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Results 1051 to 1080 of 1606:

Why does the Namib Desert tenebrionid Onymacris unguicularis (Coleoptera: Tenebrionidae) fog-bask?

Strinivasan G. NAIDU

Eur. J. Entomol. 105 (5): 829-838, 2008 | DOI: 10.14411/eje.2008.110

Dehydration of Onymacris unguicularis (Haag) for 10 days at 27°C resulted in a weight loss of 14.9%, and a 37% decrease in haemolymph volume. Although there was an overall decrease in the lipid content during this period, metabolic water production was insufficient to maintain total body water (TBW). Rehydration resulted in increases in body weight (6.2% of initial weight), TBW (to normality), and haemolymph volume (sub-normal at the end of rehydration). Despite an increase of 44.0 mg in the wet weight of O. unguicularis after drinking for 1h, there was little change in the water content at this time, although the total lipid content increased significantly. Increases in haemolymph osmolality, sodium, potassium, chloride, amino acid and total sugar concentrations during dehydration were subject to osmoregulatory control. No evidence of an active amino acid-soluble protein interchange was noted during dehydration or rehydration. Haemolymph trehalose levels were significantly increased at the end of rehydration (relative to immediate pre-rehydration values), indicating de novo sugar synthesis at this time. Osmotic and ionic regulation was evident during rehydration, but control of OP during haemolymph-dilution is poor and accomplished largely by the addition to the haemolymph of free amino acids and solute(s) not measured in this study. There was little mobilization of sodium and chloride ions from storage sites at this time. The lesser osmoregulatory ability of Onymacris unguicularis and perhaps earlier susceptibility to osmotic stress, a significantly high normal blood glycerol level (relative to other diurnal adesmiine tenebrionids), and a water storage mechanism associated with synthesis of fat, probably all contribute to the development of fog-basking behaviour in this species. Water gain in O. unguicularis during periods of relative drought is probably largely accomplished by a greater food consumption.

A chromosomal study on a Lebanese spittlebug Philaenus arslani (Hemiptera: Auchenorrhyncha: Aphrophoridae)

Anna MARYAÑSKA-NADACHOWSKA, Valentina G. KUZNETSOVA, Hani ABDUL-NOUR

Eur. J. Entomol. 105 (2): 205-210, 2008 | DOI: 10.14411/eje.2008.029

The meadow spittlebug genus Philaenus (Auchenorrhyncha: Aphrophoridae) is known to display marked colour polymorphism. This study presents the results of a karyotype analysis of P. arslani from Lebanon using conventional chromosome staining, C-banding, fluorescent banding using base-specific fluorochromes (CMA3 and DAPI) and AgNOR-staining. This species has 2n = 18 + neo-XY, and differs from P. spumarius both in the number of chromosomes and sex chromosome system. During meiosis, the neo-XY bivalent is clearly heteromorphic being the largest in the complement. Furthermore, sex chromosomes show marked differences in C-banding pattern. The NOR-bearing chromosomes are the first and one of the middle-sized pairs of autosomes. NORs are G-C rich. Furthermore, some blocks of constitutive heterochromatin on the sex chromosomes are also G-C rich. All other C-bands are DAPI or DAPI/ CMA3 positive, thus containing A-T rich DNA. The significant difference in the karyotype of P. arslani and P. spumarius indicates chromosomal transformations during the evolution of the genus Philaenus.

The lock-and-key mechanisms of the internal genitalia of the Noctuidae (Lepidoptera): How are they selected for?

Kauri MIKKOLA

Eur. J. Entomol. 105 (1): 13-25, 2008 | DOI: 10.14411/eje.2008.002

In the Noctuidae, the owlet moths, the internal genitalia, i.e. the aedeagus and vesica (penis) in the males, and the bursa copulatrix in the females, together form a lock-and-key mechanism (LKM). The species-specific structures have their counterparts in the opposite sex. The internal LKM constitutes a specific reproductive isolation mechanism (lock-and-key hypothesis), which seem to be the rule in the ditrysian Lepidoptera, and also occurs in the Carabidae (Coleoptera) and some other insects. In contrast, the external genitalia rarely have species-specific counterparts in the sexes. Several results indicate the presence of LKMs: In the Noctuidae, (1) heterospecific differences in the male vesica may prevent sperm transfer or lead to mechanical failure during copulation, (2) the more complicated the specific genitalia structures, the more aberrations may occur even in conspecific copulations, and (3) in many species pairs and groups, and in one large genus, Apamea, the structures in the opposite sexes show a strictly specific correspondence, but, (4) when there is precopulatory isolation due to differences in pheromone production or perception, the internal genitalia may be identical. Conversely, in the Colias butterflies (Pieridae), (5) frequent heterospecific hybridization is associated with the similarity of the internal genitalia. The LKMs seem to protect genomes against alien genes, supposedly selected for because of the lower fitness of specimens with an imprecise LKM and/or inferiority of hybrids. In the literature, the diversity of the noctuid genitalia has been ascribed to sexual selection, because the females were classified as polyandrous. Most species produce the main part of their eggs monandrously, and remate, if at all, in their old age, and are thus successively monandrous and polyandrous. The allopatric divergence in the structure of the internal genitalia of 39 Holarctic pairs of sister species of Noctuidae is suggested to be due to genetic drift. The insecure function of the female pheromones and external genitalia of males are illustrated with the aid of original photographs.

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.

Winter climates and coldhardiness in terrestrial insects

William J. TURNOCK, Paul G. FIELDS

Eur. J. Entomol. 102 (4): 561-576, 2005

Overwintering insects must avoid injury and death from the freezing of tissues and from metabolic disruptions associated with exposure to low, non-freezing temperatures. The winter climates of the world are classified in relation to insect overwintering on the basis of their minimum temperatures and the duration of the winter (when temperatures are below the thermal range for activity and development). Outside the Tropical Wet zone, the severity of exposure to cold (temperature, snowfall, duration of exposure, predictability, variability) can vary from a few days at 0°C to months below -20°C with extremes as low as -60°C. The severity of the temperature exposure may be ameliorated by the selection by insects of overwintering sites (exposed, partly-exposed, protected). The relationships among overwintering habitats, the minimum winter temperature in climatic zones, and the supercooling points (SCP) of over 350 terrestrial insects from published reports were examined. Variability in the SCP among insects within each climatic zone and habitat was wide. Among the freeze-susceptible species that overwintered in exposed or partly-protected habitats the SCP and the cold severity of climate were correlated. This was not the case for insects that overwintered in protected habitats. The SCP's of freeze-tolerant insects were generally higher than the freeze-susceptible insects, and the SCP's were not tightly linked with the cold severity of climatic zone. Insects, both freeze-susceptible and freeze-tolerant, overwintering in exposed habitats had lower SCP's than insects from habitats that offered some protection from ambient temperatures. Thirty-eight species had reports of SCP's for different geographical locations. Although there were occasionally differences in the SCP's, there was no consistent pattern of insects having lower SCP's when overwintering in colder habitats. The incidence of freeze-tolerance was higher in boreal and polar climatic zones than in climatic zones with warmer winters. Holometabola insects had a higher incidence of freeze-tolerance than hemimetabola insects. Suggestions for future research directions are outlined.

Contrasting levels of polymorphism in cross-amplified microsatellites in two endangered xerothermophilous, obligatorily myrmecophilous, butterflies of the genus Phengaris (Maculinea) (Lepidoptera: Lycaenidae)

Robert RUTKOWSKI, Marcin SIELEZNIEW, Agnieszka SZOSTAK

Eur. J. Entomol. 106 (4): 457-469, 2009 | DOI: 10.14411/eje.2009.058

We analysed the polymorphism of cross-amplified microsatellite loci in two endangered butterflies of the genus Phengaris, which inhabit warm grasslands. Specimens of P. arion and P. 'rebeli' collected in Poland showed contrasting levels of variability in the investigated loci. All six tested microsatellites were highly variable in P. arion, whereas in P. 'rebeli' one locus was monomorphic and the other four loci showed a rather low level of polymorphism. Genetic differentiation was small or moderate among P. arion populations and high among P. 'rebeli' populations. We hypothesise that these differences reflect: (1) the relatively high genetic variability of P. arion compared with other members of the genus, indicated by previous studies on allozymes; (2) the small, in the majority of cases, genetic differentiation among populations of P. arion, which suggests recent gene flow; (3) a decrease in the genetic variability and increased isolation of peripheral populations of P. 'rebeli'. In both species, the occurrence of "null" alleles was suggested for some loci, which should be taken into consideration in future studies of the population structure. Additional analysis performed on the corrected frequency of alleles indicated that "null" alleles constitute only a minor problem when estimating genetic differentiation, using FST and AMOVA, however they strongly influence estimates of heterozygosity and FIS, and inferences about the number of genetic groups and assignment of individuals, especially in the case of 'P. rebeli'.

A review of the European species of Phradis (Hymenoptera: Ichneumonidae: Tersilochinae), with a description of a new species from Spain

Andrey I. KHALAIM, Santiago BORDERA, Alexander RODRÍGUEZ-BERRÍO

Eur. J. Entomol. 106 (1): 107-118, 2009 | DOI: 10.14411/eje.2009.015

European species of the genus Phradis Förster, 1869 are reviewed. A new species from Spain, Phradis mediterraneus sp. n., is described and illustrated. A key to all 24 European species and data on distribution and biology of these species are provided.

Leucopis annulipes larvae (Diptera: Chamaemyiidae) use a furtive predation strategy within aphid colonies

Bruno FRÉCHETTE, François LAROUCHE, Éric LUCAS

Eur. J. Entomol. 105 (3): 399-403, 2008 | DOI: 10.14411/eje.2008.050

A laboratory experiment was conducted to determine whether the predation strategy of larvae of the aphidophagous silver fly Leucopis annulipes Zetterstedt (Diptera: Chamaemyiidae) is furtive, as are larvae of the aphidophagous midge Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae), or active like aphidophagous ladybird beetle larvae (Coleoptera: Coccinellidae). The impact of L. annulipes larvae on pea aphid, Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), colony disturbance was evaluated and compared with that of the furtive predator A. aphidimyza and the active-searching ladybird beetle Harmonia axyridis Pallas. Results indicate that aphids showed significantly fewer defensive acts (dropping, walking away, wriggling) in the presence of L. annulipes larvae than of ladybird beetle larvae. Furthermore, the impact of L. annulipes larvae on aphid colony disturbance was similar to that of A. aphidimyza and to a control treatment without predators. These results clearly indicate that L. annulipes larvae use a furtive predation strategy.

Conservation biological control of spirea aphid, Aphis spiraecola (Hemiptera: Aphididae) on apple by providing natural alternative food resources

Mark W. BROWN, Clarissa R. MATHEWS

Eur. J. Entomol. 105 (3): 537-540, 2008 | DOI: 10.14411/eje.2008.071

Enhancing biological control in orchards is an efficient way to control insect pests. This study investigates the possibility of increasing biological control of spirea aphid by providing alternate food resources, in the form of peach extrafloral nectar, to adult Harmonia axyridis, its primary predator. Two pairs of apple orchards, each having one interplanted with 50% trees bearing extrafloral nectar and one a monoculture, were studied for aphid and predator populations from 1999 to 2005. There were no differences in spirea aphid or predator populations between interplanted and monoculture orchards. However, H. axyridis adults arrived earlier in the interplanted than in the monoculture orchards. In another apple orchard, the effect of peach extrafloral nectar on sentinel spirea aphid colonies surrounding a cluster of potted peach trees, or a cluster of apple trees as a control, was tested in 2007. Only the closest spirea colonies to the potted peach trees, trees within 3 m, showed an increase in biological control. Although there was some indication of enhancement of predation by adult H. axyridis on spirea aphids, adding alternative food resources in the form of peach trees bearing extrafloral nectar resulted in no detectable increase in biological control.

Revision of the genera Anisarthrocera, Rhampholyssa and Rhampholyssodes, description of the new genus Somalarthrocera and a phylogenetic study of the tribe Cerocomini (Coleoptera: Meloidae)

Federica TURCO, Marco A. BOLOGNA

Eur. J. Entomol. 105 (2): 329-342, 2008 | DOI: 10.14411/eje.2008.040

Four genera of the blister beetle tribe Cerocomini are revised, including the new genus Somalarthrocera. The genera Rhampholyssa Kraatz, 1863 and Somalarthrocera comprise two species each, whereas Anisarthrocera Semenow, 1895 and Rhampholyssodes Kaszab, 1983 are monotypic. S. savanicola sp. n. from Kenya is described, S. semirufa (Fairmaire, 1882) comb. n. is proposed, as well as new synonymy: A. batesi (Marseul, 1872) = A. batesi villiersi Kaszab, 1968. Phylogenetic relationships among the six genera of the tribe are defined by a cladistic analysis, which indicates three clades, one basal, represented by the genus Cerocoma Geoffroy, 1762, the second including Anisarthrocera and the pair Rhampholyssa and Rhampholyssodes, and the third including Diaphorocera Heyden, 1863 and Somalarthrocera. Bionomical information available for the four revised genera is summarised. Keys to these genera and to the species of the two non-monotypic genera are presented, as well as diagnoses of genera and species and catalogue of localities. Anisarthrocera is distributed in the northern Persian Gulf, Rhampholyssa in the Turanian depression, Rhampholyssodes is endemic to the eastern Arabian Peninsula, and Somalarthrocera is distributed in Somalia and Kenya. A brief biogeographical analysis of this primarily Palaearctic tribe is also presented.

Habitat use and movement patterns in the endangered ground beetle species, Carabus olympiae (Coleoptera: Carabidae)

Matteo NEGRO, Achille CASALE, Luca MIGLIORE, Claudia PALESTRINI, Antonio ROLANDO

Eur. J. Entomol. 105 (1): 105-112, 2008 | DOI: 10.14411/eje.2008.015

One of the most compelling challenges for conservation biologists is the preservation of species with restricted ranges. Carabus olympiae Sella, 1855, a ground beetle species inhabiting two small areas in the western Italian Alps, is an example of a steno-endemic and endangered insect species. Despite the fact that this species is historically well known to professional and amateur entomologists, its autecology is virtually unknown. In the present study we used pitfall traps to study habitat selection and phenology, and radiotelemetry to measure differences in movement parameters between sexes, habitats and periods. Data from pitfall trapping suggested that C. olympiae actively selects both shrubberies (alpen rose Rhododendron ferrugineum and bilberry Vaccinium myrtillus) and beech forests and avoids pastures, and that population size peaks in July. All radio-tagged individuals (n = 21) moved without a preferred direction, and were more active at night than by day. Males covered greater distances and had more tortuous trajectories than females. Distances covered in forests and alpen rose shrubberies were not significantly different, but paths in beech forests were more convoluted than in shrubberies. The movement pattern observed fits the requirements of a typical "olfactory-tactile" insect predator that looks for prey by systematically exploring its territory. Movement parameters suggested that both beech forests and alpen rose shrubberies are suitable for this species and indicated that the spatial distribution of shrubs in shrubberies can constrain trajectories. The implications for conservation are: (i) any human intervention which results in enlargement of the present coverage of pastures should be controlled; (ii) forest management may be tolerated, with the condition that alpen rose shrubberies remain or develop after tree-cutting; (iii) once a shrubbery has established, it should be preserved through appropriate management.

Effect of photoperiod on parasitization by Trichogramma principium (Hymenoptera: Trichogrammatidae)

Sergey Ya. REZNIK, Nina P. VAGHINA

Eur. J. Entomol. 104 (4): 705-713, 2007 | DOI: 10.14411/eje.2007.089

The effect of photoperiod on parasitization of the eggs of the Angoumois grain moth, Sitotroga cerealella (Olivier, 1789) by Trichogramma principium Sugonyaev & Sorokina, 1976 was investigated under several photoperiodic regimes of L : D = 3 : 21, 6 : 18, 9 : 15, 12 : 12, 15 : 9, 18 : 6 and 21 : 3. In all regimes, certain wasps delayed ovipositing in this non-preferred host. Potential fecundity of T. principium females (the number of mature ovarial eggs at emergence) and subsequent oogenesis (estimated by the number of mature ovarial eggs in non-ovipositing females) was independent of photoperiod. However, the percentage of females that oviposited was higher for females that developed and were kept under 6-12 h long photophase than for those that developed and were kept under ultra short (3L : 21D) and under long (18L : 6D and 21L : 3D) photophases. The average duration of the pre-oviposition (egg retention) period showed the opposite pattern to the photoperiodic response. A possible explanation of this reaction is that the delay in oviposition is adaptive if the probability of finding a better host is high. In autumn, when the last Trichogramma females are still active but their lepidopteran hosts are already much less abundant, then parasitization of any suitable host is the best strategy.

Sociality improves larval growth in the stag beetle Figulus binodulus (Coleoptera: Lucanidae)

Hideaki MORI, Satoshi CHIBA

Eur. J. Entomol. 106 (3): 379-383, 2009 | DOI: 10.14411/eje.2009.048

The benefits for offspring of attendant adult were investigated in the stag beetle Figulus binodulus. The initial growth rate of third-instar larva was significantly higher when the larvae were in a nest with adults compared to those in a nest without adults. The difference in growth rate is reflected in adult body size. Although the presence of adult beetle generally benefited the offspring, the adults did eat some of the larvae. Filial cannibalism was the primary cause of juvenile death in nests with adults. Mortality was lower in nests with adults related to the juveniles compared to nests with unrelated adults, suggesting that infanticide of nest mates may be inhibited. These results suggest that F. binodulus has a level of sociality and nest mate recognition that is very rare in stag beetles. Social behaviour may be more advantageous for small stag beetles than fighting.

Long-distance wind-borne dispersal of the moth Cornifrons ulceratalis (Lepidoptera: Crambidae: Evergestinae) into the northern Mediterranean

Jordi DANTART, Constantí STEFANESCU, Anna ÀVILA, Marta ALARCÓN

Eur. J. Entomol. 106 (2): 225-229, 2009 | DOI: 10.14411/eje.2009.030

On October 2006, during an episode of abnormally warm weather, the African moth Cornifrons ulceratalis (Lederer, 1858) was captured simultaneously for the first time in several sites in north-eastern Spain, the Balearic Islands and southern France. A deep depression situated over the Atlantic at the time gave rise to warm south-westerly winds, accompanied by suspended dust, that blew towards the north-western Mediterranean Basin. Back trajectories of air masses at two different altitudinal levels indicate that the moths most probably originated from an area located in Morocco and northern Algeria, where C. ulceratalis can be extremely abundant. With winter approaching, this invasion of a typically non-migratory species into the north-western Mediterranean Basin provides a good example of the so-called "pied piper" phenomenon, by which wind-borne insects may be carried into areas unfavourable for survival or reproduction. However, because climate change may make the establishment of this and other African species more likely in the future, we suggest that monitoring of this process may become an essential issue in the coming years.

Cereal aphids (Hemiptera: Aphidoidea) in Serbia: Seasonal dynamics and natural enemies

®eljko TOMANOVIÆ, Nickolas G. KAVALLIERATOS, Petr STARÝ, Olivera PETROVIÆ-OBRADOVIÆ, Christos G. ATHANASSIOU, Ljubi¹a ®. STANISAVLJEVIÆ

Eur. J. Entomol. 105 (3): 495-501, 2008 | DOI: 10.14411/eje.2008.064

During 1989-2006 the number of live aphid, mummies, aphid specialist predators and their parasitoids in cereal fields in Serbia were recorded. S. avenae and M. dirhodum were the most common, both on wheat and rye crops. Maximum numbers of cereal aphids were detected between the end of May and the middle of June. A low percentage of mummified aphids was recorded during May and June, but increased rapidly at the beginning of July, when aphids left the wheat crop. Here, we record over 60 species of cereal aphid natural enemies, including primary and secondary parasitoids, aphid specific predators and a wide spectrum of their parasitoids in Serbian cereal crop systems. Aphidius uzbekistanicus Luzhetzki, Aphidius rhopalosiphi De Stefani, Aphidius ervi Haliday and Praon gallicum Starý were the most abundant species of primary parasitoids. Of the secondary parasitoids, six species were dominant with Asaphes suspensus (Nees) and Dendrocerus carpenteri (Curtis) generally the most often recorded. Coccinella septempunctata L. was the most abundant coccinellid and syrphid flies were represented by 11 species, two of which, Sphaerophoria scripta (L.) and Episyrphus balteatus (DeGeer), were the most common.

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.

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.

Life history and reproductive behavior of the endemic Hawaiian Anomalochrysa hepatica (Neuroptera: Chrysopidae): A comparative approach

Maurice J. TAUBER, Catherine A. TAUBER, Timothy W. HILTON

Eur. J. Entomol. 103 (2): 327-336, 2006 | DOI: 10.14411/eje.2006.043

Our study focuses on a series of biological characteristics that Anomalochrysa hepatica exhibits; herein, we compare these features with those expressed by two other species within the endemic Hawaiian lacewing genus. Some of the characteristics (No. 2-3, below) vary greatly among the three congeners and may be of phylogenetic importance; others (No. 1, below) probably are not. Our study showed the following: (1) Developmental response to temperature. Anomalochrysa hepatica's developmental rates under a range of temperatures parallel those of the congener A. maclachlani, but A. hepatica's thermal threshold is lower. It is possible that both species' developmental responses to temperature are subject to considerable geographic variation and thus are of little phylogenetic significance at the species level. (2) Larval color change. Third instars of A. hepatica undergo a striking color change as they mature. In expressing this trait, A. hepatica resembles its closely related congener, A. maclachlani, but differs from the more distantly related congener, A. frater. This color change may have phylogenetic importance. (3) Reproductive behavior. Courtship and mating in Anomalochrysa comprise a consistent sequence of behavioral elements, some of which differ among the three species. For example, during courtship, A. hepatica produces readily audible clicks that are associated with forward flicking of the forewings; in A. maclachlani, readily audible clicking occurs with simultaneous flicking of the fore- and hind wings; in A. frater wing-flicking is present but we did not perceive audible clicks. Some of the interspecific variation in mating behavior may also involve specific morphological modifications; aspects of both the behavioral and morphological variation may provide useful characters for phylogenetic study. (4) Oviposition and rates of egg survival in the field. Unlike other Chrysopidae, endemic Hawaiian Anomalochrysa, including A. hepatica, typically lay unstalked eggs; however, species vary in their patterns of egg laying. Both A. hepatica and A. maclachlani deposit clustered eggs, whereas A. frater lays eggs singly. In nature, the average rate of hatching per A. hepatica egg mass was ~75%. Several species of introduced predators and a species of trichogrammatid parasitoid attacked these eggs.

The identity of Pseudopsila, description of a new subgenus of Psila, and redefinition of Psila sensu lato (Diptera: Psilidae)

Matthias BUCK, Stephen A. MARSHALL

Eur. J. Entomol. 103 (1): 183-192, 2006 | DOI: 10.14411/eje.2006.021

The type species of Pseudopsila Johnson, P. fallax (Loew), and two related species are found to belong in Psila s. str., and Pseudopsila is thus synonymized with Psila Meigen. The remaining species formerly included in Pseudopsila form a monophyletic group here described as Xenopsila Buck subgen. n. [i.e., Psila (Xenopsila) collaris Loew comb. n., P. (X.) bivittata Loew comb. n., P. (X.) lateralis Loew comb. n., P. (X.) arbustorum Shatalkin comb. n., P. (X.) nemoralis Shatalkin comb. n., P. (X.) tetrachaeta (Shatalkin) comb. n., P. (X.) maculipennis (Frey) comb. n., P. (X.) nigricollis (Frey) comb. n., P. (X.) nigrohumera (Wang & Yang) comb. n.]. A key to the Nearctic species of Xenopsila and the Psila fallax-group is provided. The placement of Xenopsila in Psila s. l. is confirmed by newly recognised synapomorphies of the egg stage. The somewhat questionable monophyly of Psila s. l. is confirmed based on these new synapomorphies, thereby slightly expanding its taxonomic limits to also include Asiopsila Shatalkin. The morphology of the male genitalia of Xenopsila is discussed in detail, clarifying confused homologies and character polarities in the hypandrial complex. Evolutionary trends in the development of the hypandrium in the subfamily Psilinae are discussed.

Apoptosis of neuronal cells in the brains of postembryonic silkworms Bombyx mori (Lepidoptera: Bombycidae)

Mi Young KIM, Kang Kim MIN, Chang Ok CHOI, Hwa Young SONG, Chang Lee SEOK, Bong Woo KIM, Pil Don KANG, Soung Hoo JEON, Byung Pil CHO, Yeon Jae BAE, Young-Gyo KO, Bong Lee HEE

Eur. J. Entomol. 106 (3): 335-345, 2009 | DOI: 10.14411/eje.2009.041

The pattern and signal transduction of neuronal apoptosis in the brain of the silk moth, Bombyx mori, during postembryonic life, were characterized. Peak numbers of apoptotic neurons were detected in 4 day old 4th instar larvae, 9 day old 5th instar larvae and 4 day old pupae, indicating three waves of neuronal apoptosis during postembryonic development. Most of the apoptotic neurons were in the lateral portions of the brain. No apoptotic neurons were detected in 1 day old 1st instar larvae or in 7 day old pupae to 1 day old adults. Injection of 20-hydroxyecdysone (20E) into larvae resulted in a substantial increase in the brain in both neuronal apoptosis and cleavage of procaspases-8 and -3 into caspases-8 and -3. However, the injection of larvae with actinomycin D or cycloheximide inhibited death of pre-apoptotic neurons. Both the cleavage of procaspases-8 and -3 and death of pre-apoptotic neurons were inhibited by a general caspase inhibitor and caspase-8 and -3 inhibitors injected into larvae. These results suggest that 20E triggered the synthesis of a new protein that, in turn, induces cleavage of procaspases-8 and -3 into caspases-8 and -3. These caspases are prerequisites for neuronal apoptosis in postembryonic brains.

Food consumption and immature growth of Adalia bipunctata (Coleoptera: Coccinellidae) on a natural prey and a factitious food

Mohammad A. JALALI, Luc TIRRY, Patrick DE CLERCQ

Eur. J. Entomol. 106 (2): 193-198, 2009 | DOI: 10.14411/eje.2009.024

One factor limiting the adoption of aphidophagous coccinellids in augmentative biological control is cost-effective mass production. The use of factitious foods may lower production costs by reducing space and manpower requirements for mass rearing of the predator and its prey and by enhancing mechanization of rearing procedures. The objective of this study was to compare the efficiency of food conversion, consumption indices and growth rates of first to fourth instars of Adalia bipunctata when fed either a mixture of Ephestia kuehniella eggs and fresh bee pollen, or on the natural prey Myzus persicae. Larval survival did not differ among treatments, averaging 80 and 90% on the respective diets. Mean dry body weights of the coccinellid were significantly lower on M. persicae than on the factitious food only for second instars and the pre-pupal stage. Dry food consumption by the predator throughout larval development averaged 20.61 mg on factitious food and 14.82 mg (corresponding to an average of 284 third and fourth instars) on M. persicae. The efficiency of conversion of ingested food for total larval development averaged 25 and 30% on factitious food and aphids, respectively. The relative growth rate of the larval instars was higher on aphids, whereas the consumption index was higher on the mixture of E. kuehniella eggs and pollen. An additional experiment showed that rearing the previous instars on the factitious food had no substantial effect on aphid consumption in the fourth instar. The study suggests that this factitious diet may be an appropriate food source for mass rearing A. bipunctata.

Changes in the volatile profile of Brassica oleracea due to feeding and oviposition by Murgantia histrionica (Heteroptera: Pentatomidae)

Eric CONTI, Claudia ZADRA, Gianandrea SALERNO, Benedetta LEOMBRUNI, Daniela VOLPE, Francesca FRATI, Cesare MARUCCHINI, Ferdinando BIN

Eur. J. Entomol. 105 (5): 839-847, 2008 | DOI: 10.14411/eje.2008.111

The mixture of volatile compounds emitted by Brassica oleracea var. sabauda changed significantly in response to feeding and/or oviposition by Murgantia histrionica (Heteroptera: Pentatomidae). Volatiles were collected from (1) healthy plants and those with (2) feeding punctures, (3) a combination of feeding punctures and oviposition, (4) feeding punctures and one hatched egg mass and (5) plants bearing only an egg mass. In the case of plants with feeding punctures or feeding punctures plus an egg mass, the volatiles were also collected at different time intervals after plants were subjected to these two treatments (0-24 h, 24-48 h and 48-72 h). Gas chromatographic and gas chromatograph-mass spectrometric analysis showed that the percent emission of several compounds changed significantly from plants subjected to the feeding and oviposition or just oviposition. Percentage of terpenes generally decreased after feeding and oviposition, although the percentage emission of (E)-β-caryophyllene from these plants and those with just feeding punctures significantly increased. Plants with just an egg mass emitted linalool de novo but not (E)-β-ocimene. The emission of jasmonates, mainly methyl jasmonate, increased from plants with feeding punctures plus an egg mass compared to those with only an egg mass. Higher percentages of the volatile glucosinolate derivatives (VGSs), mainly 4-methoxy-3-indolylacetonitrile, were emitted by plants with feeding punctures and an egg mass. The percentage emission of most of these compounds increased during the first 24 h after the treatment and then decreased over the next 24 h, except for methyl jasmonate, which remained high also 48-72 h later. The possible ecological roles of such volatiles in plant interactions with the second and third trophic levels are discussed.

The wing stalk in Diptera, with some notes on the higher-level phylogeny of the order

Jaroslav STARÝ

Eur. J. Entomol. 105 (1): 27-33, 2008 | DOI: 10.14411/eje.2008.003

The wing stalk in Diptera is examined, and its structures are re-evaluated and re-interpreted. The non-homology of A2 in Tipulomorpha and "A2" in other Diptera is claimed. Some notes are presented on the higher-level phylogeny of Diptera, especially those concerning Tipulomorpha. The family Trichoceridae is restored among Tipulomorpha, and the Tipulomorpha are re-affirmed as the sister group of the remaining Diptera. The clade Anisopodidae + Culicomorpha + Bibionomorpha is suggested as the sister group of Brachycera.

Male territorial behaviour of the endemic large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis (Hymenoptera: Apidae), on the oceanic Ogasawara Islands

Shinji SUGIURA

Eur. J. Entomol. 105 (1): 153-157, 2008 | DOI: 10.14411/eje.2008.021

The endemic large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis Matsumura (Hymenoptera: Apidae), on the oceanic Ogasawara (Bonin) Islands, located in the northwestern Pacific Ocean, approximately 1000 km south of the Japanese mainland, is a generalist flower visitor. Although the flower-visiting behaviour of X. ogasawarensis females has been frequently recorded, the behaviour of the males in this species has rarely been studied. I observed the territorial behaviour of males on flowers of the native plant species Scaevola sericea Vahl (Campanulales: Goodeniaceae) in a coastal area of Hahajima in early July 2007. Each male chose a particular inflorescence, hovered near it (mean distance, 239 mm from the inflorescence) and patrolled around it for several minutes (mean time, 331 s). Therefore, X. ogasawarensis males exhibit resource-based (i.e., flowers) territoriality. Males frequently attacked other males when defending their territories. However, males did not defend their territories against flower visitors of other species (i.e., introduced honeybees). Therefore, male territorial behaviour in X. ogasawarensis may be related to intrasexual competition for sites visited by females. This is the first report describing the male territorial behaviour of X. ogasawarensis.

Molecular phylogeny of the genus Lythria and description of the male genitalia of L. venustata (Lepidoptera: Geometridae: Sterrhinae)

Erki ÕUNAP, Vladimir MIRONOV, Jaan VIIDALEPP

Eur. J. Entomol. 106 (4): 643-650, 2009 | DOI: 10.14411/eje.2009.080

We present a molecular phylogeny incorporating all five species of the Palaearctic geometrid genus Lythria, based on a 2810-bp combined data matrix comprising the full sequence of the mitochondrial gene cytochrome oxidase subunit one (COI) and fragments of the nuclear genes elongation factor 1 alpha (EF-1α) and wingless (wgl). L. venustata, which was recently rediscovered from Kazakhstan, is shown to be sister taxon to all other members of the genus. The remaining species within the genus form two pairs of sister species: L. purpuraria groups together with L. plumularia, and L. cruentaria with L. sanguinaria. The phylogeny is well supported by characters of the male genitalia of all Lythria species. In addition to the molecular phylogeny of the genus Lythria, we illustrate the external appearance of L. venustata for the first time and describe the anatomy of its male genitalia.

Morphology, taxonomy and distribution of Diphyonyx gen. n., a lineage of geophilid centipedes with unusually shaped claws (Chilopoda: Geophilidae)

Lucio BONATO, Marzio ZAPPAROLI, Alessandro MINELLI

Eur. J. Entomol. 105 (2): 343-354, 2008 | DOI: 10.14411/eje.2008.041

A new genus Diphyonyx is proposed here for a previously unrecognised lineage of geophilid centipedes. It is distinct from other geophilids in its unique combination of morphological characters, including the peculiar shape of the pretarsus of the legs on the anterior part of the trunk. The type species D. conjungens (Verhoeff, 1898), comb. n., is redescribed in detail and its geographical distribution updated (Balkan Peninsula, Anatolia, Crimea). Included in Diphyonyx are also D. sukacevi (Folkmanová, 1956), comb. n., and D. garutti (Folkmanová & Dobroruka, 1960), comb. n., both from southern Russia. D. garutti is raised here to species rank.

The role of plant phenology in the host specificity of Gephyraulus raphanistri (Diptera: Cecidomyiidae) associated with Raphanus spp. (Brassicaceae)

Janine VITOU, Marcela SKUHRAVÁ, Václav SKUHRAVÝ, John K. SCOTT, Andy W. SHEPPARD

Eur. J. Entomol. 105 (1): 113-119, 2008 | DOI: 10.14411/eje.2008.016

Recent host records for Gephyraulus raphanistri (Kieffer), a flower-gall midge, show restriction to Raphanus raphanistrum throughout Europe. Gephyraulus raphanistri has never been reported infesting commercially grown Brassica crops. Historical records showing a broad host range appear to have resulted from confusion with new or as yet undescribed Gephyraulus spp. and Contarinia nasturtii (Kieffer), a known gall-former of Brassica and other related genera. This study tested host specificity of G. raphanistri in the field in Europe by manipulating host plant phenology of actual and potential hosts in the genera Raphanus and Brassica as part of a risk assessment of the insect as a potential biological control agent of R. raphanistrum, one of the most important weeds of crops in Australia. Raphanus raphanistrum raphanistrum (wild radish), R. raphanistrum landra (coastal wild radish), Raphanus sativus (radish) and Brassica napus (oilseed rape cultivar) were phenologically synchronised for initial flowering and planted out in a flowering time and species block design near a natural population of R. r. landra hosting a natural population of G. raphanistri. Three generation peaks in gall formation were observed in the experiment, with galls developing on all test plants with an apparent preference for R. r. landra. The high field specificity of this gall midge is driven by the synchrony of oviposition and flower availability, not host physiological incompatibility or behavioural unacceptability. Commercially grown Brassica spp. are not suitable hosts for G. raphanistri because in the field they differ in flowering phenology from Raphanus raphanistrum. The overlap in the flowering phenology of the crop and weed in Australia makes this insect unsuitable as a biological control agent.

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.

Diversity of ground beetles (Coleoptera: Carabidae) and spiders (Araneae) in roadside verges with grey hair-grass vegetation

Jinze NOORDIJK, André P. SCHAFFERS, Karlè V. SÝKORA

Eur. J. Entomol. 105 (2): 257-265, 2008 | DOI: 10.14411/eje.2008.036

Roadside verges in densely populated areas are often a significant addition to the total semi-natural area and as such may contribute to the conservation of biodiversity. Furthermore, they can enhance the ecological cohesion of a region, especially when the existing nature reserves are small and/or highly fragmented. We investigated the occurrence of ground beetles and spiders in six highway verges with grey hair-grass vegetation in the Veluwe region, The Netherlands. Total species number in the verges was similar to the values found in nearby nature reserves with comparable vegetation, but the ground beetles tended to be more abundant in the reserves. Many stenotopic species were present in the verges, confirming the significant conservation value of this habitat. However, compared with the nature reserves, there were fewer species of stenotopic ground beetles and the stenotopic spiders were less abundant in the verges. From our knowledge of the biology and ecology of the species captured it seems likely that this is attributable to differences in "habitat quality". In the verges, species preferring bare sand are scarcer, and the weighted mean body length of ground beetles is shorter than in nature reserves. This suggests that the sward in the road verges is too dense and the suitable vegetation too patchy to sustain some of the stenotopic species. Habitat analyses support this contention: Compared with the nature reserves, the verges had proportionally less bare sand, more herb and tree cover and the vegetation patches were smaller. The strategy suggested to promote stenotopic species entails removing encroaching trees and shrubs from the verges in order to expand the nutrient-poor zone and (re-)create pioneer conditions. Subsequent management should aim at further improving the road verges as extensions of nutrient-poor habitat.

The pollens consumed by common green lacewings Chrysoperla spp. (Neuroptera: Chrysopidae) in cabbage crop environment in western France

Johanna VILLENAVE, Dominique THIERRY, Abdullah AL MAMUN, Thierry LODÉ, Elizabeth RAT-MORRIS

Eur. J. Entomol. 102 (3): 547-552, 2005 | DOI: 10.14411/eje.2005.078

The pollens consumed by common green lacewings Chrysoperla spp. in crop environment in western France, were analysed. The diverticulum contents including quantity of pollen of Chrysoperla adults were analysed to compare a feeding behaviour between the sexes. Females consume more pollen than males. The feeding behaviour of the two main species present was compared, yielding new insights into differences between species within the complex Chrysoperla carnea (Stephens).

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