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A comprehensive study of the changes in ecdysteroid levels during the feeding phase of fifth instar larvae of the silkworm, Bombyx mori (Lepidoptera: Bombycidae)Bela KESHAN, Bembem THOUNAOJAM, Sanathoibi D. KHEur. J. Entomol. 112 (4): 632-641, 2015 | DOI: 10.14411/eje.2015.088 The present study describes changes in haemolymph ecdysteroid levels during the feeding phase of fifth instar larvae of Bombyx mori. A small and sharp peak in ecdysteroid level was recorded on day 4 when larvae had already reached the critical weight (2.76 ± 0.11 g) for metamorphosis. Food deprivation of larvae from day 4 resulted in an increase in the ecdysteroid level. Injection of insulin in both 1 day (before reaching critical weight) and 4 day (after reaching critical weight) old fed larvae resulted in an increase in the ecdysteroid level. However, when deprived of food only the haemolymph ecdysteroid levels of 4 day old larvae respond to an injection of insulin. The hormone level was also increased by treating 1day old larvae with a juvenile hormone analogue, but again, like insulin, only the fed larvae were affected by this treatment. Neck- and thorax-ligated 4 day old larvae had decreased ecdysteroid levels compared to both fed and food deprived larvae. However, a significant increase in ecdysteroid level was recorded in both neck- and thorax-ligated larvae injected with insulin. The injection of 20-hydroxyecdysone into 4 day old larvae resulted in an increase in the level of this substance in the haemolymph of fed and food deprived larvae, but the level was significantly higher in neck- and thorax-ligated larvae. The data, thus, indicates that ecdysteroid levels vary both in relation to the critical weight of the larvae and its nutritional status, and insulin might also play an important role in regulating the level of ecdysteroid. |
Wing morphology is linked to stable isotope composition of nitrogen and carbon in ground beetles (Coleoptera: Carabidae)Marcin ZALEWSKI, Dorota DUDEK-GODEAU, Alexei V. TIUNOV, Jean-François GODEAU, Yutaka OKUZAKI, Hiroshi IKEDA, Pawe³ SIENKIEWICZ, Werner ULRICHEur. J. Entomol. 112 (4): 810-817, 2015 | DOI: 10.14411/eje.2015.072 As movement is expensive in terms of energy required, mobile animals might have to utilize more energy rich resources than less mobile animals. As mobile animals are possibly more effective foragers we hypothesize a positive correlation between mobility and trophic niche width. We address this link using information on the trophic level of 35 winged, wingless and wing dimorphic species of ground beetles studied on 18 lake islands and at two mainland sites in northern Poland. Trophic analyses using stable isotope values (δ15 N, δ13C) revealed that winged individuals of wing dimorphic species are characterized by broader isotopic niches than wingless individuals. Macropterous species are characterized by depleted δ13C values, which can be interpreted in terms of lipid-rich prey selection. Wing dimorphic species are characterized by higher trophic levels, as inferred from δ15 N values, than winged species. Numbers of islands colonized by particular species were not correlated with δ15 N values, δ13C values or isotopic niche width. Our results point to a relationship between diet and wing morphology in ground beetles. |
Tettigoniidae (Orthoptera) ovipositing in old galls of Dryocosmus kuriphilus (Hymenoptera: Cynipidae)NoteGiuliano CERASA, Bruno MASSAEur. J. Entomol. 113: 397-402, 2016 | DOI: 10.14411/eje.2016.051 This paper presents biological notes on two species of Orthoptera: Tettigoniidae that emerged from old spongy-woody galls of Dryocosmus kuriphilus Yasumatsu, 1951 collected in Sicily (Italy) in April 2015: Leptophyes sicula Kleukers, Odé et Fontana, 2010 (Phaneropterinae) and Cyrtaspis scutata (Charpentier, 1825) (Meconematinae). Between the end of April and the first few days of May a total of 30 neanids emerged from the galls, were reared and their life-cycle recorded. While L. sicula laid eggs in groups, C. scutata laid single eggs inside the galls; both species in a few years have adapted to exploiting this new shelter for egg laying. No interaction with the gall inducing insect was noted. |
The mitochondrial genome of the Mediterranean flour moth, Ephestia kuehniella (Lepidoptera: Pyralidae), and identification of invading mitochondrial sequences (numts) in the W chromosomeOriginal articleKatrin LÄMMERMANN, Heiko VOGEL, Walther TRAUTEur. J. Entomol. 113: 482-488, 2016 | DOI: 10.14411/eje.2016.063 The Mediterranean flour moth, Ephestia kuehniella is a widespread pest of stored products and a classical object in experimental biology. In the present study, we determined its complete mitochondrial genome sequence. The genome is circular, consists of 15,327 bp and comprises 13 protein-coding, 2 rRNA- and 22 tRNA-coding genes in an order typical for the Ditrysia clade of the order Lepidoptera. A phylogenetic study of the Lepidoptera based on complete mitochondrial genomes places E. kuehniella correctly in the family Pyralidae and supports major lepidopteran taxa as phylogenetic clades. The W chromosome of E. kuehniella is an exceptionally rich reservoir of originally mitochondrial sequences (numts). Around 0.7% of the W DNA was found to be of mitochondrial origin, 83% of the mitogenome sequence was represented between 1-11 × in the W chromosome. Phylogenetic analysis further revealed that these numts are an evolutionary recent acquisition of the W chromosome. |
Occurrence of Harmonia axyridis (Coleoptera: Coccinellidae) in field cropsAxel VANDEREYCKEN, Yves BROSTAUX, Emilie JOIE, Eric HAUBRUGE, François J. VERHEGGENEur. J. Entomol. 110 (2): 285-292, 2013 | DOI: 10.14411/eje.2013.042 The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of this exotic species and its seasonal abundance in various field crops. The abundance of adults, larvae and pupae of H. axyridis was evaluated over a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. From May to September, 48 1-m2 quadrats were visually inspected in each of the fields sampled on several farms every seven days. H. axyridis colonized and reproduced in all of the four crops studied, with the largest numbers recorded in corn and broad bean crops. Larvae and adults of H. axyridis were recorded mainly in corn and to a much less extent in wheat and potato crops. From 2009 to 2011, the mean weekly abundance of H. ayxridis remained constant except in corn crops, where the recorded densities of all the immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis are well described by a symmetric logistic function (S-shape) of cumulative population size. H. axyridis was not always recorded where aphids were abundant, e.g. aphids were abundant on wheat where no H. axyridis were recorded. H. axyridis start reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of the same and other species of ladybird and other aphidophagous species. H. axyridis is often considered to be bivoltine but it only completes one generation per year in field crops. The second generation generally develops late in the season in other habitats. |
Nutrient-specific food selection buffers the effect of nutritional imbalance in the mealworm beetle, Tenebrio molitor (Coleoptera: Tenebrionidae)Myung Suk RHO, Kwang Pum LEEEur. J. Entomol. 112 (2): 251-258, 2015 | DOI: 10.14411/eje.2015.030 Ingesting nutritionally imbalanced food can cause a significant reduction in fitness in insects. Insects can avoid the negative consequences of nutritional imbalances by selectively foraging for nutritionally complementary foods. We investigated the ability of the omnivorous beetle, Tenebrio molitor (Coleoptera: Tenebrionidae), to redress nutritional imbalances by selecting complementary foods. Beetles were fed one of three synthetic diets that varied in their protein: carbohydrate balance (p0:c42, p21:c21 or p42:c0) for 16 days and then allowed to select between two nutritionally imbalanced but complementary diets (p0:c42 vs. p42:c0) for 18 days. During the initial period, beetle survival was high on all three experimental diets, but their body composition was considerably skewed as a result of eating nutritionally imbalanced diets. Over the first 6 days of food choice (days 16-22), beetles previously fed a protein-rich, carbohydrate-deficient diet (p42:c0) preferred carbohydrate to protein, whereas those previously fed a carbohydrate-rich, protein-deficient diet (p0:c42) strongly preferred the protein-rich diet. When the food choice period continued for longer than 6 days, the selection of diets by previously carbohydrate-deprived beetles (p42:c0) was similar to that of the control beetles previously fed an optimal food (p21:c21). However, beetles that were previously fed on the protein-deficient diet (p0:c42) selected protein and carbohydrate equally throughout the remaining period of food choice and the cumulative protein-carbohydrate intake of these protein-deprived beetles was similar to that of those fed the optimal diet (p21:c21). At the end of the experiment, the body composition of all beetles was similar, indicating that the effects of nutritional imbalance on body composition were buffered by the subsequent selection of complementary foods. Our results demonstrate that T. molitor beetles are capable of redressing nutritional imbalances and indicate that the way in which the nutritional balance of beetles is restored depends on the nutrient that is initially deficient in their food. |
Population dynamics, seasonality and aphid prey of Cheilomenes sexmaculata (Coleoptera: Coccinellidae) in an urban park in central JapanOriginal articleYasuko KAWAKAMI, Kazuo YAMAZAKI, Kazunori OHASHIEur. J. Entomol. 113: 192-199, 2016 | DOI: 10.14411/eje.2016.023 The ladybird beetle, Cheilomenes sexmaculata (Fabricius), has been extending its distribution in and around urban areas at higher latitudes in Japan over the past 100 years. Between 2003 and 2011, we investigated the seasonal occurrence, aphid prey and population dynamics of this species in an urban park in Osaka City, central Japan. We found that C. sexmaculata completes three generations a year in Osaka. Overwintered adults emerge in March or April and produce two (or rarely one) generations by summer. Second-generation adults aestivate and subsequently produce another generation in autumn. This species feeds on five species of aphids that infest planted shrubs and alien weeds throughout the vegetative season. We analyzed the association between accumulated temperature and when overwintered adults first emerged. In addition, we determined the association between their time of emergence, peak abundance and last occurrence, and meteorological conditions. There was no association between the sum of effective temperatures and termination of adult overwintering. There was, however, an association between first occurrence and peak abundance, and climatic conditions, such as warm temperatures or low humidity. This species maintained a stable population in an urban park by becoming quiescent when climatic conditions were unfavourable or prey was scarce. We discussed these findings in relation to urban environmental factors, such as climate, food conditions and vegetation. |
Life cycle, seasonal and interannual polymorphism in a monoecious aphid Cinara mordvilkoi (Hemiptera: Aphidoidea: Lachnidae)Roma DURAKEur. J. Entomol. 111 (3): 357-362, 2014 | DOI: 10.14411/eje.2014.051 This paper presents the first description of the life cycle of Cinara mordvilkoi and alary dimorphism of its males. There are 3 phases in its life cycle and during the course of a year 10 generations of parthenogenetic females are produced. The durations of development of subsequent generations over three years were recorded. C. mordvilkoi was observed to change its feeding position on its host from leaves to roots throughout the year. In the third year of this study both winged and wingless males were recorded. The fundatrix, oviparous female and the apterous and winged males are described. |
Influence of natal host on parasitism by Spalangia cameroni (Hymenoptera: Pteromalidae)Original articleFrancisco BEITIA, Erik VALENCIA, Bernat PERIS, Luis DE PEDRO, Josep D. ASÍS, José TORMOSEur. J. Entomol. 113: 99-103, 2016 | DOI: 10.14411/eje.2016.012 Spalangia cameroni Perkins (Hymenoptera: Pteromalidae) is sold commercially as a biocontrol agent of filth flies, including the house fly, Musca domestica L. (Diptera: Muscidae). For this reason, S. cameroni is mass-reared for inundative releases to control harmful flies. However, the mass-rearing protocols include very little information on the influence of natal host on subsequent host selection by parasitoids with more than one potential host as in the genus Spalangia. Here, we report on the use of S. cameroni against M. domestica. The S. cameroni were reared using Ceratitis capitata Wiedemann (Diptera: Tephritidae) (natal host) pupae for several generations. Freeze-killed fly pupae were used in assays to determine the fecundity, number of adult progeny and sex-ratio of this parasitoid. Realized fecundity and number of adult progeny were greater when provided with house fly pupae than Mediterranean fruit fly pupae. Thus S. cameroni parasitized more house fly pupae than C. capitata pupae, even though the parasitoid was reared on Mediterranean fruit fly for many generations. These results indicate that S. cameroni reared on C. capitata can be successfully used in inundative releases against both fruit flies (agriculture) and house flies (livestock farming). |
Reproductive status of Tribolium castaneum (Coleoptera: Tenebrionidae) affects its response to infection by Steinernema feltiae (Rhabditida: Steinernematidae)Original articlePaulina KRAMARZ, Dariusz MA£EK, Maria GAWE£, Szymon M. DROBNIAK, Joanna HOMAEur. J. Entomol. 113: 309-314, 2016 | DOI: 10.14411/eje.2016.039 Gender-specific reproductive roles are important factors determining sexual dimorphism. Here, we investigate the effects of sex-based differences and reproductive status on the defence of Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae) against infection by Steinernema feltiae (Filipjev, 1934) (Rhabditida: Steinernematidae). Female and male beetles, either virgin or post-copulation, were exposed individually to nematodes. Individuals were then sampled every 12 h, dissected, and checked for the presence of nematodes; we also measured their phenoloxidase (PO) activity. Reproductive status affected resistance to nematodes and PO activity as infected virgin individuals had a higher PO activity and lower mortality than reproducing individuals, with no differences between sexes. Mortality also increased with time, while PO activity did not change. Parasite load was related to reproductive status and sex, with reproducing females with the highest parasite loads in all treatments, and virgin males with more nematodes than sexually active males. Our results indicate that the costs of reproduction impair the immunological system of T. castaneum similarly in both sexes. It is possible, however, that other components of the immunological system that we did not measure, such as lysozyme activity, are impaired by infection with S. feltiae in a sex-specific way. |
Age dependent mate choice influences reproductive and progeny attributes in aphidophagous ladybird beetles (Coleoptera: Coccinellidae)Mahadev BISTA, OMKAREur. J. Entomol. 112 (4): 648-657, 2015 | DOI: 10.14411/eje.2015.082 Despite the many studies on age based mate choice in insects, the question of how age influences mate choice in predaceous ladybird beetles is still unexplored. The present study evaluates age based mate choice in two sympatric aphidophagous ladybirds, Coccinella septempunctata L. and Coccinella transversalis Fab., in terms of mating behaviour (latent period, number of bouts, bout interval and duration of wriggling movements and mating), fecundity, egg viability and the development and survival of their progeny. Results revealed that middle aged (30-40 days) mates were preferred by young (10-15 days post-eclosion), middle aged (30-40 days) and old (45-55 days) individuals of both sexes. Mating behaviour and egg viability differed significantly with male age whereas fecundity, offspring development and survival differed significantly with female age. The shortest latent periods and bout intervals, highest numbers of bouts, longest durations of wriggling movements and mating, and maximum egg viability were recorded for middle aged males whereas fecundity, percentage pupation and adult emergence of offspring were highest and durations of immature development were shortest for middle aged females. Thus, the present study indicates that middle aged individuals of C. septempunctata and C. transversalis are most preferred as mates as they have the highest reproductive output and produce the fittest offspring. |
Identification of microsatellite markers for a worldwide distributed, highly invasive ant species Tapinoma melanocephalum (Hymenoptera: Formicidae)NoteJan ZIMA Jr., Ophélie LEBRASSEUR, Michaela BOROVANSKÁ, Milan JANDAEur. J. Entomol. 113: 409-414, 2016 | DOI: 10.14411/eje.2016.053 Tapinoma melanocephalum is a worldwide distributed, highly invasive ant species. It lives in close association with human societies and its distribution is human-mediated in large measure. The geographical origin of this ant species is unknown, but its introduction in areas previously devoided of its presence can represent a threat to the native biota, act as an agricultural pest or as a pathogen vector. To investigate the genetic structure and phylogeography of this species we identified 12 new polymorphic microsatellite markers, and in addition, we tested and selected 12 ant-universal microsatellites polymorphic in T. melanocephalum. We genotyped 30 individuals from several islands of Micronesia and Papua-New Guinea. All 24 loci exhibited strong homozygosity excess (45-100%, mean = 86%), while the number of alleles per locus reached usual values (2-18, mean = 6.5), resulting in levels of expected heterozygosity much higher than observed. Based on several robust tests, we were able to exclude artefacts such as null alleles and allelic dropout as a possible cause of the observed pattern. Homozygosity excess might be a consequence of founder effect, bottleneck and/or inbreeding. As our sample population was composed of individuals from several distinct localities, the Wahlund effect might have contributed to the increased homozygosity as well. Despite the provisionally observed deviation from the Hardy-Weinberg equilibrium, the newly developed microsatellites will provide an effective tool for future genetic investigations of population structure as well as for the phylogeographic study of T. melanocephalum. |
Comparison of the exotic and native ant communities (Hymenoptera: Formicidae) in urban green areas at inland, coastal and insular sites in SpainJoaquín REYES-LÓPEZ, Soledad CARPINTEROEur. J. Entomol. 111 (3): 421-428, 2014 | DOI: 10.14411/eje.2014.044 Currently the introduction and spread of invasive species is an issue of great concern. To effectively manage this problem it is essential to know what constitute invasion hotspots. In this respect, the role of urban green areas in the conservation of biodiversity is a controversial matter. These areas may either favour colonization by alien species or shelter species of high conservation value. We evaluated the influence of location (island, coastal or inland) on the exotic and native ant fauna recorded in 27 urban green areas in Spain. A forward-stepwise discriminant analysis revealed differences between these locations in terms of the composition of the fauna, with exotic species identified as being the most important discriminating variable. There is a gradient: inland-coastal-island, along which there is significant increase in importance in terms of species richness and abundance of particular exotic species and decrease in the dominance of both common and rare native species. Areas located on the Island were more susceptible to invasion by alien ants. Coastal areas were also more susceptible to invasion than inland areas. These results possibly reflect the greater probability of an invasive species reaching these locations and the milder weather conditions at these sites, which would favour their establishment. |
Feeding of Scydmaenus rufus (Coleoptera: Staphylinidae: Scydmaeninae) on oribatid and uropodine mites: Prey preferences and hunting behaviourPawe³ JA£OSZYÑSKI, Ziemowit OLSZANOWSKIEur. J. Entomol. 112 (1): 151-164, 2015 | DOI: 10.14411/eje.2015.023 Prey preferences and feeding-related behaviour of a Central European species of Scydmaeninae, Scydmaenus rufus, were studied under laboratory conditions. Results of prey choice experiments involving 22 identified species of mites belonging to 13 families of Oribatida and two families of Mesostigmata (Uropodina) demonstrated that this beetle feeds mostly on oribatid Scheloribatidae (60.38% of prey) and Oppiidae (29.75%) and only occasionally on uropodine Urodinychidae (4.42%) and oribatid Mycobatidae (3.39%); species belonging to Trematuridae (Uropodina), Ceratozetidae and Tectocepheidae (Oribatida) were consumed occasionally. The number of mites consumed per beetle per day was 1.42, and when Oppia nitens was the prey, the entire feeding process took 2.93-5.58 h. Observations revealed that mechanisms for overcoming the prey s defences depended on the body form of the mite. When attacking oribatids, with long and spiny legs, the beetles cut off one or two legs before killing the mite by inserting one mandible into its gnathosomal opening. Flattened and short-legged uropodines were killed in the same way but without cutting off their legs. More legs of the prey were removed during feeding, when the mite was already dead; in Oribatida additional damage included removal of genital plates, whereas the genital structures remained intact in Uropodina. Scydmaenus rufus was able to feed on potentially highly toxic Scheloribatidae, which raises questions about the efficiency of chemical defence in Oribatida. |
Immunomodulation in insects post-treatment with abiotic agents: A reviewEl-Sayed H. SHAURUBEur. J. Entomol. 109 (3): 303-316, 2012 The effects of different abiotic agents that may modulate the activity of an insect's immune system are reviewed. These agents include insecticides, chitin synthesis inhibitors, juvenile hormone analogues, inert particles, antibiotics, heavy metals, radiation and miscellaneous substances. The significance of studying immunomodulation in insects treated with abiotic agents in relation to both insect control and insect-borne parasitic diseases and the link between immunomodulation in insects post-treatment with both abiotic and biotic agents are discussed. |
Origin of the complex karyotype of the polyploid parthenogenetic grasshopper Saga pedo (Orthoptera: Tettigoniidae)Anne Marie DUTRILLAUX, Michèle LEMONNIER-DARCEMONT, Christian DARCEMONT, Vladimir KRPAÈ, Pierre FOUCHET, Bernard DUTRILLAUXEur. J. Entomol. 106 (4): 477-483, 2009 | DOI: 10.14411/eje.2009.060 Karyotypes of the polyploid parthenogenetic species Saga pedo from four localities in France and the Republic of Macedonia were constructed and compared. All these karyotypes consist of 70 chromosomes, which is more than twice that in other species of the genus. The chromosomes differ from each other, making the matching of homologues difficult. Karyotypes of French specimens are similar, except for differences in the heterochromatin. Compared to that of the Macedonian specimens those from French specimens differ by the shortening of a single chromosome. The difficulty experienced in identifying tetrads and even pairs of chromosomes indicates that either many chromosome rearrangements have occurred since the polyploidisation event(s) or that the addition of quite different genomes is the cause. On the other hand, that the karyotypes are similar indicates a common origin of both the Macedonian and French populations. Thus, most chromosome changes preceded the separation from their common ancestor. Both the DNA content and chromosome analyses suggest that the S. pedo karyotype is pentaploid and not tetraploid as previously proposed. This odd ploidy number rules out the hypothesis that it could only have originated by endoreduplication. It is more likely that it originated by the association of five copies of the 14,X haploid karyotype, which exists in the gametes of the closely related species, S. campbelli and S. rammei (male / female 2n = 27, X / 28, XX). Fertilization of a parthenogenetic 56, XXXX female by a 14, X spermatozoa could have resulted in the last increase in ploidy. |
Quantifying predation pressure along an urbanisation gradient in Denmark using artificial caterpillarsMarco FERRANTE, Alessandro LO CACCIATO, Gabor L. LÖVEIEur. J. Entomol. 111 (5): 649-654, 2014 | DOI: 10.14411/eje.2014.082 Urbanisation results in a marked modification of habitats and influences several ecological processes, some of which give rise to beneficial ecological services. Natural pest control, the effect of predators on prey is one of such services. We quantified changes in the incidence of predation with increasing levels of urbanisation using artificial caterpillars made of green plasticine. Potential predators can be identified by the "attack marks" they leave on these artificial caterpillars. We conducted this study from May to October 2010 around the city of Sorø (Zealand, Denmark), in forests along an urbanisation gradient (rural-suburban-urban). Artificial caterpillars were placed on the ground in order to obtain an estimate of the incidence of predation at ground level. Half (50%) of the 1398 caterpillars were "attacked" and 28.8% of the bites were those of chewing insects. We attributed the majority of these to carabids, the most common group of ground-active arthropods. Chewing insects exerted the greatest predation pressure in the original forest (52.1%), with lower values recorded in the suburban (10.1%) and urban (16.4%) forest fragments. Ants were responsible for only 4.7% of the attacks in forest, 11.3% in suburban and 16.4% in urban forest fragments. Mammals exerted the highest predation pressure in suburban habitats (22.2% vs. 4.9% in forest, and 8.1% in urban forest fragments). |
A revision of the cleptoparasitic bee genus Coelioxys (Hymenoptera: Megachilidae) from AustraliaOriginal articleLéo Correia da ROCHA-FILHOEur. J. Entomol. 113: 9-28, 2016 | DOI: 10.14411/eje.2016.002 The Australian species of the genus Coelioxys Latreille are revised. Six species are recognized: Coelioxys albolineata Cockerell, 1905; Coelioxys froggatti Cockerell, 1911; Coelioxys reginae Cockerell, 1905; Coelioxys weinlandi Schulz, 1904 and two new species: Coelioxys julia sp. n. and Coelioxys tasmaniana sp. n. Three names are synonymized: Coelioxys biroi Friese, 1909 syn. n. and Coelioxys albolineata darwiniensis Cockerell, 1929 syn. n. under Coelioxys albolineata, and Coelioxys victoriae Rayment, 1935 syn. n. under Coelioxys froggatti. Species descriptions and redescriptions, illustrations, distribution maps, floral records and a key to both sexes of all species are provided. |
Invasive ant Tapinoma melanocephalum (Hymenoptera: Formicidae): A rare guest or increasingly common indoor pest in Europe?Petr KLIME©, Jan OKROUHLÍKEur. J. Entomol. 112 (4): 705-712, 2015 | DOI: 10.14411/eje.2015.089 The ghost ant (GA), Tapinoma melanocephalum (Fabricius, 1793), is one of the most common invasive species of ants (Hymenoptera: Formicidae) in the world. While in its native tropical region it is both an ordinary indoor and outdoor pest, it occurs only indoors in the temperate zone, where increasingly more records of this species have been published since 1887. In this study, the current distribution of GA in Europe, including the new records published since Wetterer (2009), is reviewed. Furthermore, we report the first record of GA in the Czech Republic, where a large colony of GA was discovered in a block of flats in Èeské Budìjovice in 2014, and present a case study of its eradication. The revised distribution of GA shows that despite previous concerns about the threats posed by this new pest only three other European countries (including Czech Republic) reported the presence of this species after 2009. Although GA is currently documented as occurring in 18 European countries, which were invaded mainly after 1990, there is only a single (or dubious) record for ten of these countries. Abundance of workers was monitored in two flats in an infested building using traps baited with yolk-honey and GA were subsequently eradicated with imidacloprid (0.01% w/w). The pre-treatment revealed abundances that ranged up to 524 workers per trap (mean = 99, S.D. = 142, 80% of baits occupied). Despite the initial success of the treatment (no ants observed after 3 weeks), monitoring of the building a year later revealed it was still infested with GA and in a similar rate. We suggest alternative methods of eradicating GA in the temperate zone based on studies carried out in the tropics. Our study indicates the difficulty of eradicating the species from buildings when its colony is already established. Furthermore, it highlights the bias in the discovery-probability of GA as a household pest probably due to the species cryptic appearance and lack of attention to it outside of the scientific community. |
The effect of ambient temperature on larvae of Scatopsciara cunicularius (Diptera: Sciaridae) feeding on the thallose liverwort Marchantia polymorphaOriginal articleWeerachon SAWANGPROH, Johan EKROOS, Nils CRONBERGEur. J. Entomol. 113: 259-264, 2016 | DOI: 10.14411/eje.2016.030 Herbivory on liverworts is rarely reported. We studied the effects of feeding by larvae of the sciarid fly Scatopsciara cunicularius on the growth of the thalloid liverwort Marchantia polymorpha at two different constant temperatures, 12°C and 22°C. Larvae reared at the lower temperature fed slower and over a longer period of time, which resulted in more damage and a greater reduction in the growth of the liverwort than that caused by those reared at the higher temperature. The reduction in growth of the liverwort was positively density-dependent in terms of number of larvae at both temperatures. These results indicate that the larvae of S. cunicularius are likely to be an effective means of controlling M. polymorpha, which is a common weed in plant nurseries and greenhouse cultures. |
Potential pollinator of Vanda falcata (Orchidaceae): Theretra (Lepidoptera: Sphingidae) hawkmoths are visitors of long spurred orchidKenji SUETSUGU, Koji TANAKA, Yudai OKUYAMA, Tomohisa YUKAWAEur. J. Entomol. 112 (2): 393-397, 2015 | DOI: 10.14411/eje.2015.031 Vanda falcata is a species of orchid native to China, Korea and Japan. While it is arguably one of the most celebrated orchids in Japan there is no information on its pollinators. Although most species of the subtribe Aeridinae, to which V. falcata belongs, have a short spur, V. falcata has a long spur. The results of the current study provide strong evidence that V. falcata is pollinated by long-tongued hawkmoths (Theretra spp.), which indicates that the evolution of long spurs in V. falcata could be an adaptation to pollination by long-tongued moths. |
Cellular immune response of the Asian corn borer, Ostrinia furnacalis (Lepidoptera: Pyralidae), to infection by the entomopathogenic fungus, Beauveria bassianaOriginal articleDongxu SHEN, Miao LI, Yuan CHU, Minglin LANG, Chunju ANEur. J. Entomol. 113: 415-422, 2016 | DOI: 10.14411/eje.2016.054 The term cellular immune response refers to haemocyte-mediated responses, including phagocytosis, nodulation, and encapsulation. In the present study, we identified five types of circulating haemocytes in larvae of the haemolymph of the Asian corn borer, Ostrinia furnacalis (Guenée), including granulocytes, oenocytoids, plasmatocytes, prohaemocytes, and spherulocytes. The relative number of total free haemocytes per larva decreased significantly 0.5, 24, and 36 h after the injection of Beauveria bassiana conidia. Upon conidia challenge, both phagocytosis and nodulation were observed in the collected haemolymph from O. furnacalis larvae. In addition, plasma was found to be necessary for both phagocytosis and nodulation. Therefore, we here confirm that phagocytosis and nodulation are involved in O. funacalis larvae during their fight against infection by B. bassiana, and further, that the cellular immune response of O. furnacalis helps eliminate the invading organisms despite the fact that not all the fungal conidia are killed. |
Identification and abiotic stress response of a glutamine synthetase gene (AccGS) from the Asiatic honeybee, Apis cerana cerana (Hymenoptera: Apidae)Xiuling WANG, Yuzhen LI, Yan YAN, Baohua XU, Xingqi GUOEur. J. Entomol. 111 (1): 1-9, 2014 | DOI: 10.14411/eje.2014.001 Glutamine synthetase (GS) is an essential detoxification enzyme that plays an important role in stress responses; however, little information regarding the function of this enzyme in hymenopteran insects is available. In the present study, we isolated and characterized the gene encoding GS in the Asiatic honeybee, Apis cerana cerana. Multiple alignments and a phylogenetic analysis of GS sequences showed that AccGS belongs to the GSII superfamily and clusters with invertebrate GSs. Real-time quantitative PCR data demonstrated that AccGS is expressed at all developmental stages and in all tissues, with the highest expression observed in the sixth larval instar and in the brain. Moreover, AccGS expression is highly regulated by environmental stress, including xenobiotic, temperature, and ultraviolet light stresses. A disc diffusion assay showed that the recombinant AccGS protein confers resistance to mercuric chloride (HgCl2) stress in E. coli. This suggests that AccGS may play multiple roles in early development and in environmental stress responses. |
Do sexually dimorphic glands in the harvestman Gryne perlata (Arachnida: Opiliones) release contact pheromones during mating?Original articleJéssica M. DIAS, Rodrigo H. WILLEMARTEur. J. Entomol. 113: 184-191, 2016 | DOI: 10.14411/eje.2016.022 There are records of glands that produce sexual pheromones that are released into the environment or applied directly on sexual partners. Within Opiliones (Arachnida), several harvestmen in the suborder Laniatores have sexually dimorphic glands on legs I and IV, the mode of use of which is recorded only in two species but their function is unknown: while walking, males rub the glands against the substrate or against their body. Here we test an alternative and non-exclusive hypothesis that the glands present on the legs of male Gryne perlata (Cosmetidae) produce contact pheromones used in mating. We predicted that males would touch the females with the gland openings or with other male body parts previously rubbed by these glands. We also predicted that there are chemoreceptors on those parts of the females where males touch them. We analyzed 13 videos of G. perlata mating, a species in which the males have glands on legs I and IV of unknown function. We also analyzed 14 videos of Discocyrtus pectinifemur (Gonyleptidae) mating as a control, a species that lacks these glands. Finally, we looked for chemoreceptors on the legs of female G. perlata using a scanning electron microscope. During copulation, males of both species rubbed the legs of females with their first pair of legs, but not with the regions of these legs where the openings of the glands are. The fourth pair of legs were only used to support the body. Rubbing other body parts of the female by males with their glands was not observed during mating. Setae on the legs of the female did not have tip pores and therefore do not seem to be chemoreceptors. We therefore did not find any evidence that these sexually dimorphic glands in G. perlata release contact pheromones during mating. |
Morphological and molecular characterization of common European species of Adialytus (Hymenoptera: Braconidae: Aphidiinae) based on the mtCOI barcoding gene and geometric morphometrics of forewingsSa¹a S. STANKOVIÆ, Andjeljko PETROVIÆ, Marijana ILIÆ MILO©EVIÆ, Petr STARÝ, Nickolas G. KAVALLIERATOS, Vladimir ®IKIÆ, ®eljko TOMANOVIÆEur. J. Entomol. 112 (1): 165-174, 2015 | DOI: 10.14411/eje.2015.007 In this study three common European species of the genus Adialytus Förster, 1862 were examined: Adialytus ambiguus (Haliday, 1834), Adialytus salicaphis (Fitch, 1855) and Adialytus thelaxis (Starý, 1961). Molecular analysis involved the DNA barcoding of a region of the mitochondrial gene cytochrome oxidase I (COI). The genetic difference based on Kimura s two-parameter model for computing pairwise distances showed that A. thelaxis differs from both A. ambiguus and A. salicaphis by 4.9 and 6% on average, respectively. The genetic distance between A. ambiguus and A. salicaphis was 1.5% on average, suggesting that barcodes based on the COI gene are insufficiently informative for separating these two species. Geometric morphometrics analysis of forewing size and shape revealed statistically significant differences. The R1 vein on the forewing of A. ambiguus is more elongated than on the wings of A. salicaphis and A. thelaxis. The geometric morphometrics analysis of the forewings also revealed that A. salicaphis and A. thelaxis have much broader forewings, suggesting strong flight ability associated with their parasitizing arboricolous aphids. The distal part of the forewing of Adialytus ambiguus is narrower, which in this case suggests poor flight ability associated with parasitizing Sipha aphids on grasses. An illustrated key for identifying the European species of Adialytus is provided. |
Ability of males of two theclini species (Lepidoptera: Lycaenidae) to discriminate between sexes and different types of females based on the colour of their wingsMichio IMAFUKU, Tasuku KITAMURAEur. J. Entomol. 112 (2): 328-333, 2015 | DOI: 10.14411/eje.2015.034 Many territorial species of butterfly are sexually dimorphic in their wing colours, and males of such species frequently fight each other, probably attracted by the rival's wing colour. On the other hand, male behaviour should be directed to acquiring mates to increase their fitness, and thus should be sensitive to (usually cryptic) female wing colour. The present experiments aimed to determine whether the conspicuous male colour or cryptic female colour is more attractive to the territorial males of two lycaenid species, Chrysozephyrus smaragdinus and Neozephyrus japonicus. A pair of female and male wing models was presented simultaneously in the field to a male. The results indicate that the males of both species were preferentially attracted by the female wing model. In N. japonicus, in which the wing colour of females is polymorphic, males preferred particular types of female wings, in that they were more strongly attracted to the type-B model with a blue patch on the forewing than the type-O model, which lacked a blue patch. |
How does Oedipoda germanica (Orthoptera: Acrididae) cope on the northern edge of its distribution? A demographical study of a completely isolated populationStanislav RADA, Lucie ©TÌPÁNOVÁ, Jan LOSÍK, Jan ©IPO©, Jaroslav HOLU©A, Tomá¹ KURASEur. J. Entomol. 112 (3): 486-492, 2015 | DOI: 10.14411/eje.2015.062 We studied a population of the Red-winged grasshopper Oedipoda germanica, which is a highly stenotypic and endangered species in Central Europe. The locality studied is completely isolated and at the northern limit of this species distribution (north-west of the Czech Republic). We used capture-mark-recapture in 3 consecutive years (2008-2010). We estimated the total population size using POPAN software to be 136 adults in 2008, 70 in 2009 and 122 in 2010. Estimated daily survival rate (Ф) ranged from 0.950 to 0.987. We constructed linear mixed models to test for apparent survival in relation to temperature data. Temperatures (i.e. mean air temperature and maximum air temperature) were found to have significant effects on survival. The population studied is small, isolated and thus threatened by extinction, as are other O. germanica populations at the northern limit of their distribution. The preservation of indigenous populations in their localities can be achieved by active management, including the removal of shrubs and trees. |
Aphis pomi and Aphis spiraecola (Hemiptera: Sternorrhyncha: Aphididae) in Europe - new information on their distribution, molecular and morphological peculiaritiesRimantas RAKAUSKAS, Jekaterina BA©ILOVA, Rasa BERNOTIENĖEur. J. Entomol. 112 (2): 270-280, 2015 | DOI: 10.14411/eje.2015.043 Aphid species Aphis pomi (de Geer, 1773) is oligophagous on pomoideous host plants, whilst Aphis spiraecola Patch, 1914 is a polyphagous species alternating between Spiraea spp., its primary host, and a wide variety of secondary hosts, also including pomoideous species. Despite the biological distinction, these species are difficult to separate using their morphological characters. Partial sequences of mitochondrial COI and nuclear EF-1α genes were analyzed for samples from Central and Eastern Europe, Germany, Bulgaria, Italy, Turkey, China together with available data from GenBank. Interspecific pairwise sample divergences of the COI fragment ranged from 3.1 to 4.3%. One COI haplotype of A. pomi was predominant (n = 24), with a pan European distribution. The most abundant COI haplotype of A. spiraecola (n = 16) occurred in Lithuania, Latvia, Poland, Italy, Turkey and China. Interspecific pairwise sample divergences of the EF-1α fragment ranged from 0.6 to 1.2%. Analyzed partial sequences of EF-1α were identical in A. pomi. The most abundant EF-1α haplotype of A. spiraecola (n = 14) occurred in Lithuania, Poland, Italy, Turkey and China. The length of ultimate rostral segment appeared to be the most reliable morphological character for discrimination between apple and spirea aphid species. It allowed a 100% correct identification of A. pomi (n = 143) and 91.5% of A. spiraecola (n = 94) specimens in the European samples used for the molecular analysis. The existence of A. spiraecola in the Eastern Baltic region of Europe is documented for the first time. |
Effect of three species of host tree on the cold hardiness of overwintering larvae of Anoplophora glabripennis (Coleoptera: Cerambycidae)Original articleYuqian FENG, Reaxit TURSUN, Zhichun XU, Fang OUYANG, Shixiang ZONGEur. J. Entomol. 113: 212-216, 2016 | DOI: 10.14411/eje.2016.026 The Asian long-horned beetle, Anoplophora glabripennis, is a serious destructive pest of forests throughout China as it attacks a wide range of host plants. The effect of host trees on the cold hardiness of A. glabripennis larvae could be the basis for predicting the performance of this forest pest on different common hosts.To evaluate the effect of different species of host plant on the cold hardiness of overwintering larvae of A. glabripennis, we measured the supercooling point (SCP), fresh mass, protein content and concentrations of low molecular weight substances in overwintering larvae collected from three different host species (i.e., Populus opera, Populus tomentosa and Salix matsudana). Mean SCPs and protein contents of larvae from these three hosts differed significantly. The SCPs and protein contents of the larvae collected from P. opera and P. tomentosa were significantly higher than those collected from S. matsudana. The concentrations of glycerol, glucose and trehalose in overwintering larvae collected from these host species also differed significantly, but there were no significant differences in the concentrations of sorbitol and inositol. The larvae that were collected from S. matsudana had the highest concentrations of glycerol and trehalose and those from P. opera the lowest contents of glycerol, whereas those from P. tomentosa had the lowest concentrations of trehalose but the highest concentrations of glucose. Because of the significant differences in the quantities of these biochemical substances in their bodies, the cold hardiness of overwintering larvae of A. glabripennis was significantly dependent on the tree they fed on. These effects on the cold hardiness of the overwintering larvae might affect the selection of a host tree and therefore the spread of this beetle. |
Sociogenetic structure in nests of the mud dauber wasp Trypoxylon (Trypargilum) albitarse (Hymenoptera: Crabronidae)Antonio C. BRAGATO BERGAMASCHI, Juliano DA COSTA ALMEIDA, Lucio A. DE OLIVEIRA CAMPOS, Marco A. DEL LAMAEur. J. Entomol. 112 (4): 722-727, 2015 | DOI: 10.14411/eje.2015.092 Trypargilum is a subgenus of solitary spider-hunting wasps whose males guard the nest, an unusual behaviour for male wasps. A male pairs with a female and copulates repeatedly with her during the nesting process, although females regularly copulate with satellite males, which employ an alternative reproductive strategy. The purpose of this paper was to determine the sociogenetic structure in twenty-nine nests of Trypoxylon albitarse sampled at six sites in Brazil. A total of 367 wasps were genotyped for eight species-specific polymorphic microsatellite loci. Genotypic segregation analyses were conducted to test whether the nests sampled were monogamic family groups. The results indicated that all the offspring in 12 of the 29 nests could be attributed to a single couple (genetic monogamy). Approximately 9% of the offspring probably resulted from extra-pair copulations and 3% of the total offspring were attributed to a second mother (usurpation by conspecific females, a form of intraspecific parasitism). The sequential replacement of parents throughout the nesting process indicates that the 29 nests analyzed included 35 family groups. Thus, our findings indicate that Trypoxylon albitarse has a predominantly monogamous genetic mating system, despite the social polygamy reported in previous studies. |



