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Genetic diversity of the xerothermic weevils Polydrusus inustus and Centricnemus leucogrammus (Coleoptera: Curculionidae) in central EuropeLukasz KAJTOCH, Dorota LACHOWSKA-CIERLIK, Mieczyslaw MAZUREur. J. Entomol. 106 (3): 325-334, 2009 | DOI: 10.14411/eje.2009.040 Phylogeography, genetic diversity, and demography of central European populations of two flightless xerothermic weevils, Polydrusus inustus and Centricnemus leucogrammus, were studied based on the polymorphism of three mtDNA genes (COII, CytB, and ND1). Results indicate that these xerothermic beetles may have different origins. P. inustus is a recent migrant as the parthenogenetic form has a low level of genetic diversity and lacks a geographic population structure. This is probably a result of a recent (before the end of last glaciation) expansion and/or present dispersal mediated by humans. On the other hand, C. leucogrammus appears to be a relic species as the populations of this species are much more genetically diverse (six distinct clades) and some of the populations are allopatric and others sympatric. They probably diverged and expanded during the last few glaciations. Genetic discontinuities were detected among localities that are now separated by gaps in the distribution. Boundaries (mountains or farmland) separate the populations into three groups: (1) Moravia and Slovakia, (2) the lower Vistula Valley in northern Poland and (3) south-eastern Poland together with western Ukraine. Evidence for recent gene flow was found only among populations from south-eastern Poland and western Ukraine, and between these two groups. One population from northern Poland was surprisingly related to populations in southern Poland, which may be due to extinction of intermediate populations. |
Infestation of Narcissus poeticus by a scathophagid fly, Norellia melaleuca (Diptera: Scathophagidae)Giuseppe CHICHIRICCÒEur. J. Entomol. 107 (4): 677-680, 2010 | DOI: 10.14411/eje.2010.075 A little-known scathophagid fly is reported infesting the flowers and scapes of Narcissus poeticus growing in the Italian Central Apennines (AQ). This insect bores through the flower bud and lays an egg on the tepals. Both pistil and scape parenchymatous tissues provide the larva with nutrition, and the hollow stem a safe site for its metamorphosis. Infestation by this insect prevents the ovules from being fertilized as the larvae feed on the tisues in the style and so prevent the growth of pollen tubes. |
A review of the European species of Phradis (Hymenoptera: Ichneumonidae: Tersilochinae), with a description of a new species from SpainAndrey I. KHALAIM, Santiago BORDERA, Alexander RODRÍGUEZ-BERRÍOEur. 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. |
Taxonomical revision of the Longitarsus capensis species-group: An example of Mediterranean-southern African disjunct distributions (Coleoptera: Chrysomelidae)Maurizio BIONDI, Paola D'ALESSANDROEur. J. Entomol. 105 (4): 719-736, 2008 Southern-African Longitarsus capensis species-group, which is closely related to the Mediterranean anchusae species-group is revised. L. capensis species-group includes 15 species, 8 of which are new to science: Longitarsus capensis Baly, 1877, L. cedarbergensis Biondi, 1999, L. luctuosus Biondi, 1999, L. lugubris Biondi, 1999, L. melanicus Biondi, 1999, L. neseri Biondi, 1999, L. transvaalensis Biondi, 1999, L. afromeridionalis sp.n., L. debiasei sp.n., L. grobbelaariae sp.n., L. hexrivierbergensis sp.n., L. malherbei sp.n., L. piketbergensis sp.n., L. rouxi sp.n., and L. sudafricanus sp.n. A key to all the species is presented as well as line drawings of male and female genitalia, scanning electron micrographs of some diagnostic morphological characters, and auto-ecological and zoogeographical data. Relationships within the capensis-group, and between the anchusae and capensis-group are better defined and hypotheses explaining the separate distributions of Mediterranean and south African anchusae and capensis species-groups proposed. Finally, the host-plant shift from native Lobostemon spp. to the introduced plant Echium plantagineum L. shown by some species of the capensis group is also discussed. |
Isolation and characterization of oligomerization domain I and II coding regions of doublesex genes in agricultural fruit flies (Diptera: Tephritidae)Rattiya PERMPOON, Sujinda THANAPHUMEur. J. Entomol. 107 (1): 121-126, 2010 | DOI: 10.14411/eje.2010.015 Bactrocera fruit flies are ranked among the most destructive pests of the worldwide fruit and vegetable trades. Coding regions of two oligomerization domains within doublesex (dsx) genes were determined in Bactrocera dorsalis (oriental fruit fly) and B. correcta (guava fruit fly). Resulting sequences revealed a high degree of similarity at both nucleotide and putative amino acid levels in the genus Bactrocera. Conservation of the DNA-binding DM motif and several known molecular features within the domains suggest a presence of strong purifying selection on the DSX proteins. Topology of the phylogenetic gene trees and deduced amino acid substitution patterns suggest that the coding region sequences of the two domains are diversified in concert parallel with the species differentiation. |
BOOK REVIEW: Settele J., Shreeve T., Konvicka M. & Van Dyck H. (eds): ECOLOGY OF BUTTERFLIES IN EUROPE.T. KADLEC, V. JARO©ÍKEur. J. Entomol. 107 (2): 228, 2010 | DOI: 10.14411/eje.2010.030 Cambridge University Press, Cambridge, UK, 2009, xii + 513 pp. Paperback ISBN 978-052-176-6975, price USD 75.00, hardback ISBN 978-052-174-7592, price USD 160.00. |
BOOK REVIEW: Schintlmeister A.: Palaearctic Macrolepidoptera. Vol. 1: Notodontidae.Z. FRIC, A. PAVLÍKOVÁEur. J. Entomol. 107 (1): 80, 2010 | DOI: 10.14411/eje.2010.010 Apollo Books, Stenstrup, 2008, 482 pp., ISBN 978-87-88757-77-4. Price EUR 140.00, USD 196.00. |
Rhythmic oscillations of α-amylase protein and its enzymatic activity levels in Drosophila melanogaster (Diptera: Drosophilidae)Marcin A. CIUK, Piotr BEBAS, Bronislaw CYMBOROWSKIEur. J. Entomol. 106 (4): 519-528, 2009 | DOI: 10.14411/eje.2009.065 In this report, we show that α-amylase activity is rhythmic in the wild-type fruit fly Drosophila melanogaster, and that this rhythm exhibits the properties of a clock output. Moreover, the rhythm of amylase activity is accompanied by fluctuations in the Amy protein level under 12L : 12D conditions. A strong sexual dimorphism is evident in the oscillations of Amy protein and enzymatic activity. Under light : dark (LD) conditions on the control diet, CantonS wild-type Drosophila melanogaster exhibit a bimodal rhythm of amylase activity, particularly of the AmyD3 (Amy3) isoform, with morning and evening peaks. Under these conditions, Amy protein levels also oscillate significantly, again more strongly for the Amy3 isoform than Amy1 (Amy1). A robust oscillation of Amy3 and Amy1 activity is also observed under DD conditions for both sexes. In constant light (LL) the rhythms dampen out, particularly in the males. A high level of dietary glucose causes an overall decrease in the amplitudes of the rhythmic oscillations of amylase activity, but the processes are nevertheless rhythmic, with peak activities at Zt8 for the females, and at Zt0 for the males in LD. In constant darkness (DD) the rhythms are maintained. Mutants lacking a functioning oscillator, per01, exhibit a slight photoperiodicity in LD, with a decrease in amylase activity in both males and females during the late night in LD, but no rhythmic oscillations in DD. |
Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotationAlberto BRESSAN, Werner E. HOLZINGER, Benoit NUSILLARD, Olivier SÉMÉTEY, Frédéric GATINEAU, Mauro SIMONATO, Elisabeth BOUDON-PADIEUEur. J. Entomol. 106 (3): 405-413, 2009 | DOI: 10.14411/eje.2009.052 Cixiid planthoppers have been shown to vector phloem-limited prokaryotes associated with plant diseases world-wide. In eastern France, an emerging disease of sugar beet called syndrome "basses richesses" has been associated with phloem-restricted bacteria transmitted by a cixiid planthopper within the genus Pentastiridius. Early investigation suggested the species being Pentastiridius beieri. On the basis of a morphological and phylogenetic study we report the identification of the planthopper as Pentastiridius leporinus. Furthermore we report some biological traits of the species, which shows a surprising ecological adaptation to an annual cropping rotation sugar beet-winter cereals. |
The effect of corazonin on heartbeat reversal in pupae of the tobacco hornworm, Manduca sexta (Lepidoptera: Sphingidae)Karel SLÁMAEur. J. Entomol. 101 (4): 513-521, 2004 | DOI: 10.14411/eje.2004.073 Heartbeat reversal patterns have been monitored in the body of diapausing pupae of M. sexta 2 h before and 3 h after the injections of [Arg7]-corazonin, using noninvasive thermographic and optocardiographic methods. Large dosages (10-6 M final concentrations of corazonin in the body) caused almost immediate, adrenaline-like enhancement of the anterograde heartbeat. During the relatively short, acute phase of the tachycardia induced by corazonin, the systolic anterograde contractions of the heart increased in average from 10.5 to 24 pulses per min, culminating at 2.5 min after the injections. Duration of the acute period of tachycardia was only 7 to 20 min, which was followed by a period of slightly elevated, residual anterograde heartbeat which persisted occasionally for 1 to 3 h. Smaller dosages of corazonin (10-7M concentrations in the body) occasionally also produced a less intensive cardiotropic effect, while the more diluted samples were completely inactive. In pupae of the beetle T. molitor, injections of corazonin (10-6 M in the body) had no effect on the rate of in vivo heartbeat at all. Pharmacological analysis of the effects of corazonin in M. sexta indicated that the cardiostimulating effects of corazonin did not conform with the expected action of a peptidic neurohormone. A possibility that these effects might be artifacts produced by the low molecular breakdown products of corazonin has been discussed. |
Ecological factors determining the density-distribution of Central European dragonflies (Odonata)Filip HARABI©, Aleą DOLNÝEur. J. Entomol. 107 (4): 571-577, 2010 | DOI: 10.14411/eje.2010.066 Habitat specificity is the most important factor affecting the regional distribution of dragonflies. Nevertheless, species with the highest specificity are not always the scarcest. Several important determinants of dragonfly density-distribution relationships were identified. Altitude preference and altitude range are significantly associated with dragonfly distribution. Some of the species that are habitat specialists but occur over a wide range of altitudes should be classified as rare but not endangered. This very simple principle is based on the assumption that habitat specialists have a very limited number of suitable biotopes. Obviously, dragonflies with a marginal distribution prefer a narrow range of altitudes (especially in terms of temperature limitation) and biotopes (effect of biogeography, marginality). Surprisingly, there is no "critical" life stage that is significantly associated with the regional distribution of dragonflies, although most species spend most time in the larval stage. Knowledge of the dispersal ability of particular species is limited, although it could significantly affect species survival and distribution. |
Performance of a predatory ladybird beetle, Anegleis cardoni (Coleoptera: Coccinellidae) on three aphid speciesOMKAR, Gyanendra KUMAR, Jyotsna SAHUEur. J. Entomol. 106 (4): 565-572, 2009 | DOI: 10.14411/eje.2009.071 Qualitative and quantitative differences in prey are known to affect the life histories of predators. A laboratory study was used to evaluate the suitability of three aphid prey, Aphis gossypii, Aphis craccivora and Lipaphis erysimi, for the ladybird beetle, Anegleis cardoni (Weise). Development was fastest on A. gossypii followed by A. craccivora and L. erysimi. Percentage pupation, immature survival, adult weight and the growth index were all highest when reared on A. gossypii and lowest on L. erysimi. Similarly, oviposition period, lifetime fecundity and egg viability were all highest on a diet of A. gossypii, lowest on L. erysimi and intermediate on A. craccivora. Age-specific fecundity functions were parabolic. Adult longevity, reproductive rate and intrinsic rate of increase were all highest on A. gossypii and lowest on L. erysimi. Life table parameters reflected the good performance on A. gossypii and poor performance on L. erysimi. Estimates of individual fitness values for the adults reared on A. gossypii and A. craccivora were similar and higher than that of adults reared on L. erysimi. Thus, the three species of aphid can all be considered essential prey for A. cardoni. |
Phenotypic plasticity in sperm traits in scorpionflies (Mecoptera: Panorpidae): Consequences of larval history and seasonality on sperm length and sperm transferAndreas VERMEULEN, Sierk ENGELS, Leif ENGQVIST, Klaus Peter SAUEREur. J. Entomol. 106 (3): 347-352, 2009 | DOI: 10.14411/eje.2009.042 We examined effects of seasonality, larval food availability and larval rearing density on sperm length, sperm transfer rates and body size in the bivoltine scorpionfly Panorpa vulgaris. Males of the first annual generation were larger and had larger sperm. Comparing individuals of two summer generations showed that adult males resulting from group bred, ad libitum fed larvae were larger but had smaller sperm than males resulting from singly kept, food deprived larvae. Thus, sperm size is not a simple function of body size. Instead, we suggest that sperm size modification was caused by varying rearing densities. Group bred individuals produced smaller sperm but transferred at higher rate. This indicates a trade-off between sperm number and sperm size as predicted by evolutionary models of sperm production. Given the strong influence of larval history in our present work, we recommend that future studies investigating the consequences of varying sperm competition risk or intensity on male gametic strategies should also control for larval history in order to avoid distorting effects. |
BOOK REVIEW: Braby M.F.: The Complete Field Guide to Butterflies of Australia.J. JARO©, K. SPITZEREur. J. Entomol. 102 (1): 124, 2005 | DOI: 10.14411/eje.2005.019 CSIRO Publishing, Collingwood, VIC., 2004, 339 pp. (paperback). |
An improved method for the culture of wing discs of the wingless bagworm moth, Eumeta variegata (Lepidoptera: Psychidae)Shuhei NIITSU, Saori LOBBIAEur. J. Entomol. 107 (4): 687-690, 2010 | DOI: 10.14411/eje.2010.078 Adults of the wingless bagworm moth, Eumeta variegata, show remarkable sexual dimorphism. Final-instar larvae of the male have invaginated wing discs, whereas those of the female are rudimentary. To determine the best method for culturing the wing discs of E. variegata, which in both sexes are attached to the larval integument, two methods of culturing the larval wing discs are compared. Initially, a stationary culture was used. In these cultures necrotic cells and degeneration of wing discs of males were sporadically observed. By contrast, many small vacuoles were observed in the female wing rudiment under these conditions. In order to overcome some of the problems associated with stationary culture, rotating culture was used and resulted in the wing discs of males and females remaining in good condition. A histological analysis revealed that the wing disc morphology was normal when they were cultured in this way. These results indicate that rotating the culture medium is the better procedure for studying the action of hormones on the differentiation and metamorphosis of reduced wing rudiments in E. variegata. |
Multitrophic interactions among plants, aphids, alternate prey and shared natural enemies - a reviewEdward W. EVANSEur. J. Entomol. 105 (3): 369-380, 2008 | DOI: 10.14411/eje.2008.047 Given the generalist tendencies of most predatory arthropods, it is widely thought that their impact on a particular prey species in a given habitat (e.g., an insect pest in a crop) will depend frequently on the local availability of other prey (which for omnivorous predators, can include plant resources, such as fruit and pollen). Thus, from a slightly different perspective, aphids, other herbivorous insects, and plants often may interact indirectly by sharing natural enemies. Such interactions may be either negative or positive, as in the concepts of apparent competition and apparent mutualism, and may therefore have variable impact on the herbivores' host plants as well. I examine the different mechanisms for such indirect effects among herbivores as explored in the experimental literature. An impressive collective effort by numerous researchers recently has expanded considerably our empirical base of support for a variety of hypothesized mechanisms; aphids stand out as the most commonly studied subjects in research on these mechanisms. I therefore focus especially on the recent literature of cases involving aphids interacting indirectly with other prey for generalist predators. My remarks are organized by considering how the availability of alternate prey may alter functional and numerical (aggregative and reproductive) responses of predators to focal prey density. Although the distinctions among these different classes of predator responses and the associated indirect effects are often blurred and scale-dependent, this classification remains useful for organizing the diverse ways in which aphids have been found to participate in indirect interactions among prey as mediated by predators. Collectively, the results of the numerous studies reviewed here suggest that many such indirect interactions likely occur frequently in natural settings, with consequences ultimately for host plant performance. |
Intrasexual fighting and mounting by females of the horned beetle Trypoxylus dichotomus (Coleoptera: Scarabaeidae)Yutaka IGUCHIEur. J. Entomol. 107 (1): 61-64, 2010 | DOI: 10.14411/eje.2010.007 Although females of the horned beetle, Trypoxylus dichotomus septentrionalis, have only small horns they often fight over access to feeding sites by head-butting each other. In addition, they sometimes show intrasexual mounting. In this study 82 females of different sizes were used to determine the relationship between fighting and mounting. Large females more often won fights and so gained access to food than small females. In contrast, small females more often mounted large females and then gained access to food than large females. These results suggest that female mounting may function as a tactic for reducing intrasexual fighting between small and large females. |
The use of RAPD markers to detect genetic patterns in Aleurodicus dispersus (Hemiptera: Aleyrodidae) populations from the Canary IslandsCarmen CALLEJAS, Francisco J. BEITIA, Antonio GOBBI, Ana VELASCO, M. Dolores OCHANDOEur. J. Entomol. 102 (2): 289-291, 2005 | DOI: 10.14411/eje.2005.040 Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae), a highly polyphagous species, has since the 90's been an important pest of ornamentals and tropical crops in the Canary Islands. In this study the RAPD-PCR technique was used to study the genetic structure of this whitefly in this archipelago. A total of 68 different bands were scored in seven populations using six primers for amplification. No differences in RAPD patterns were found among populations from different islands of the Canaries. These findings indicate a very high genetic similarity among populations and low level of genetic variability and support a single colonization event by few A. dispersus whiteflies and recent dispersion throughout the archipelago. |
Alteration of sex-related developmental modules: A case of "feminized" male wing morphology in Creobroter gemmatus (Mantodea: Hymenopodidae)Olivier BÉTHOUXEur. J. Entomol. 107 (1): 133-135, 2010 | DOI: 10.14411/eje.2010.018 A particular case of the alteration of the organization of a developmental module is presented, viz. mixed gynandromorphism in Creobroter gemmatus, in which a male exhibits the usual fore- and hind wing venation and shape of its sex, but patterns of coloration typical of females. Homologies between corresponding areas of the fore- and hind wings are suggested. "Feminization" is defined as the occurrence of traits typical of the female phenotype in a male, and is suggested as a plausible way in which insect wing morphology may be transformed. |
Revision of the Iteaphila setosa group (Diptera: Empididae)Igor V. SHAMSHEV, Bradley J. SINCLAIREur. J. Entomol. 106 (3): 441-450, 2009 | DOI: 10.14411/eje.2009.055 Six species are identified in the Iteaphila setosa group [I. arundela sp. n., I. caucasica sp. n., I. italica Loew, 1873, I. kubaniensis sp. n., I. merzi sp. n., I. setosa (Bezzi, 1924)]. This species group is distributed from southern England in the west, through southern Europe and northern Africa, to the Caucasus and Middle Asia (Uzbekistan). |
Laboratory study of the effects of leek lectin (APA) in transgenic tobacco plants on the development of cotton leafworm Spodoptera littoralis (Lepidoptera: Noctuidae)Amin SADEGHI, Guy SMAGGHE, Esmeralda JURADO-JÁCOME, Willy J. PEUMANS, Els J.M. VAN DAMMEEur. J. Entomol. 106 (1): 21-28, 2009 | DOI: 10.14411/eje.2009.003 Transgenic tobacco plants expressing the Allium porrum L. (leek) agglutinin (called APA) under the control of the 35S constitutive promoter were tested for their insecticidal activity against the cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae). Southern blot and PCR analysis confirmed that the APA gene was integrated into the plant genome. Northern and Western blots as well as semi-quantitative agglutination assays revealed lectin expression at various levels in the transgenic lines. Biochemical analyses indicated that the recombinant APA has the same molecular structure as the native lectin. Native and recombinant lectin have the same N-terminal amino acid sequence. Bioassays using detached leaves from transgenic tobacco plants demonstrated that the ectopically expressed APA significantly (p < 0.05) reduced the weight gain of 2nd-instar larvae of S. littoralis. This inhibitory effect was observed throughout the experiment and on day 11 the caterpillars fed on transgenic tobacco leaves were 25-30% lighter in weight than the control caterpillars fed on wild type plants. In addition the lectin retarded the development of the larvae and metamorphosis, reduced pupal weight and increased mortality rate. These findings suggest that APA is a suitable insect resistance protein for integrating into plant genomes for controlling S. littoralis. |
Karyotype and male meiosis in Spartocera batatas and meiotic behaviour of multiple sex chromosomes in Coreidae (Heteroptera)María José FRANCO, María José BRESSA, Alba GRACIELA PAPESCHIEur. J. Entomol. 103 (1): 9-16, 2006 | DOI: 10.14411/eje.2006.002 The Coreidae (Heteroptera) have holokinetic chromosomes and during male meiosis the autosomal bivalents segregate reductionally at anaphase I while the sex chromosomes do so equationally. The modal diploid chromosome number of the family is 2n = 21, with a pair of m-chromosomes and an X0/XX sex chromosome system. A 2n = 24/26 (male/female) and an X1X20/X1X1X2X2 sex chromosome system were found in Spartocera batatas (Fabricius). C-banding and fluorescent-banding revealed the presence of AT-rich heterochromatic bands medially located on all the autosomes, and one telomeric band on both the X1 and X2 chromosomes. This banding pattern differed from the telomeric heterochromatin distribution found in most other heteropteran species. The X1 and X2 chromosomes were intimately associated during male meiosis and difficult to recognize as two separate entities. Based on a comparison with the behaviour of sex chromosomes in other coreids and other heteopterans with multiple sex chromosomes it is suggested that the particular behaviour of X1 and X2 chromosomes in coreid species with multiple sex chromosome systems evolved as an alternative mechanism for ensuring the proper segregation of the sex chromosomes during meiosis. |
Eothalassius, a new genus of parathalassiine flies (Diptera: Empidoidea: Dolichopodidae) from Southeast Asia and Papua New GuineaIgor V. SHAMSHEV, Patrick GROOTAERTEur. J. Entomol. 102 (1): 107-118, 2005 | DOI: 10.14411/eje.2005.016 A new genus of parathalassiine-like flies, Eothalassius gen. n., and two new species, Eothalassius platypalpus sp. n. (type species), E. gracilis sp. n., are described from the coasts of Southeast Asia and Papua New Guinea. The phylogenetic relationships of the new genus with other genera assigned to Parathalassiinae and Dolichopodidae are discussed. |
The ant-associations and diet of the ladybird Coccinella magnifica (Coleoptera: Coccinellidae)John J. SLOGGETT, Wolfgang VÖLKL, Werner SCHULZE, J. Hinrich G.v.d. SCHULENBURG, Michael E.N. MAJERUSEur. J. Entomol. 99 (4): 565-569, 2002 | DOI: 10.14411/eje.2002.075 The ladybird Coccinella magnifica is typically considered to be myrmecophilous, and primarily associated with the Formica rufa group of wood ants. It is regularly associated with ants of the F. rufa group in north-western Europe. The very limited data on the habitat preference of C. magnifica in the southern and eastern parts of its range indicate that its ant-associations change and that it may even be non-myrmecophilous in this region. C. magnifica might consist of geographically restricted species or semispecies, on the basis of its geographical variation in ant-association. Laboratory and field observations on north-western myrmecophilous populations C. magnifica appear to indicate it is a generalist predator of aphids. Coccinella magnifica's potential dietary breadth is similar to that of its congener Coccinella septempunctata, which has been used as a model of C. magnifica's non-myrmecophilous ancestor in evolutionary studies. |
The range of insect dormancy responsesHugh V. DANKSEur. J. Entomol. 99 (2): 127-142, 2002 | DOI: 10.14411/eje.2002.021 Insect dormancy responses, in the broad sense of modifications of development, are examined from a general perspective. The range of responses is extraordinarily wide because environments are diverse, different taxa have different evolutionary histories, adaptations are needed for both seasonal timing and resistance to adversity, and not only development but also many other aspects of the life-cycle must be coordinated. Developmental options are illustrated by examining the wide range of ways in which development can be modified, the fact that each individual response consists of several components, and the different potential durations of the life-cycle. The concepts of alternative life-cycle pathways (chosen according to current and likely future environmental conditions) and of active and passive default responses are treated. Also introduced are aspects of variation and trade-offs. |
Cytogenetic differences between Peritelus familiaris and Centricnemus leucogrammus (Coleoptera: Curculionidae: Entiminae: Peritelini)Dorota LACHOWSKA, Maria ROŻEK, Milada HOLECOVÁ, Lukasz KAJTOCHEur. J. Entomol. 103 (3): 687-690, 2006 | DOI: 10.14411/eje.2006.089 Differences in the karyology of two species, Centricnemus leucogrammus and Peritelus familiaris (Coleoptera: Curculionidae), were investigated in order to elucidate their taxonomic position of the taxa. Previously both species were placed in one genus whereas the latest taxonomic revision puts them in separate genera. Cytogenetic analysis of P. familiaris and C. leucogrammus showed significant differences in karyotype structure and confirmed their present taxonomic status. The diploid set of C. leucogrammus consists of 22 chromosomes with a fundamental number of arms (FN) of 45 and little variation in morphology and length. Peritelus familiaris has 24 chromosomes with FN of 47 and a more diverse karyotype. The karyotype evolution might have occured by centric fissions of autosomes. At pachytene and diplotene in spermatocytes, each chromosome bivalent showed a small band of pericentric heterochromatin. The bands were hardly visible or undetectable in other stages of spermatogenesis, namely mitotic metaphase, diakinesis, metaphase I and II. The nucleolar organizer regions (NORs) were active at premeiotic stages and early meiosis, but invisible at meiotic metaphase I, metaphase II, and mitotic metaphase. These results indicate the usefulness of cytogenetic methods in taxonomic evaluations. |
Response of Coccinella septempunctata and Menochilus sexmaculatus (Coleoptera: Coccinellidae) to their aphid prey, Lipaphis erysimi (Hemiptera: Aphididae) in rapeseed-mustardJogender S. RANAEur. J. Entomol. 103 (1): 81-84, 2006 | DOI: 10.14411/eje.2006.013 During a three year study in rapeseed-mustard crop, the response of two ladybird species, Coccinella septempunctata and Menochilus sexmaculatus was dependent upon density and time of appearance of their prey. Mustard aphid, Lipaphis erysimi appeared during the second (2000 and 2001) and last (2002) week of January. Aphid appearance was highly dependent on the phenological stage of the host plant. It appeared earlier in rapeseed, Brassica campestris var. BSH-1 than mustard, Brassica juncea var. RH-30. The ladybird beetle's eggs were observed in the last week of January, 4-5 weeks before the maximum aphid population. A correlation between aphid number and the abundance of ladybirds' life stages (egg, larva and beetle) on these host plants revealed that the egg and larval density was positively correlated to aphid numbers. Adult beetles, however, did not show significant positive correlation with aphid numbers during all the three years of study. Coccinella septempunctata was more abundant than Menochilus sexmaculatus in these crops. Menochilus sexmaculatus population disappeared earlier than Coccinella septempunctata which was abundant until end of the crop season. |
The effect of starvation on the metabolic rate and microanatomy of Galumna elimata (Acari: Oribatida)Jan HUBERT, Vladimír ©USTREur. J. Entomol. 98 (3): 265-275, 2001 | DOI: 10.14411/eje.2001.043 The physiological parameters mortality, mass, oxygen consumption and amylase activity, and microanatomical features of the digestive tract, mesenchym and reproductive organs were used to characterise starvation in Galumna elimata. The mites were reared in sterilised plastic vials containing moistened zeolite at 25°C and a 12:12 photoperiod. The control group was kept under the same conditions, but pieces of bark covered with the green bark alga, Desmococcus vulgaris (syn. Protococcus viridis), were added as food for the mites. The physiological parameters were recorded after 21 days, and the microanatomical after 21 and 42 days. The guts of the starved mites were empty or filled with mucoid substances, while the guts of control mites contained food boli formed from algal cells. The mortality was significantly higher in starved animals. The mortality after 42 days of starvation was higher in males than females. The fresh mass of starved individuals significantly decreased while the water proportion content of their body tissues increased. Oxygen consumption of the starved mites was lower. Starvation did not influence the activity of amylase. Glycogeneous granulae were characteristically absent, and mucoid substances present in the guts of mites starved for 21 days. The activity of mesenteral and caecal cells, proventricular glands and cells of salivary glands was reduced after 42 days of starvation. The cells of the seminal vesicles were reduced and contained no spermatic cells in males starved for 42 days. Starved females probably resorbed immature oocytes, but had eggs in their oviducts. Starvation induces ovovivipary or larvipary in Galumna elimata. |
Hedyselmis opis: Description of the larva and its phylogenetic relation to Graphelmis (Coleoptera: Elmidae: Elminae)Fedor ČIAMPOR Jr., Ignacio RIBERAEur. J. Entomol. 103 (3): 627-636, 2006 | DOI: 10.14411/eje.2006.084 The riffle beetle genus Hedyselmis Hinton, 1976 includes two species from the Malay Peninsula, with adults with a highly deviating morphology. Its phylogenetic relationships are unclear, although it has been hypothesized to be related to Graphelmis Delève, 1968, a large genus widely distributed in the Oriental and East Palaearctic regions. In this paper the larva of H. opis Hinton, 1976 is described based on material collected in the Cameron Highlands (Malaysia) and the conspecificity with co-existing adults tested using sequences of one nuclear (5' end of 18S rRNA) and three mitochondrial gene fragments (5' end of the large ribosomal unit + tRNAleu + 5' end of the NADH dehydrogenase subunit 1; 5' end of cytochrome c oxidase subunit I; and a fragment of cytochrome b) with a total of ca. 2,600 bp. This is the first example of the use of molecular data to match different life stages within the family Elmidae. The larva of H. opis has a subcylindrical body typical of many other elmid genera; abdominal segments 1-7 with preserved pleura; and ninth segment with oval operculum. The last instar larvae have clearly visible prominent spiracles on mesothorax and abdominal segments 1-8. The phylogenetic position of Hedyselmis in relation to Graphelmis was investigated using molecular data for three species of Graphelmis plus a selection of other Elmidae genera. Hedyselmis opis is nested within Graphelmis, confirming their close relationship and suggesting that their status requires taxonomic revision. |
Regular periods of abdominal contractions recorded from larvae of the bumblebee, Bombus terrestris (Hymenoptera: Apidae)Marika MÄND, Aare KUUSIK, Ants-Johannes MARTIN, Ingrid H. WILLIAMS, Anne LUIK, Reet KARISE, Luule METSPALU, Külli HIIESAAREur. J. Entomol. 103 (2): 319-322, 2006 | DOI: 10.14411/eje.2006.041 Using an opto-cardiograph combined with an infrared gas analyzer regular bouts of abdominal contractions were recorded from last instar larva of Bombus terrestris. The rate of CO2 release was about 0.7 ml g-1 h-1. The bouts of contractions were of two types: weak extracardiac pulsations and vigorous pumping. The frequencies of pulsations and pumping were 25-35 per min and 8-12 per min, respectively. Bouts of extracardiac pulsations and abdominal pumping were independent of each other and sometimes overlapped. Cardiac contractions (heartbeats) were continuous (57-63 pulses/min). This study suggests that the periodically occurring abdominal contractions play an essential role in respiration and/or in haemolymph circulation in larvae of B. terrestris. |