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Results 841 to 870 of 2340:

Causes of polymorphic melanism and its thermoregulatory function in a parasitoid wasp Meteorus pulchricornis (Hymenoptera: Braconidae)

Yosuke ABE, Takuma NISHIMURA, Kaoru MAETO

Eur. J. Entomol. 110 (4): 627-632, 2013 | DOI: 10.14411/eje.2013.085

We investigated the variation in body colour and its thermoregulatory function in Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae), a parasitoid wasp of Spodoptera and other free-living lepidopteran larvae. We show that the body colour of adult wasps darkens when cocoons are kept at low temperatures. The range in the variation in colour, however, differs for different parts of the body and among uniparental (thelytokous) strains. This melanism enables these wasps to attain a body temperature in sunshine up to 2°C. Moreover, this small gain in body temperature can markedly increase the flight activity of wasps at low ambient temperatures. We conclude that the variation in body colour that resulted from rearing the cocoons at different temperatures enable the wasps to adapt to changing thermal environments. The ecological significance of the difference in the degree of melanism of the different strains is discussed.

Phylogenetic relatedness of Erebia medusa and E. epipsodea (Lepidoptera: Nymphalidae) confirmed

Martina ©EMELÁKOVÁ, Peter PRISTA©, ¥ubomír PANIGAJ

Eur. J. Entomol. 110 (2): 379-382, 2013 | DOI: 10.14411/eje.2013.049

The extensive genus Erebia is divided into several groups of species according to phylogenetic relatedness. The species Erebia medusa was assigned to the medusa group and E. epipsodea to the alberganus group. A detailed study of the morphology of their copulatory organs indicated that these species are closely related and based on this E. epipsodea was transferred to the medusa group. Phylogenetic analyses of the gene sequences of mitochondrial cytochrome C oxidase subunit I (COI) and mitochondrial NADH dehydrogenase subunit 1 (ND1) confirm that E. medusa and E. epipsodea are closely related. A possible scenario is that the North American species, E. episodea, evolved after exclusion/isolation from E. medusa, whose current centre of distribution is in Europe.

Relationships between locomotor activity, oxidative damage and life span in males and females of the linden bug, Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)

Marcela BURICOVA, Magdalena HODKOVA

Eur. J. Entomol. 110 (3): 443-449, 2013 | DOI: 10.14411/eje.2013.059

In this study we addressed a question of whether experimental manipulations that increase life span also reduce physical activity and molecular oxidative damage. We used three phenotypes of male and female Pyrrhocoris apterus that survive for different lengths of time, diapausing insects, reproductive insects and insects from which the corpus allatum, the source of juvenile hormone, was surgically removed. Protein carbonyl content of the thoracic muscles was used as an index of molecular oxidative modification. Diapause or ablation of the corpus allatum (allatectomy) was associated with an extended life span of both sexes, but only those individuals that were in diapause were less active. The carbonyl content, both relative (per protein unit) and absolute (per thorax) increased with age in reproductive insects of both sexes. However, the associations between the carbonyl content and diapause and allatectomy differed in males and females. In males, the carbonyl content was not associated with either diapause or allatectomy. There was no age-related increase in the relative and absolute carbonyl levels in diapausing females, while only the increase in the relative carbonyl level was absent in allectomized females. Overall, the results indicate that both allatectomy and diapause prolonged life span, but had different and sex-specific effects on locomotor activity and carbonyl content. Only the extension of the life span of diapausing females was correlated with both reduced locomotor activity and reduced carbonyl content.

Cost to the cavity-nest ant Temnothorax crassispinus (Hymenoptera: Formicidae) of overwintering aboveground

S³awomir MITRUS

Eur. J. Entomol. 110 (1): 177-179, 2013 | DOI: 10.14411/eje.2013.026

Most species of ants inhabiting the temperate zone overwinter underground, whereas those of the genus Temnothorax remain in nests aboveground. I studied the cost of aboveground overwintering. Workers of Temnothorax crassispinus survived in higher numbers (median = 88%) in artificial nests experimentally buried at a depth of 5 cm than those in nests on the surface (48%) of the soil. The results support the hypothesis that overwintering aboveground could be a consequence of a limited supply of nests and/or the advantage of being able to respond quickly to warm temperatures in spring.

Vibratory territorial signals in caterpillars of the poplar lutestring, Tethea or (Lepidoptera: Drepanidae)

Jaclyn L. SCOTT, Jayne E. YACK

Eur. J. Entomol. 109 (3): 411-417, 2012

Caterpillars of the poplar lutestring moth, Tethea or, construct leaf shelters that they defend against intruding conspecifics using a combination of vibratory signals and physical aggression. Staged interactions between a resident caterpillar and introduced conspecific were recorded with a video camera and laser vibrometer. Residents crawl towards the intruder and perform three behaviours: lateral hitting, pushing, and mandible scraping. Vibrations caused by mandible scraping result from the caterpillar repeatedly scraping opened mandibles laterally against the leaf surface in bouts lasting 1.16 ± 0.39 s, with an average of 4 ± 1 scrapes per bout. We propose that these scrapes function in leaf shelter defense against conspecifics for the following reasons: Mandible scrapes are produced only by residents; they are generated when a resident is approached by an intruder; the rate of scraping increases as the intruder approaches the shelter; and residents in all trials retain their shelters, with the intruder leaving the leaf within 127.9 ±104.3s from the beginning of the trial. The function and evolutionary origins of vibration-mediated territoriality in caterpillars are discussed.

Correlations between landscape attributes and ecological traits of Lepidoptera communities in olive groves

Stefano SCALERCIO, Pietro BRANDMAYR, Nino IANNOTTA, Ruggero PETACCHI, Luigi BOCCACCIO

Eur. J. Entomol. 109 (2): 207-216, 2012 | DOI: 10.14411/eje.2012.027

The effects of landscape attributes on Lepidoptera communities were studied in an agricultural area in Calabria (S-Italy). The association between a set of community descriptors and landscape metrics was determined using a multi-scale approach. Lepidoptera were sampled using yellow sticky traps in 10 olive groves. The landscape in 5 concentric areas, with radii from 250 to 1250 m, around each sampling site was analyzed. The composition and configuration of the landscape were calculated both at the landscape and class level based on the main classes of land use. The following life-history traits of Lepidoptera were considered: (i) dispersal ability of adults, (ii) habitat preferences and (iii) diet breadth of larvae. An index of community vulnerability was calculated by combining life-history traits and species diversity. There were no significant correlations between any of the landscape metrics and species richness or between species richness and abundance of natural or semi-natural habitats. However, life-history traits were significantly correlated with some landscape metrics, depending on the spatial scale. Most notably, landscape diversity is positively correlated with community vulnerability. The presence of sensitive species in olive orchards, but not species richness per se, is associated with the presence of natural and semi-natural habitats in the surrounding agricultural landscape. In conclusion, responses of communities to landscape changes are more likely to be revealed by an analysis of ecological traits, than species richness. In particular, the vulnerability index, used in this joint analysis of the main ecological traits, seems to be an effective descriptor of the relationships between communities and landscape.

Biogeography of tenebrionid beetles (Coleoptera: Tenebrionidae) in the circum-Sicilian islands (Italy, Sicily): Multiple biogeographical patterns require multiple explanations

Simone FATTORINI

Eur. J. Entomol. 108 (4): 659-672, 2011 | DOI: 10.14411/eje.2011.084

The tenebrionid beetles on 25 circum-Sicilian islands were studied to determine the influence of island geographical and landscape features on three main intercorrelated biogeographical patterns: (1) species richness, studied using species-area and species environment relationships, (2) species assemblage composition, investigated using Canonical Correspondence Analysis (CCA), and (3) inter-site faunal similarity, investigated using Canonical Correlation Analysis (CANCOR) applied to multidimensional scaling of inter-island faunal dissimilarities. Species richness was mostly influenced by island area and landscape heterogeneity (expressed using various indices of diversity based on land cover categories). When species identities were considered in the CCA, no substantial effect of landscape was detected. Current island isolation did not have a strong influence on species richness, but has a distinct effect in determining species assortments on the remotest islands. Historical influences of Pleistocene landbridge connections were not detectable in species richness relationships using geographical variables in species richness analyses or in assemblage gradients in the CCA, but emerged distinctly from inter-island similarities in the CANCOR.

Vertical stratification and microhabitat selection by the Great Capricorn Beetle (Cerambyx cerdo) (Coleoptera: Cerambycidae) in open-grown, veteran oaks

Jan ALBERT, Michal PLATEK, Lukas CIZEK

Eur. J. Entomol. 109 (4): 553-559, 2012 | DOI: 10.14411/eje.2012.069

The great capricorn beetle or Cerambyx longicorn (Cerambyx cerdo, Linnaeus, 1758) is an internationally protected umbrella species representing the highly diverse and endangered fauna associated with senescent oaks. For the conservation and monitoring of populations of C. cerdo it is important to have a good knowledge of its microhabitat requirements. We investigated determinants and patterns of C. cerdo distribution within individual old, open-grown oaks. Trees inhabited by this species were climbed, and the number of exit holes and environmental variables recorded at two sites in the Czech Republic. Distribution of exit holes in relation to height above the ground, trunk shading by branches, orientation in terms of the four cardinal directions, diameter, surface and volume of inhabited tree parts were investigated. This study revealed that the number of exit holes in the trunks of large open-grown oaks was positively associated with the diameter of the trunk and openness and negatively with height above the ground, and the effects of diameter and openness changed with height. The number of exit holes in the surface of a trunk was also associated with the cardinal orientation of the surface. Approximately half of both C. cerdo populations studied developed less than 4 m and approximately a third less than 2 m above the ground. This indicates that most C. cerdo develop near the ground. Active management that prevents canopy closure is thus crucial for the survival of C. cerdo and searching for exit holes is an effective method of detecting sites inhabited by this species.

The two spotted spider mite, Tetranychus urticae (Acari: Tetranychidae), alternative prey for the lacewing Dichochrysa prasina (Neuroptera: Chrysopidae)

Maria L. PAPPAS, Georgios D. BROUFAS, Dimitris S. KOVEOS

Eur. J. Entomol. 105 (3): 461-466, 2008 | DOI: 10.14411/eje.2008.059

The predatory lacewing Dichochrysa prasina Burmeister can feed and reproduce on various aphid species. However, other species such as the two spotted spider mite Tetranychus urticae Koch may serve as an alternative prey for this predator in the field in periods when the population density of aphids is low. In peach orchards in Northern Greece D. prasina larvae are often found during the summer months on leaves infested with T. urticae. The development and reproduction of D. prasina fed on T. urticae at a series of different constant temperatures were studied. The percentages of D. prasina larvae that completed their development when fed on T. urticae ranged from 12 to 60% depending on the temperature over the range from 20 to 30°C, whereas at temperatures above 33°C no larvae survived. Longevity and egg production of D. prasina females fed during the larval stages on T. urticae were also determined and certain demographic parameters such as the intrinsic rate of increase (rm), mean generation time and net reproductive rate were estimated. Over the range of temperatures from 20 to 27°C, the rm values were not significantly different and varied from 0.06629 to 0.07030. Based on the results of the present study, the possible effect of the availability of T. urticae as prey for D. prasina during summer, when its main prey species is scarce, is discussed.

BOOK REVIEW: Choe J. 2012: SECRET LIVES OF ANTS.

J. ®ÏÁREK

Eur. J. Entomol. 110 (2): 240, 2013 | DOI: 10.14411/eje.2013.034

Choe J. 2012: SECRET LIVES OF ANTS. The Johns Hopkins University Press, Baltimore, MD, 156 pp. ISBN-13-978-1-4214-0428-8 (hard cover). Price USD 34.95.

BOOK REVIEW: Strausfeld N.J. 2012: ARTHROPOD BRAINS. EVOLUTION, FUNCTIONAL ELEGANCE, AND HISTORICAL SIGNIFICANCE.

B. HEMING

Eur. J. Entomol. 110 (2): 389-390, 2013 | DOI: 10.14411/eje.2013.050

Strausfeld N.J. 2012: ARTHROPOD BRAINS. EVOLUTION, FUNCTIONAL ELEGANCE, AND HISTORICAL SIGNIFICANCE. The Belknap Press of Harvard University Press, Cambridge and London, xvi + 830 pp., 175 color illustrations, 24 halftones, glossary, extensive notes. ISBN 978-0-674-04633-7, hardbound. Price USD 65.00.

Temperature dependent functional response of Diaeretiella rapae (Hymenoptera: Aphidiidae) to the cabbage aphid, Brevicoryne brassicae (Hemiptera: Aphididae)

Hamid R.S. MOAYERI, Hossein MADADI, Hossein POURASKARI, Annie ENKEGAARD

Eur. J. Entomol. 110 (1): 109-113, 2013 | DOI: 10.14411/eje.2013.015

Diaeretiella rapae MacIntosh (Hymenoptera: Aphidiidae) is one of the most common and successful parasitoids of the cabbage aphid. The functional response of D. rapae towards cabbage aphids was examined in laboratory studies at three constant temperatures, 17°C, 25°C and 30°C. D. rapae exhibited a type II functional response at all three temperatures. The search rates were uninfluenced by temperature whereas handling times differed significantly between 17°C and 25°C, and between 17°C and 30°C, but not between 25°C and 30°C. This study is a first-step in the evaluation of the effectiveness of D. rapae as a biocontrol agent of Brevicoryne brassicae at different temperatures.

Characterization and evaluation of microsatellite markers in a strain of the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), with a genetic sexing character used in sterile insect population control

Siriwan ISASAWIN, Nidchaya AKETARAWONG, Sujinda THANAPHUM

Eur. J. Entomol. 109 (3): 331-338, 2012

The oriental fruit fly, Bactrocera dorsalis, is a key economic insect pest reducing fruit yield and generating constraints in the international market. The application of the sterile insect technique (SIT) continues to reveal areas where new technologies can improve the effectiveness of fruit fly control. One such advancement concerns insect strains. In the present study, a mass-reared strain of the fly with a translocation-based genetic sexing character (Salaya1) based on a brown-white pupal colour dimorphism was genetically characterized using 11 microsatellite DNA markers. Subsequently, these markers were used to evaluate the maintenance of genetic variability in the strain under mass-rearing conditions. Mating competitiveness of this strain was also tested in field cages. Two of the newly characterized Y-pseudo-linked microsatellite markers were used for strain identification in field monitoring traps. The strain was also validated in a pilot integrated pest management (IPM) programme using male-only SIT in a fruit orchard. The programme resulted in the suppression of the fruit fly population.

Parasitism and migration in southern Palaearctic populations of the painted lady butterfly, Vanessa cardui (Lepidoptera: Nymphalidae)

Constantí STEFANESCU, Richard R. ASKEW, Jordi CORBERA, Mark R. SHAW

Eur. J. Entomol. 109 (1): 85-94, 2012 | DOI: 10.14411/eje.2012.011

The painted lady butterfly (Vanessa cardui) (Lepidoptera: Nymphalidae: Nymphalinae) is well known for its seasonal long-distance migrations and for its dramatic population fluctuations between years. Although parasitism has occasionally been noted as an important mortality factor for this butterfly, no comprehensive study has quantified and compared its parasitoid complexes in different geographical areas or seasons. In 2009, a year when this butterfly was extraordinarily abundant in the western Palaearctic, we assessed the spatial and temporal variation in larval parasitism in central Morocco (late winter and autumn) and north-east Spain (spring and late summer). The primary parasitoids in the complexes comprised a few relatively specialized koinobionts that are a regular and important mortality factor in the host populations. However, there was a strong seasonal variation in the level of parasitism. In Spain percentage parasitism was more than four times higher in late summer than in spring (77.3% vs. 18%), while in Morocco it was five times higher by the end of winter than in the autumn (66.2% vs. 13.2%). In both regions the build up of parasitoid populations occurred after V. cardui had bred in the same general area over successive generations, and this may represent a selective force favouring seasonal migration to enemy-free space.

Population genetics and demographic history of guava fruit fly Bactrocera correcta (Diptera: Tephritidae) in northeastern Thailand

Chonticha KUNPROM, Piyamas NANORK SOPALADAWAN, Pairot PRAMUAL

Eur. J. Entomol. 112 (2): 227-234, 2015 | DOI: 10.14411/eje.2015.033

Bactrocera correcta (Bezzi) is among the most destructive fruit fly pests of the genus Bactrocera. This species infests 62 species of plants belonging 30 families, many of which are commercially important. In this study, the genetic structure, diversity and demographic history of B. correcta in Thailand were inferred from mitochondrial cytochrome c oxidase I (COI) sequences. High genetic diversity was recorded in the 171 samples collected from 15 locations. This was due largely to the existence of two divergent lineages (I, II) revealed by median joining (MJ) network analysis. Genetic structure analysis revealed an overall low level of genetic differentiation between populations suggesting that the flies can move freely across geographic regions. Because the host plants are commonly grown in Thailand, continuity of habitats is the factor most likely responsible for the genetic homogeneity. In addition, the recent population history could also be a factor that contributed to the overall low level of the genetic structure. Mismatch distribution analysis as well as Tajima's D and Fu's FS tests detected evidence of recent demographic expansion dating back to the end of the last glaciations.

Isolation and characterization of novel microsatellite loci in the genome of the dragonhead sap beetle Thymogethes norvegicus (Coleoptera: Nitidulidae)Note

Oddmund KLEVEN, Anders ENDRESTØL

Eur. J. Entomol. 113: 528-530, 2016 | DOI: 10.14411/eje.2016.071

Here we describe 16 novel microsatellite loci in the genome of the dragonhead sap beetle Thymogethes norvegicus, which were identified using a next-generation sequencing approach. In 40 dragonhead sap beetles from a population in southern Norway, we found 2-4 alleles per locus. Expected heterozygosity ranged from 0.18-0.65. Three of the loci showed significant deviation from Hardy-Weinberg equilibrium. After correcting for multiple tests, one pairwise locus combination displayed significant linkage disequilibrium. These novel microsatellite loci will be useful for future population structure, genetic diversity and conservation genetic studies of the dragonhead sap beetle.

How differences in the settling behaviour of moths (Lepidoptera) may contribute to sampling bias when using automated light trapsOriginal article

Mirko WÖLFLING, Mira C. BECKER, Britta UHL, Anja TRAUB, Konrad FIEDLER

Eur. J. Entomol. 113: 502-506, 2016 | DOI: 10.14411/eje.2016.066

Quantitative community-wide moth surveys frequently employ flight-interception traps equipped with UV-light emitting sources as attractants. It has long been known that moth species differ in their responsiveness to light traps. We studied how the settling behaviour of moths at a light trap may further contribute to sampling bias. We observed the behaviour of 1426 moths at a light tower. Moths were classified as either, settling and remaining still after arrival, or continually moving on the gauze for extended periods of time. Moths that did not move after settling may not end up in the sampling container of the light trap and therefore are under-represented in automated trap samples relative to their true proportions in the community. Our analyses revealed highly significant behavioural differences between moths that differed in body size. Small moths were more likely to remain stationary after settling. As a corollary, representatives of three taxa, which in Europe are predominantly small species (Nolidae, Geometridae: Eupitheciini, Erebidae: Lithosiini), usually settled down immediately, whereas most other moths remained active on or flying around the trap for some time. Moth behaviour was also modulated by ambient temperature. At high temperatures, they were less likely to settle down immediately, but this behavioural difference was most strongly apparent among medium-sized moths. These results indicate the likely extent of the sampling bias when analysing and interpreting automated light-trap samples. Furthermore, to control for temperature modulated sampling bias temperature should always be recorded when sampling moths using flight-interception traps.

Book review: Vega F.E. & Hofstetter R.W. (eds) 2015: Bark Beetles: Biology and Ecology of Native and Invasive Species, 1st ed.Book review

M. KNͮEK

Eur. J. Entomol. 113: 307-308, 2016 | DOI: 10.14411/eje.2016.038

Vega F.E. & Hofstetter R.W. (eds) 2015: Bark Beetles: Biology and Ecology of Native and Invasive Species, 1st ed. Elsevier, Academic Press, Amsterdam, Boston, Heidelberg, London, New York, Oxford, Paris, San Diego, San Francisco, Singapore, Sydney, Tokyo, 640 pp. ISBN 9780124171565. Price EUR 92.95.

Tettigoniidae (Orthoptera) ovipositing in old galls of Dryocosmus kuriphilus (Hymenoptera: Cynipidae)Note

Giuliano CERASA, Bruno MASSA

Eur. 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.

Changes in ladybird (Coleoptera: Coccinellidae) communities along a steep pollution gradient in subarctic forests of European Russia

Mikhail V. KOZLOV

Eur. J. Entomol. 112 (4): 728-733, 2015 | DOI: 10.14411/eje.2015.075

Industrial air pollution constitutes a major environmental disturbance, and its impacts on insect communities have considerable implications for ecosystem structure and functions. Existing information on insect responses to pollution generally addresses abundant taxa, whereas few studies examine the effects of pollution on rare species. To begin rectifying this bias, ladybirds (Coleoptera: Coccinellidae) were quantitatively collected annually from 2002-2014 in 13 sites located 0.7 to 39.7 km from the nickel-copper smelter in Monchegorsk, north-western Russia. Seven of eight recorded species were found only in severely and /or moderately polluted sites. Both Shannon's diversity index and coccinellid abundance decreased with increasing distance from the smelter. Thus, some groups of predatory insects, in particular the Coccinellidae, may benefit from environmental changes caused by severe industrial pollution, whereas the most abundant invertebrate predators generally suffer from such changes.

Reproductive status of Tribolium castaneum (Coleoptera: Tenebrionidae) affects its response to infection by Steinernema feltiae (Rhabditida: Steinernematidae)Original article

Paulina KRAMARZ, Dariusz MA£EK, Maria GAWE£, Szymon M. DROBNIAK, Joanna HOMA

Eur. 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.

Depilation increases while hairiness decreases the risk of drowning: A hitherto unappreciated survival role of setae in woolly bear caterpillars of the moth Lemyra imparilis (Lepidoptera: Noctuoidea: Erebidae)Note

V. Benno MEYER-ROCHOW

Eur. J. Entomol. 113: 130-134, 2016 | DOI: 10.14411/eje.2016.016

This note aims to put on record a hitherto unreported function of caterpillar setae supplementary to those already known. When woolly bear caterpillars of the moth Lemyra imparilis (Butler) have their body hairs removed and are dropped into a bucket of water from a height of 30 cm, they sink immediately. Caterpillars, however, with an intact coat of hairs usually float. This hitherto unreported role of caterpillar setae as life-rafts should depend on a high contact angle θe, and thus on the position, density and dimensions of the hairs. An SEM examination of the surface structure of the setae revealed a system of fine grooves and small distally pointing barbs on the hair shaft, which can trap air to support the weight of the insect. Insect setae generally and body hairs of caterpillars in particular are known to possess many functions, but a role as life-rafts for caterpillars in danger of drowning can now be added to the list of possible uses of body hairs.

Larvae of the water scavenger beetle, Hydrophilus acuminatus (Coleoptera: Hydrophilidae) are specialist predators of snails

Toshio INODA, Yuta INODA, June Kathyleen RULLAN

Eur. J. Entomol. 112 (1): 145-150, 2015 | DOI: 10.14411/eje.2015.016

Hydrophilus acuminatus larvae are known to feed on aquatic prey. However, there is no quantitative study of their feeding habits. In order to determine the feeding preferences and essential prey of larvae of H. acuminatus, both field and laboratory experiments were carried out. Among the five potential species of prey, Austropeplea ollula (Mollusca: Lymnaeidae), Physa acuta (Mollusca: Physidae), Asellus hilgendorfi (Crustacea: Asellidae), Palaemon paucidens (Crustacea: Palaemonidae) and larvae of Propsilocerus akamusi (Insecta: Chironomidae), the first instar larvae of H. acuminatus strongly prefered the Austropeplea and Physa snails in both cafeteria and single-prey species experiments. Larvae that were provided with only snails also successfully developed into second instar larvae, while larvae fed Palaemon, Propsilocerus larvae or Asellus died during the first instar. In addition, the size of adult H. acuminatus reared from first-instar larvae and fed only snails during their entire development was not different from that of adult H. acuminatus collected in the field. This indicates that even though the larvae of H. acuminatus can feed on several kinds of invertebrates, they strongly prefer snails and without them cannot complete their development.

Nutrient-specific food selection buffers the effect of nutritional imbalance in the mealworm beetle, Tenebrio molitor (Coleoptera: Tenebrionidae)

Myung Suk RHO, Kwang Pum LEE

Eur. 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.

Book review: Smith D.A.S. 2014: African Queens and their Kin. A Darwinian Odyssey.Book review

Z. FALTÝNEK FRIC

Eur. J. Entomol. 113: 98, 2016 | DOI: 10.14411/eje.2016.011

Smith D.A.S. 2014: African Queens and their Kin. A Darwinian Odyssey. Brambleby Books, Tauton, Somerset, 848 pp. ISBN 9781908241153. Price GBP 90.00.

Book Review: Gandy M. 2016: Moth. Dodd A. 2016: Beetle.Book review

J. ®ÏÁREK

Eur. J. Entomol. 113: 523, 2016 | DOI: 10.14411/eje.2016.069

Gandy M. 2016: Moth. Reaktion Books, London, 240 pp., 120 illustrations, 103 in colour. ISBN 978-1-78023-585-1 (pbk). Price GBP 12.95.
Dodd A. 2016: Beetle. Reaktion Books, London, 192 pp., 102 illustrations, 80 in colour. ISBN 978-1-78023-488-5 (pbk). Price GBP 12.95.

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 ULRICH

Eur. 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.

Is the type of soil an important factor determining the local abundance of carrion beetles (Coleoptera: Silphidae)?

Pavel JAKUBEC, Jan RÙ®IÈKA

Eur. J. Entomol. 112 (4): 747-754, 2015 | DOI: 10.14411/eje.2015.071

Carrion beetles (Coleoptera: Silphidae) provide a valuable ecosystem service by promoting nutrient cycling and controlling pests like noxious flies (Diptera: Calliphoridae and Sarcophagidae). Our main goal was to examine the relationship between the occurrence of carrion beetles and soil type. We used pitfall traps to collect 43,856 specimens of 15 species of carrion beetles in the Czech Republic during 2009. We found that the abundance of seven of the carrion beetles - Nicrophorus antennatus (Reitter), N. germanicus (Linnaeus), N. humator (Gleditsch), N. interruptus (Stephens), N. sepultor (Charpentier), Silpha obscura obscura (Herbst) and T. sinuatus (Fabricius) - was significantly higher either in areas with chernozem or fluvisol soils. These findings support our hypothesis that soil type could be an important factor determining the occurrence of necrophagous European carrion beetles. Our findings could be helpful when selecting important nature conservation sites (particularly inasmuch as N. antennatus, N. germanicus and N. sepultor are listed as endangered species on the Czech Red List of Invertebrates) as in this respect localities where there are chernozem soils are potentially valuable.

Chromosome fusion polymorphisms in the grasshopper, Dichroplus fuscus (Orthoptera: Acrididae: Melanoplinae): Insights on meiotic effects

Alberto TAFFAREL, Claudio J. BIDAU, Dardo A. MARTÍ

Eur. J. Entomol. 112 (1): 11-19, 2015 | DOI: 10.14411/eje.2015.010

Robertsonian fusions account for many of the changes in the evolution of the orthopteran karyotype; in their origin, a centric fusion is involved between two acro-telocentric chromosomes, forming a single bi-armed chromosome. It is usual for these rearrangements to be associated with profound changes in meiosis, such as modification in frequency and distribution of chiasmata. Dichroplus fuscus is a South American grasshopper with a wide distribution. In this work we analyzed nine populations from Misiones Province, north-eastern Argentina. This species presents a standard karyotype of 2n = 23/24 (♂/♀) with all chromosomes acro-telocentric and an X0/XX chromosomal sex determining mechanism. This standard karyotype has been modified by the occurrence of two Robertsonian fusions involving chromosomes 1/3 and 2/4; values of fusions per individual (fpi) show a significant increase in the presence of karyotypic polymorphisms towards southern populations. In individuals showing chromosomal rearrangements, we observed a clear redistribution of chiasmata towards distal positions; significant differences were noted between Robertsonian homozygotes (Ho) and heterozygotes (Ht) for chromosomes arms L1 and M3, although this was not the case between Ho and Ht for chromosome arms L2 and M4. With regard to the orientation of trivalents, values obtained for non-convergent orientation were low.

Book Review: Pearson D.L., Knisley C.B., Duran D.P. & Kazilek C.J. 2015: A Field Guide to the Tiger Beetles of the United States and Canada. Identification, Natural History, and Distribution of the Cicindelinae. 2nd ed.Book review

R. JASKU£A

Eur. J. Entomol. 113: 344, 2016 | DOI: 10.14411/eje.2016.044

Pearson D.L., Knisley C.B., Duran D.P. & Kazilek C.J. 2015: A Field Guide to the Tiger Beetles of the United States and Canada. Identification, Natural History, and Distribution of the Cicindelinae. 2nd ed. Oxford University Press, New York, 251 pp. ISBN 978-0-19-936717-7. Price USD 35.44.

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