginous matrix. Seventy-two hours after spraying, hyphae of S. fuliginea had collapsed and were encircled by the parasite, and primary sporulation of L. muscarium was observed. On the aphid host, colonization started with adherence of the conidia to the host cuticle, followed by conidial germination and growth of mycelium on the surface of the insect's integument. After 48 to 72 h, post colonization, the first sporulation was observed on the cuticle, particularly at articulations. The mode of parasitism of A. nigripes by this fungus was similar to that of the aphid. Development of L. muscarium was observed on both mummified aphids (containing the pupae of parasitoids) and adult parasitoids.

Population, ecology and morphology of Saga pedo (Orthoptera: Tettigoniidae) at the northern limit of its distribution

Anton KRI©TÍN, Peter KAÒUCH

Eur. J. Entomol. 104 (1): 73-79, 2007 | DOI: 10.14411/eje.2007.012

The bush-cricket Saga pedo, one of the largest predatory insects, has a scattered distribution across 20 countries in Europe. At the northern boundary of its distribution, this species is most commonly found in Slovakia and Hungary. In Slovakia in 2003-2006, 36 known and potentially favourable localities were visited and at seven this species was recorded for the first time. This species has been found in Slovakia in xerothermic forest steppes and limestone grikes (98% of localities) and on slopes (10-45°) with south-westerly or westerly aspects (90%) at altitudes of 220-585 m a.s.l. (mean 433 m, n = 20 localities). Most individuals (66%) were found in grass-herb layers 10-30 cm high and almost 87% within 10 m of a forest edge (oak, beech and hornbeam being prevalent). The maximum density was 12 nymphs (3rd-5th instar) / 1000 m2 (July 4, 510 m a.s.l.). In a comparison of five present and previous S. pedo localities, 43 species of Orthoptera were found in the present and 37 in previous localities. The mean numbers and relative abundance of species in present S. pedo localities were also significantly higher. S. pedo individuals at the northern boundary of their distribution were expected to be smaller and lighter because of suboptimal ecological conditions there. However, the body size of S. pedo individuals from these areas were similar to the average value for the whole area. Based on analyses of present and former localities and the Orthopteran assemblages around S. pedo, the factors endangering this species, and methods for conserving it and its habitat are discussed.

Female copulatory tubes and the subdivision of the genus Anthocoris (Heteroptera: Anthocoridae: Anthocorini)

Yunling KE, Wenjun BU

Eur. J. Entomol. 104 (1): 89-98, 2007 | DOI: 10.14411/eje.2007.014

We report a systematic study of the female copulatory tubes of forty species in the genus Anthocoris, most of which are from the Northern Hemisphere. Our results indicate that female copulatory tubes can be used as a reliable character to identify females and analyze phylogenetic relationships in this genus. We propose thirteen species groups based on the copulatory tubes of females, other morphological characters of both sexes, and the previous species groups adopted in the continental faunas.

Afroaltica subaptera, new genus and new species of flea beetles from the southern Africa (Coleoptera: Chrysomelidae: Alticinae)

Maurizio BIONDI, Paola D'ALESSANDRO

Eur. J. Entomol. 104 (1): 99-103, 2007 | DOI: 10.14411/eje.2007.015


Afroaltica subaptera
, a new genus and species of flea beetles (Chrysomelidae: Alticinae) from the eastern regions of southern Africa (Eastern Transvaal and Kwazulu-Natal), is described. Afroaltica gen. n. shows some similarities with the genus Dibolia Latreille, 1829 but it is easily distinguishable mainly by the simple-shaped apical spur of hind tibiae, not bifid. External habitus, scanning electronic micrographs of particular morphological features and line drawings of metafemoral spring and male and female genitalia of the new taxon are provided.

 previous    ...   18   19   20   21   22  23   24   25   26   27   28    next