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Wolbachia infection in Trissolcus species (Hymenoptera: Scelionidae)Nurper GUZ, Erhan KOCAK, A. Emre AKPINAR, M. Oktay GURKAN, A. Neset KILINCEREur. J. Entomol. 109 (2): 169-174, 2012 | DOI: 10.14411/eje.2012.022 Wolbachia is a maternally transmitted intracellular symbiont which causes reproductive distortions in the arthropods it infects. In recent years there has been an increasing interest in using Wolbachia as a potential tool for biological control by genetic manipulation of insect pests. In the present paper we report Wolbachia infection in several Trissolcus wasps (Hymenoptera: Scelionidae) which are important egg parasitoids of the sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutellaridae). We used DNA sequence data for a gene encoding a surface protein of Wolbachia (wsp) not only to confirm Wolbachia infection but also to discriminate Wolbachia strains. Phylogenetic analyses indicated that Wolbachia strains in Trissolcus species were closely related to one another and belonged to supergroup B. Determination of the infection status of various populations, the possible role of Wolbachia in causing the incompatibility and knowledge of the reproductive compatibility of Trissolcus populations is important for the success of parasitoids in sunn pest management. |
BOOK REVIEW: Kudrna O., Harpke A., Lux K., Pennerstorfer J., Schweiger O., Settele J. & Wiemers M.: Distribution Atlas of Butterflies in Europe.Z. FRICEur. J. Entomol. 109 (2): 293-294, 2012 | DOI: 10.14411/eje.2012.038 Kudrna O., Harpke A., Lux K., Pennerstorfer J., Schweiger O., Settele J. & Wiemers M.: Distribution Atlas of Butterflies in Europe. Geselschaft für Schmetterlingsschutz e.V., Halle, 2011, 576 pp., ISBN 978-3-938249-70-3. Price EUR 65.00. |
Development of novel microsatellite markers for a specialist species of Lepidoptera, Boloria aquilonaris (Nymphalidae), based on 454 sequencesSofie VANDEWOESTIJNE, Camille TURLURE, Michel BAGUETTEEur. J. Entomol. 109 (1): 129-134, 2012 | DOI: 10.14411/eje.2012.016 Microsatellites are the most common markers used in population and conservation genetic studies. However, their isolation is laborious and expensive. In some taxa, such as Lepidoptera, it is particularly difficult to isolate microsatellite markers due to the high similarity of the flanking regions of different loci and the presence of null alleles. Here we isolated microsatellites of the endangered butterfly Boloria aquilonaris using 454 GS-FLX Titanium pyro-sequences of biotin enriched DNA libraries and tested the success of cross-amplification on the sister-species B. eunomia. Fifteen polymorphic microsatellite loci were isolated in B. aquilonaris using initially 101 stringently designed primer pairs. Unlike in many other studies of microsatellite isolation in Lepidoptera, few null alleles were detected and only at very low frequencies. Additionally, the raw data set can still be used for the isolation of other microsatellite loci. None of the selected polymorphic loci for B. aquilonaris gave clear banding patterns for B. eunomia, although about 15 other loci gave promising banding patterns for the latter species. Low intra- and inter-specific transferability of developed markers in this study also lends support to the hypothesis that the evolution of the genome of Lepidoptera is dissimilar from that of other organisms. |
How many species are there in the subgenus Bursaphis (Hemiptera: Sternorrhyncha: Aphididae)? CO-I evidenceRimantas RAKAUSKAS, Jurga TURÈINAVIÈIENĖ, Jekaterina BA©ILOVAEur. J. Entomol. 108 (3): 469-479, 2011 Species-level problems in the Aphis (Bursaphis) complex are reconsidered based on the partial sequences of the mitochondrial cox1 gene together with morphological and ecological data. This indicates that the American species A. oenotherae is a complex of four species (A. oenotherae, A. holoenotherae, A. costalis and A. neomexicana) and the taxonomic status of the species couples A. varians - A. manitobensis and A. epilobii - A. grossulariae require further clarification. Aphis sp. (USA: California, Oregon) of Blackman & Eastop (2006, p. 415) deserves the status of a species provided there is information on its host association and life cycle. Partial cox1 sequences might be misleading when used as standard DNA barcodes of aphid species of the subgenus Bursaphis. |
Determination of female-biased sexual size dimorphism in moths with a variable instar number: The role of additional instarsToomas ESPERK, Toomas TAMMARUEur. J. Entomol. 103 (3): 575-586, 2006 | DOI: 10.14411/eje.2006.078 While the ultimate causes and adaptive significance of sexual size dimorphism (SSD) have been extensively studied, the developmental mechanisms behind this phenomenon have received little attention. Going through an additional larval instar may form a specific way of achieving SSD in arthropods. In the present study, the mechanisms of SSD determination of two lymantriid moths, with marked SSD, were studied. In both species, females tended to go through an additional instar compared to males, and form pupae that were more than twice the weight of the males. To reveal the role of an extra instar, larval growth was monitored in the laboratory and the growth parameters were analysed as dependent on sex and developmental type (number of instars). Prolongation of growth by means of adding an additional larval instar in females turned out to be the key mechanism in the determination of the highly female-biased SSD in the species studied. There is thus a developmental mechanism available that permits achieving a larger size by means of extending the growth period. This provides evidence against constraint-based evolutionary explanations for body sizes in insects. There was no considerable accumulation of SSD during earlier larval life when females went through more instars than males. In contrast, in those cases in which males and females had the same number of instars, SSD accumulated gradually during the course of several larval instars. Longer growing period turned out to be a crucial mechanism leading to the female-biased SSD even when instar number did not differ between sexes, although higher instantaneous relative growth rates of females also played a complementary role in the latter case. Within sexes, an additional instar was characteristic of initially smaller larvae, as predicted by the "threshold size" hypothesis. |
The genus Amiota (Diptera: Drosophilidae) from Hengduan Mountains, southwestern ChinaWenxia ZHANG, Hongwei CHENEur. J. Entomol. 103 (2): 483-495, 2006 | DOI: 10.14411/eje.2006.062 A total of 39 Amiota species are found from the southern portion of Hengduan Mountains, southwestern China, including 12 new species: A. gaoi sp. n., A. gracilenta sp. n., A. multispinata sp. n., A. yifengi sp. n., A. angustifolia sp. n., A. bacillia sp. n., A. biacuta sp. n., A. cultella sp. n., A. deltoidea sp. n., A. pianmensis sp. n., A. setosa sp. n. and A. bifoliolata sp. n. A key to all the studied species from Hengduan Mountains is provided. |
BOOK REVIEW: Jendek E. & Grebennikov V.: Agrilus (Coleoptera, Buprestidae) of East Asia.S. BÍLÝEur. J. Entomol. 109 (2): 228, 2012 | DOI: 10.14411/eje.2012.029 Jendek E. & Grebennikov V.: Agrilus (Coleoptera, Buprestidae) of East Asia. Jan Farkaè, Prague, 2011, 362 pp. ISBN 978-80-903590-6-2 (HB). Price EUR 120.00. |
Increasing patch area, proximity of human settlement and larval food plants positively affect the occurrence and local population size of the habitat specialist butterfly Polyommatus coridon (Lepidoptera: Lycaenidae) in fragmented calcareous grasslandsZuzanna M. ROSIN, Piotr SKÓRKA, Magdalena LENDA, Dawid MORON, Tim H. SPARKS, Piotr TRYJANOWSKIEur. J. Entomol. 108 (1): 99-106, 2011 | DOI: 10.14411/eje.2011.013 Which factors influence the occurrence, population size and density of species in fragmented habitat patches are key questions in population and conservation ecology. Metapopulation theory predicts that larger and less isolated habitat patches should positively influence species occurrence and population size. However, recent studies have shown that habitat quality, human activity and permeability of the landscape surrounding habitat patches may be also important. In this paper we test the relative effects of habitat patch characteristics, human settlement and landscape permeability on the occurrence, local population size and density of the Chalk-hill Blue Polyommatus coridon a charismatic butterfly inhabiting calcareous grasslands in a fragmented landscape in southern Poland. Patch occupancy rate (corrected for the butterfly detection probability) was 0.45. Habitat patch area, proximity of human settlement and cover of larval food plants positively affected occurrence of the Chalk-hill Blue. Local population size of the Chalk-hill Blue was positively affected by patch area and proximity of human settlement, and negatively by patch isolation. Local density was higher in patches located close to human settlement. Our study is one of the few showing a positive effect of human settlement on a grassland specialist butterfly although the mechanism hidden behind this phenomenon is unknown and requires further examination. In order to maintain local populations of the Chalk-hill Blue in southern Poland, conservation action should be focused on large, closely connected calcareous grasslands. Moreover, extensive management of this habitat should be maintained by local inhabitants who are better placed to undertake such work. |
BOOK REVIEW: Kluge N.: THE PHYLOGENETIC SYSTEM OF EPHEMEROPTERA.T. SOLDÁNEur. J. Entomol. 104 (2): 351-352, 2007 | DOI: 10.14411/eje.2007.052 Kluwer Academic Publishers, Dordrecht/Boston/ London, 2004, xiii + 442 pp. ISBN: 1-4020-1974-2 (hardcover). Price EUR 220.00, USD 242.00, GBP 152.00. |
An attempt to reconstruct the natural and cultural history of the granary weevil, Sitophilus granarius (Coleoptera: Curculionidae)Rudy PLARREEur. J. Entomol. 107 (1): 1-11, 2010 | DOI: 10.14411/eje.2010.001 It is generally accepted that stored grain insects are food opportunists and, when originally made the transition to man-made storage facilities, came from natural reservoirs like bird or rodent nests. This may not be true for Sitophilus granarius. Among all stored-product insects, the granary weevil S. granarius is the only species never recorded outside of storage facilities. Anatomical, physiological, and behavioural aspects of recent and hypothetical ancestral species in the genus Sitophilus are presented and discussed in terms of adaptation to the anthropogenic storage of grain. Full development inside the host kernel, endosymbioses with bacteria, and the reduction in flight activity to prevent water loss in a dry environment can be regarded as pre-adaptations for the evolution of a full synanthropic grain pest of cosmopolitan distribution. Faunistic, archaeological, and historical evidences of the pest's origin and spread in conjunction with early agriculture are reviewed to support a hypothesis of a co-evolutionary event with the dawn of Neolithic agriculture. |
A new genus and species of the tribe Orthotylini (Heteroptera: Miridae: Orthotylinae) from Central AsiaAlexander A. KNYSHOV, Fedor V. KONSTANTINOVEur. J. Entomol. 109 (1): 117-128, 2012 | DOI: 10.14411/eje.2012.015 A new genus and new species, Angulonotus grisescens, is described from Kazakhstan and Uzbekistan and its taxonomic placement within the tribe Orthotylini is discussed. Illustrations of male and female genitalia, micrographs of selected characters, photographs of dorsal habitus, hosts and distributional records of this new taxon are provided. Comparisons are made with species of the genus Hyoidea Reuter, 1876. |
Comparison of the severity of selection among beech leaves prior to egg-laying between a leaf-mining and two gall-inducing insectsJean BÉGUINOTEur. J. Entomol. 108 (1): 71-78, 2011 | DOI: 10.14411/eje.2011.009 |
BOOK REVIEW: Oosterbroek P.: The European Families of the Diptera. Identification, diagnosis, biology.M. CHVÁLAEur. J. Entomol. 104 (3): 618, 2007 | DOI: 10.14411/eje.2007.076 KNNV Publishing, Utrecht, 2006, 205 pp., (www.knnvpublishing.nl), ISBN 90-5011-245-5 / 978-90-5011-245-1. Price EUR 59.95. |
Life cycle and growth pattern of the endangered myrmecophilous Microdon myrmicae (Diptera: Syrphidae)Magdalena WITEK, Sara CANTERINO, Emilio BALLETTO, Simona BONELLIEur. J. Entomol. 109 (3): 457-461, 2012 In Europe there are only a few species of the syrphid fly Microdon, which live in the nests of various genera of ants. For most of these rare flies, details of their biology, larval behaviour and relationships with their hosts are still not yet well known. In this paper we present data on the life cycle, feeding behaviour and growth pattern of Microdon myrmicae, a social parasite of Myrmica ants and compare it with two species of Maculinea butterflies similarly parasitizing Myrmica ant colonies. M. myrmicae has three larval instars and overwinters as a third instar. Eggs and 1st instar larvae are ignored by ants, which indicate that they are "chemically insignificant". 2nd and 3rd instar larvae feed on small ant brood. M.myrmicae larvae grow rapidly from May to July and later in the year the host colony only serves as shelter for overwintering. Like Maculinea alcon, larvae of M. myrmicae are numerous in Myrmica nests and more numerous than those of Maculinea teleius. Since the larvae of Microdon feed on an abundance of young ant brood, they experience low level of scramble competition and although many may develop in an ant's nest they have probably little effect on host colony fitness. |
The impact of male-killing bacteria on the evolution of aphidophagous coccinellidsMichael E.N. MAJERUSEur. J. Entomol. 103 (1): 1-7, 2006 | DOI: 10.14411/eje.2006.001 Many aphidophagous coccinellids harbour male-killing bacteria. These maternally inherited bacteria kill males early in embryogenesis, female offspring of infected mothers gaining a large resource advantage from the consumption of their dead brothers. In this paper, the diversity of male-killing bacteria and their coccinellid hosts will be briefly reviewed. Thereafter, the impact that invasion by male-killers has on coccinellid hosts will be addressed in two ways. First, the selective effects due to the loss of male progeny, and the intra-genomic conflict resulting from the cytoplasmic inheritance of the bacteria will be considered. Reductions in mitochondrial diversity, effects on clutch sizes and the evolution of male-killer suppresser systems will be discussed. Second, the impact of female biased population sex ratios on the evolution of reproductive strategies and the primary sex ratio will be investigated. Preliminary results suggesting changes in male investment per copulation, reductions in female testing behaviour of males, and male biases in the progenic sex ratios of some uninfected male lines will be presented. Avenues for future work will be outlined. |
BOOK REVIEW: Miller J.C., Janzen D.H. & Hallwachs W.: 100 Butterflies and moths: PoRtraits from the tropical forests of Costa Rica.Z. FRICEur. J. Entomol. 105 (4): 642, 2008 The Belknap Press of Harvard University Press, Cambridge, 2007, 256 pp., ISBN 978-0-674-02334-5. |
Crustacean red pigment-concentrating hormone Panbo-RPCH affects lipid mobilization and walking activity in a flightless bug Pyrrhocoris apterus (Heteroptera) similarly to its own AKH-peptidesRadomír SOCHA, Dalibor KODRÍK, Rostislav ZEMEKEur. J. Entomol. 104 (4): 685-691, 2007 | DOI: 10.14411/eje.2007.086 In the present study we tested whether the walking activity of macropterous females of the flightless wing-polymorphic bug Pyrrhocoris apterus (L.) can be stimulated by its native adipokinetic hormone Peram-CAH-II and the crustacean red pigment-concentrating hormone (Panbo-RPCH), and the effectiveness of the latter hormone in a lipid mobilization assay. Two different doses (10 or 40 pmol) of Peram-CAH-II or Panbo-RCPH were injected into 10-day-old macropterous females of P. apterus to evaluate their effects on the walking activity of treated females. The results obtained showed a significant stimulation of walking activity only with the lower dose (10 pmol) of either hormone Peram-CAH-II or Panbo-RPCH. On the contrary, the walking activity of the same-aged females of macropterous morph treated with the higher dose (40 pmol) of these hormones was decreased. The energy substrates mobilized in Panbo-RPCH-treated macropterous females were lipids. The question of whether the stimulation of locomotion by Panbo-RPCH is limited only to P. apterus or if it might also represent an important function of this hormone in other insects or even in crustaceans is discussed. |
Phylogenetic revision of the New Zealand genus Dasytricheta, with a discussion of its systematic position within the subfamily Aleocharinae (Coleoptera: Staphylinidae)Grzegorz PA¦NIKEur. J. Entomol. 104 (4): 815-826, 2007 | DOI: 10.14411/eje.2007.102 The genus Dasytricheta Bernhauer, 1943 is redefined. The genus Pyromecroma Cameron, 1945 is considered a new synonym of Dasytricheta. Eleven valid species are recognised in the genus: Dasytricheta spectabilis Bernhauer, 1943 (the type species of Dasytricheta), D. funesta (Broun, 1912) comb. n. (the type species of Pyromecroma, originally described in Myrmecopora Saulcy, 1864), and nine species described as new: Dasytricheta haastiana sp. n., D. hookeriana sp. n., D. intermedia sp. n., D. kapuniana sp. n., D. mahitahiana sp. n., D. periana sp. n., D. shotoveriana sp. n., D. testacea sp. n. and D. waihoana sp. n. The taxa are diagnosed, keyed and illustrated. The phylogeny of Dasytricheta is analysed using cladistic methods. The systematic position of Dasytricheta within the Aleocharinae is discussed. |
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-ROCHOWEur. 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. |
Life table parameters of the aphid predators Coccinella septempunctata, Ceratomegilla undecimnotata and Propylea quatuordecimpunctata (Coleoptera: Coccinellidae)Dimitrios C. KONTODIMAS, Panagiotis G. MILONAS, George J. STATHAS, Nickolaos E. PAPANIKOLAOU, Anna SKOURTI, Yiannis G. MATSINOSEur. J. Entomol. 105 (3): 427-430, 2008 | DOI: 10.14411/eje.2008.054 The life tables of the aphid predators Coccinella septempunctata L., Ceratomegilla undecimnotata (Schneider) and Propylea quatuordecimpunctata (L.) (Coleoptera: Coccinellidae), fed on Aphis fabae Scopoli (Hemiptera: Aphididae), were constructed at constant conditions (25 ± 1°C, 65 ± 2% RH; 16L : 8D). The average total fecundities of C. septempunctata, C. undecimnotata and P. quatuordecimpunctata were 1996.8, 1160.5, and 724.6 eggs / female, and the average longevities were 94.9, 88.3, and 68.9 days, respectively. The net reproductive rates (Ro) were 1004.1, 544.3, and 375.1 females/female, and the intrinsic rates of increase (rm) 0.118, 0.142 and 0.166 females/female/day, respectively. |
Rediscovery, redescription and reclassification of Beludzhia phylloteliptera (Diptera: Sarcophagidae: Miltogramminae)Krzysztof SZPILA, Thomas PAPEEur. J. Entomol. 104 (1): 119-137, 2007 | DOI: 10.14411/eje.2007.018 The species Beludzhia phylloteliptera Rohdendorf is redescribed from adult males and females as well as all larval instars collected in the United Arab Emirates. The morphology of the first instar larva is strikingly similar to that of Dolichotachina marginella (Wiedemann) and Phylloteles pictipennis Loew, all of which are here documented for the first time. These three generic representatives share several character states, which are probably plesiomorphic relative to the condition observed in other miltogrammine larvae, but the uniquely shaped, slender mouthhook, a cushion- or pad-like lobe behind the maxillary palpus (cheek organ), the antero-ventral segmental prolegs of the first instar larva, and the integumental warts of the third instar larvae, are shared character states not known from any other species of Sarcophagidae. Beludzhia Rohdendorf is therefore placed with Dolichotachina Villeneuve and Phylloteles Loew in the tribe Phyllotelini. |
The potential of carabid beetles (Coleoptera) to reduce slug damage to oilseed rape in the laboratoryFrank OBERHOLZER, Natalie ESCHER, Thomas FRANKEur. J. Entomol. 100 (1): 81-85, 2003 | DOI: 10.14411/eje.2003.016 Slugs are important pests of many agricultural crops, especially oilseed rape. The carabid beetles Pterostichus melanarius Illiger and Poecilus cupreus L. are among the most abundant large carabid beetles of European arable land and were therefore explored as potential slug antagonists. Damage to oilseed rape caused by the slugs Deroceras reticulatum Müller and D. laeve Müller in the presence or absence of P. melanarius and P. cupreus was observed in the laboratory. Whereas P. cupreus failed to reduce damage to oilseed rape by D. reticulatum, P. melanarius significantly reduced slug damage. However, P. melanarius was unable to protect oilseed rape from damage by D. laeve. This can be explained by the fact that D. laeve caused damage to oilseed rape below ground, where P. melanarius did not encounter the slugs. According to our laboratory experiments P. melanarius has the potential to reduce slug damage to oilseed rape by D. reticulatum. |
Origin of Jordanian honeybees Apis mellifera (Hymenoptera: Apidae) using amplified mitochondrial DNAShahera ZAITOUN, Dhia S. HASSAWI, Wesam SHAHROUREur. J. Entomol. 105 (1): 41-44, 2008 | DOI: 10.14411/eje.2008.005 The honeybee (Apis mellifera L.) has a large number of geographic subspecies distributed across Europe, Africa and Asia, many of which have been described. This identification is important for bee breeding and preserving honeybee biodiversity. To investigate the origin of Jordanian honeybees, 32 samples collected from different locations in Jordan were analyzed using four different enzyme systems: Bg/II site in cytochrome oxidase b (Cytb), EcoRI site in large ribosomal (lsRNA) subunit, XbaI site in cytochrome c oxidase I (COI) subunit and HinCII site in cytochrome c oxidase I (COI) subunit. The first three enzymes were found to be polymorphic. The DNA banding pattern analyses revealed that Jordanian honeybees belong to the East Mediterranean and Middle Eastern mitochondrial lineages. |
Male territorial behaviour of the endemic large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis (Hymenoptera: Apidae), on the oceanic Ogasawara IslandsShinji SUGIURAEur. J. Entomol. 105 (1): 153-157, 2008 | DOI: 10.14411/eje.2008.021 The endemic large carpenter bee, Xylocopa (Koptortosoma) ogasawarensis Matsumura (Hymenoptera: Apidae), on the oceanic Ogasawara (Bonin) Islands, located in the northwestern Pacific Ocean, approximately 1000 km south of the Japanese mainland, is a generalist flower visitor. Although the flower-visiting behaviour of X. ogasawarensis females has been frequently recorded, the behaviour of the males in this species has rarely been studied. I observed the territorial behaviour of males on flowers of the native plant species Scaevola sericea Vahl (Campanulales: Goodeniaceae) in a coastal area of Hahajima in early July 2007. Each male chose a particular inflorescence, hovered near it (mean distance, 239 mm from the inflorescence) and patrolled around it for several minutes (mean time, 331 s). Therefore, X. ogasawarensis males exhibit resource-based (i.e., flowers) territoriality. Males frequently attacked other males when defending their territories. However, males did not defend their territories against flower visitors of other species (i.e., introduced honeybees). Therefore, male territorial behaviour in X. ogasawarensis may be related to intrasexual competition for sites visited by females. This is the first report describing the male territorial behaviour of X. ogasawarensis. |
Ejaculate size varies with remating interval in the grasshopper Chorthippus parallelus erythropus (Caelifera: Acrididae)Klaus REINHARDTEur. J. Entomol. 104 (4): 725-729, 2007 | DOI: 10.14411/eje.2007.092 The number of sperm a male ejaculates is influenced, among other factors, by male age, time since last copulation and possibly a combination of both. Males of Chorthippus parallelus erythropus were subjected to three successive matings in which males had a remating interval of either one or three days. The first ejaculate was very variable. It contained a mean of 433,000 sperm. If there was a one-day interval between matings, the second and third ejaculate comprised 16-19% of the number of sperm in the first ejaculate, respectively. Its sister taxon, the subspecies Chorthippus p. parallelus showed a similar second ejaculate size but the third ejaculate further declined to 8-10% compared to the first. If there were three days between matings, second and third ejaculates comprised 148.3% and 63.1% of the number of sperm in the first ejaculate in Chorthippus p. erythropus. This was markedly different to two individuals of Chorthippus p. parallelus where second and third ejaculates comprised 597% and 416% of the first. It is speculated that this indicates an overall higher sperm production because testis size was also larger in Chorthippus p. parallelus than Chorthippus p. erythropus. The results also show that theoretical models on sperm allocation may underestimate the rate and age-dependency of sperm replenishment. |
Cladistic analysis of Sericania (Coleoptera: Scarabaeidae: Sericini) - implications for the evolution of the xerophilous fauna of the HimalayaDirk AHRENSEur. J. Entomol. 104 (3): 517-530, 2007 | DOI: 10.14411/eje.2007.072 A cladistic analysis of the species of Sericania Motschulsky, 1860, was executed using fifty-six morphological characters of adults. The monophyly of the genus is supported by the phylogenetic trees generated. Among the three major lineages indicated by the strict consensus tree the East Asian Sericania fuscolineata lineage represents the genus Sericania as defined "originally" and adopted by subsequent authors. The second, the clade Sericania nepalensis group + Sericania sp. 2, is a sister group to the S. fuscolineata clade. Both constitute a sister group to the third major lineage, the Sericania kashmirensis clade, which is endemic in the drier North-West Himalaya where it is the most diverse monophyletic group of Sericini. Provided that the stem species of the S. kashmirensis clade was xerophilous, the origin of this clade can not predate the early Miocene. Based on paleoclimatical and geological data, two competing hypotheses are proposed to explain the evolution of the xerophilous Sericania lineage: (a) a basal splitting within Sericania occurred because of the altitudinal and climatic barrier posed by the Himalaya, which separated the xerophilous lineage in the north (Tibet) from the hygrophilous lineage in the south-east (S slope of Himalaya/ Tibet), or (b) it was a consequence of the increase in the climatic east-west contrast along the southern slope of the Himalaya, which strengthened with the onset of monsoons 8 Ma ago. |
Phyllotreta striolata (Coleoptera: Chrysomelidae): Arginine kinase cloning and RNAi-based pest controlYiying ZHAO, Guang YANG, Gefu WANG-PRUSKI, Minsheng YOUEur. J. Entomol. 105 (5): 815-822, 2008 | DOI: 10.14411/eje.2008.108 Insect pests cause billions of dollars in crop losses and there is the ever-present threat of insecticide resistance, pesticide pollution of food and environmental damage. New ways of controlling insect pests are urgently needed. Arginine kinase (AK) is a phosphotransferase, which plays a critical role in cellular energy metabolism in invertebrates. It only presents in invertebrates and may be a suitable chemotherapeutic target in the control of pests. In this study, we cloned and characterized the full-length AK gene from Phyllotreta striolata, one of the most destructive beetle pests worldwide. Furthermore, we constructed a dsRNA targeting AK and used RNAi to control the beetle. The feeding bioassays indicated that minute quantities of dsRNA greatly impaired the beetle's development. Ingestion of dsRNA not only significantly retarded the development and increased the mortality of adults, it also greatly reduced fecundity and fertility, suggesting that RNAi targeting AK is a potential and attractive tool for controlling insect pests. |
Experimental evidence for competitive exclusion of Myzus persicae nicotianae by Myzus persicae s.s. (Hemiptera: Aphididae) on sweet pepper, Capsicum annuum (Solanaceae)Daniel H. TAPIA, Alejandra J. TRONCOSO, Renzo R. VARGAS, Ruby OLIVARES-DONOSO, Hermann M. NIEMEYEREur. J. Entomol. 105 (4): 643-648, 2008 The importance of interspecific competition as a force promoting specialization in phytophagous insects has been long debated. Myzus persicae sensu stricto (Hemiptera: Aphididae) is one of the most polyphagous aphids. Its subspecies, M. persicae nicotianae, is found mainly on tobacco, although it can survive and reproduce on a relatively wide range of plant species in the laboratory. Since life history traits of these taxa make competitive interactions likely, we hypothesize that asymmetrical competition occurs between M. p. nicotianae and M. persicae s.s., and accounts for the exclusion of the former when they share a common resource. This hypothesis was tested in laboratory experiments, which examined the population growth of colonies of both taxa coexisting on sweet pepper. A replacement series experiment was set up with both aphid taxa on sweet pepper plants, and the rates of population growth (RPG) evaluated at 5 day intervals for 25 days. M. p. nicotianae showed a significantly lower RPG when interacting with M. persicae s.s. than when in monotypic colonies, while M. persicae s.s. RPG was unaffected by competition. The relative population growth from the second census onwards of M. persicae s.s. was consistently higher than that of M. p. nicotianae. Finally, the RPG of M. p. nicotianae was significantly reduced when the plant was infested with M. persicae s.s. The results suggest that the absence of M. p. nicotianae from sweet pepper in the field in Chile can be partly explained by competitive exclusion by M. persicae s.s. |
Polygraphus grandiclava (Coleoptera: Curculionidae) collected from pine and cherry trees: A phylogenetic analysisDimitrios AVTZIS, Milo¹ KNÍ®EK, Klaus HELLRIGL, Christian STAUFFEREur. J. Entomol. 105 (4): 789-792, 2008
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