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Results 751 to 780 of 2340:

How fine is fine-scale? Questioning the use of fine-scale bioclimatic data in species distribution models used for forecasting abundance patterns in butterflies

Katharina J. FILZ, Thomas SCHMITT, Jan O. ENGLER

Eur. J. Entomol. 110 (2): 311-317, 2013 | DOI: 10.14411/eje.2013.044

The use of species distribution models (SDMs) to predict the spatial occurrence and abundance of species in relation to environmental predictors has been debated in terms of species' ecology and biogeography. The predictive power of these models is well recognized for vertebrates, but has not yet been tested for invertebrates. In this study, we aim to assess the use of SDMs for predicting local abundances of invertebrates at a macroscale level. A maximum entropy algorithm was used to build SDMs based on occurrence records of 61 species of butterflies and bioclimatic information with a 30 arc second resolution. Predictions of habitat suitability were correlated with butterfly abundance data derived from independently conducted field surveys in order to check for a relationship between the predictions of the model and local abundances. Even though the model accurately described the current distributions of the species in the study area at a macroscale, the observed occurrences of the species (i.e. presence/absence) recorded by the field surveys differed significantly from the model's predictions for the corresponding grid cells. Moreover, there was no correlation between observed abundance and the model's predictions for most species of butterflies. We conclude that the spatial abundance of butterflies cannot be predicted from environmental suitability modelled at a resolution as large as in this study. Using the finest scale bioclimatic information currently available (i.e. 30 arc seconds) it is not adequate to predict species abundances as structural and ecological factors as well as climatic patterns acting at a smaller scale are key determinants of the occurrence and abundance of invertebrates. Therefore, future studies have to account for the role of the resolution in environmental predictors when assessments of spatial abundances via SDMs will be conducted.

Harmonia axyridis (Coleoptera: Coccinellidae) as a host of the parasitic fungus Hesperomyces virescens (Ascomycota: Laboulbeniales, Laboulbeniaceae): A case report and short review

Piotr CERYNGIER, Kamila TWARDOWSKA

Eur. J. Entomol. 110 (4): 549-557, 2013 | DOI: 10.14411/eje.2013.075

Hesperomyces virescens is an ectoparasite of some Coccinellidae, which until the mid-1990s was relatively rarely only reported from warm regions in various parts of the world. Analysis of the host and distribution data of H. virescens recorded in the Western Palaearctic and North America reveals several trends in the occurrence and abundance of H. virescens: (1) it has recently been much more frequently recorded, (2) most of the recent records are for more northerly (colder) localities than the early records and (3) the recent records are mostly of a novel host, the invasive harlequin ladybird (Harmonia axyridis). While in North America H. virescens is almost exclusively found on H. axyridis, all European records of this association are very recent and still less numerous than records of Adalia bipunctata as a host. However, based on a relatively few published cases of the H. axyridis-H. virescens association in Europe and the case described in this paper, it is clear that the harlequin ladybird is currently the main host of this parasite. These changes in the abundance and geographical distribution of H. virescens are probably linked to some features of H. axyridis, such as its abundance, multivoltinism with overlapping generations, high level of promiscuity and overwintering in mass aggregations. The occurrence of these features in one species may make it especially suitable for H. virescens and other parasites that require close contact of host individuals for efficient transmission. Indeed, some of the data indicate that parasites other than H. virescens, like the podapolipid mite Coccipolipus hippodamiae and allantonematid nematodes of the genus Parasitylenchus may also heavily parasitize H. axyridis. We hypothesize that the acquisition of H. axyridis as a host by H. virescens, C. hippodamiae and Parasitylenchus spp. may have further consequences for the abundance and distribution of these parasites, including the expansion of their ranges to other continents colonized by invasive populations of this ladybird and areas in Asia where H. axyridis is native.

Chromosomal characteristics and evolutionary relationships of the Palearctic black fly Simulium carthusiense (Diptera: Simuliidae)

Peter H. ADLER, Gunther SEITZ

Eur. J. Entomol. 111 (4): 469-474, 2014 | DOI: 10.14411/eje.2014.066

The giant, polytene chromosomes of Simulium carthusiense Grenier & Dorier, 1959 were mapped, and all rearrangements were resolved relative to the standard banding sequence for the S. vernum group. The species is chromosomally cohesive from Austria to Spain, and is characterized by a chromocenter, two unique fixed inversions, 10 unique autosomal polymorphisms, and undifferentiated sex chromosomes. Rare individuals (3%) have two types of supernumerary chromosomes, representing the third example of a simuliid species that carries two different supernumeraries in the same individuals. Band-sequence comparisons with chromosomal outgroups indicate that S. carthusiense is the sister species of a clade that includes S. beltukovae (Rubtsov, 1956), the S. cryophilum complex, and S. urbanum Davies, 1966.

Cytogenetic characterization of Diachasmimorpha longicaudata (Hymenoptera: Braconidae), a parasitoid wasp used as a biological control agent

Leonela CARABAJAL PALADINO, Alba PAPESCHI, Silvia LANZAVECCHIA, Jorge CLADERA, María José BRESSA

Eur. J. Entomol. 110 (3): 401-409, 2013 | DOI: 10.14411/eje.2013.054

Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a parasitoid wasp widely used in the biological control of fruit flies. In this paper, we present a detailed analysis of the karyotype of this species based on the results of classical and molecular cytogenetic techniques. The cytogenetic analysis confirmed the male and female chromosome numbers previously reported (n = 20, 2n = 40). The entire short arm of most chromosomes is made up of a large constitutive heterochromatic segment. The high heterochromatin content differentiates D. longicaudata from other braconid species. Fluorescence in situ hybridization (FISH) using autologous 18S rDNA probes revealed six clusters of rDNA, i.e. six nucleolar organizer regions (NORs), in the heterochromatic short arms of different chromosomes in the haploid male karyotype. This number is exceptionally high for Hymenoptera, which usually have two NORs in the diploid complement. It is noteworthy that these rDNA-FISH experiments represent the first use of this technique on a braconid species using autologous probes. Since Ag-NOR-bands were coincident with C-positive bands on metaphase chromosomes, it was not possible to identify active nucleoli. The physical characteristics of the D. longicaudata karyotype, especially the content and distribution of heterochromatin and the number and location of rDNA clusters, contribute to a better understanding of the structure and organization of braconid chromosomes and provide a basis for genomic and evolutionary studies.

Ovaries of Puto superbus and Ceroputo pilosellae (Hemiptera: Coccoidea): Morphology, ultrastructure, phylogenetic and taxonomic implications

Anna MICHALIK, Małgorzata KALANDYK-KOŁODZIEJCZYK, Ewa SIMON, Michał KOBIAŁKA, Teresa SZKLARZEWICZ

Eur. J. Entomol. 110 (3): 527-534, 2013 | DOI: 10.14411/eje.2013.070

Ovaries of Puto superbus and Ceroputo pilosellae are composed of numerous short telotrophic ovarioles that are arranged around the distal part of the lateral oviduct. An individual ovariole consists of a distal trophic chamber (= tropharium) and proximal vitellarium. The tropharia enclose individual trophocytes (= nurse cells) and early previtellogenic oocytes termed arrested oocytes. A single oocyte develops in each vitellarium. Analysis of serial sections has shown that ovarioles of P. superbus contain from 16 to 51 germ cells (13-43 trophocytes, 2-7 arrested oocytes, 1 developing oocyte) while those of C. pilosellae from only 8 to 10 germ cells (5-7 trophocytes, 0-2 arrested oocytes, 1 developing oocyte). The classification and phylogeny of scale insects are discussed taking into consideration the results of this study.

How much care does a shrub-feeding hairstreak butterfly, Satyrium spini (Lepidoptera: Lycaenidae), need in calcareous grasslands?

Franz LÖFFLER, Gregor STUHLDREHER, Thomas FARTMANN

Eur. J. Entomol. 110 (1): 145-152, 2013 | DOI: 10.14411/eje.2013.020

Many butterfly target species are associated with early successional stages of grasslands. The Blue-spot Hairstreak, Satyrium spini (Denis & Schiffermüller, 1775), is a target species of grasslands. However, it feeds on Common Buckthorn (Rhamnus cathartica), which is associated with late successional stages of grasslands. If S. spini would also be restricted to late seral stages, there might be a management dilemma due to the contrasting requirements of S. spini and other target species. The aim of this study was to determine the oviposition preference of S. spini in calcareous grasslands, and to give management recommendations to promote this species. Therefore, we studied the oviposition microhabitats of S. spini at three representative patches of the Diemel Valley (Central Germany) by comparing environmental conditions on occupied and control host plants. In total we surveyed 1,889 host plants. Altogether we found 148 batches of S.spini on them containing 396 eggs. Most of the eggs were on plants that grew under the warmest conditions. Females preferred to lay eggs on small (< 1.3 m) shrubs of Rh. cathartica fully exposed to the sun growing on steep south- and west-facing slopes. This butterfly showed no difference in its preference for bushes growing in hedges or solitarily. About 80% of the batches of eggs were laid on the upper surface of a twig fork close to the surface of the ground (< 1 m). Our study showed that S. spini is a species characteristic of mid-successional stages of calcareous grasslands. The survival of suitable habitats for S. spini depends on regular management. To achieve this we recommend traditional rough grazing with sheep and goats, which creates open grasslands with small Rhamnus plants. In addition, the shrubs in tall hedges bordering calcareous grasslands should be subjected to cutting on a rotating basis.

Chromosomal mapping of two Mariner-like elements in the grasshopper Abracris flavolineata (Orthoptera: Acrididae) reveals enrichment in euchromatin

Octavio M. PALACIOS-GIMENEZ, Danilo BUENO, Diogo C. CABRAL-DE-MELLO

Eur. J. Entomol. 111 (3): 329-334, 2014 | DOI: 10.14411/eje.2014.052

The occurrence of transposable elements (TEs) is a ubiquitous characteristic of eukaryotic genomes, and these sequences are highly abundant in some species. Due to their large genomes, grasshoppers (Orthoptera) appear to be potentially good candidates in terms of having genomes that harbour considerable numbers of TEs. In the present study, we have investigated the occurrence of two Mariner-like elements (MLEs) within the genome of the grasshopper, Abracris flavolineata (De Geer, 1773), describing their distribution in both the A (i.e. standard or normal) complement and B chromosomes. PCR amplification followed by cloning and sequencing revealed two Mariner-like elements, which were named Afmar1 and Afmar2. Moreover, subsequent fluorescence in situ hybridization (FISH) assays indicated an abundance of these elements in the euchromatic regions of all the standard complement chromosomes and an absence of such sequences in heterochromatic regions. These sequences were also abundant in the euchromatic B chromosome: Afmar1 was distributed along the entire length of the chromosome, whereas Afmar2 was restricted to the proximal/interstitial regions of the chromosomal long arm. The general aspects of the distribution patterns of the two MLEs are discussed as well as their possible involvement in the origin and diversification of the B chromosome in A. flavolineata.

Fungi associated with the red-haired bark beetle, Hylurgus ligniperda (Coleoptera: Curculionidae) in the forest-steppe zone in eastern Ukraine

Kateryna DAVYDENKO, Rimvydas VASAITIS, Valentyna MESHKOVA, Audrius MENKIS

Eur. J. Entomol. 111 (4): 561-565, 2014 | DOI: 10.14411/eje.2014.070

The aim of this study was to investigate the composition of the fungal community associated with the red-haired bark beetle (Hylurgus ligniperda Fabricius) in two plantations of Pinus sylvestris L. located in the Kharkiv and Luhansk regions (ca. 250 km apart) in the forest-steppe zone in eastern Ukraine. In each plantation, 48 beetles were collected from butts of living trees and 48 beetles from stems of fallen trees, i.e., a total of 96. Half of the beetles from each site were used for culturing fungi and the other half for direct sequencing the internal transcribed spacer of fungal ribosomal RNA (ITS rRNA). Thirty distinct fungal taxa were identified by culturing and 31 by direct sequencing. When pooled, there were 40 fungal taxa among which Ophiostoma piceae (Münch) Sydow & P. Sydow (10.3%), Alternaria alternata (Fries) Keissler (9.7%), Ogataea neopini Nagatsuka, S. Saito & Sugiyama (8.0%), Botryotinia fuckeliana (de Bary) Whetzel (5.1%), Cladosporium sp. Link (5.1%) and Sydowia polyspora (Brefeld & Tavel) E. Müller (4.6%) were the most common. Species of the genus Ophiostoma were the most abundant and included five different taxa O. piceae, O. bicolor R.W. Davidson & D.E. Wells, O. ips (Rumbold) Nannfeldt, O. canum (Münch) Sydow & P. Sydow and O. rectangulosporium Ohtaka, Masuya & Yamaoka, all of which are known to be at most weak pathogens of trees. The plant pathogen Botryotinia fuckeliana and insect pathogens Isaria farinose (Holmskjold) Fries and Beauveria bassiana (Balsamo-Crivelli) Vuillemin were also detected. Basidiomycetes were rare, among which three wood-decaying fungi Bjerkandera adusta (Willdenow) P. Karsten, Fomitopsis pinicola (Swartz) P. Karsten and Heterobasidion annosum (Fries) Brefeld were detected. In conclusion, in the forest-steppe zone in eastern Ukraine H. ligniperda is a vector of diverse communities of fungi the majority of which, if at all, are only weak pathogens of trees.

Elytral surface structure in Poecilus lepidus (Coleoptera: Carabidae): What about the nature of its inheritance?

Dietrich MOSSAKOWSKI, Wilfried PAARMANN

Eur. J. Entomol. 111 (5): 601-607, 2014 | DOI: 10.14411/eje.2014.087

The cuticle of the ground beetle Poecilus lepidus (Leske) (Coleoptera: Carabidae) displays a complex variety of colour morphs that are genetically determined. Besides the colour of the elytra, there is a remarkable intersexual dimorphic difference in its surface structure between males and females, as there is in most Poecilus species. At least in Central European populations of P. lepidus, all males exhibit a bright elytral surface, whereas all females exhibit a matt surface; this difference is due to a nearly plain surface in males but a knobbly sculptured one in females. At first glance, this phenomenon may be easily interpreted as being a result of secondary sexual character inheritance. However, P. lepidus specimens are known from two other regions that differ markedly: females display the same bright elytral surfaces as males in the Italian Apennine Mountain and all over Bulgaria. In the present study, crossbreeding experiments with German and Bulgarian specimens resulted in a dominance of matt over bright in the classical Mendelian F2 3 : 1 ratio, although only in females. All the males showed a bright elytral surface. These findings throw into question the interpretation as given above. Because classical modes of inheritance do not provide a sound interpretation of the data as here detailed, we discuss two forms of epigenetic mechanisms which might be responsible for the observed sexual dimorphism: (1) silencing of a gene by genomic imprinting, and (2) haplo-insufficient dominance of one allele to its counterpart. Ultimately, the observed pattern is interpreted by sex-limited inheritance that depends on the presence or absence of a particular allele.

Analysis of the number of sensilla on the labrum and the diet of grasshoppers belonging to the family Pamphagidae (Orthoptera)

Naima BENKENANA, Abboud HARRAT, Daniel PETIT

Eur. J. Entomol. 110 (2): 355-364, 2013 | DOI: 10.14411/eje.2013.097

We studied the diet of 10 species of grasshopper belonging to the family Pamphagidae over a period of 3 years at 6 localities in North Eastern Algeria. The species of plants consumed by the grasshoppers was determined by comparing slide mounted specimens of the pieces of plant epidermis in their faeces with those in a reference collection of identified plants collected from the same localities. The percentages of occurrence of the different species of plants in the faeces of the grasshoppers were not related to the abundance of the plants at the sites studied. All the grasshoppers were polyphagous but differed in the percentage of Poaceae in their diets. The diet of Tmethis and Ocneridia contained a higher percentage of Poaceae than the other species and are considered to be ambivores. The three species in the Pamphagus gr. djelfensis complex differ in their diets but all tend to avoid consuming Poaceae and are categorized as forbivores. We also compared the frequency of occurrence of Fabaceae in the faeces and in the field and O. volxemii is the only species that avoided consuming this plant family. The number of sensilla on the labrum was also studied in both sexes of each species. Once one corrects for differences in the size of the labrum, the forbivores have higher numbers of sensilla in groups A1, A2 and A3 (but not A10) than the ambivores. The numbers of sensilla in the A10 group on the labrum of species of Pamphagidae is greater than on that of species of Acrididae, which are mainly graminivores and adapted to semi-arid conditions.

The long-awaited first instar larva of Paussus favieri (Coleoptera: Carabidae: Paussini)

Andrea DI GIULIO, Emanuela MAURIZI, Peter HLAVÁČ, Wendy MOORE

Eur. J. Entomol. 108 (1): 127-138, 2011 | DOI: 10.14411/eje.2011.016

Paussus favieri Fairmaire is one of only two species of the myrmecophilous carabid tribe Paussini known from Europe. Larvae are known from only 10 of the 580 paussine species. As in many beetles with considerably modified later instar larvae, the first instars represent a valuable source of informative characters for taxonomy and phylogenetic analyses (primary chaetotaxy, egg-bursters, etc.). Therefore, the discovery of the first instar larva of P. favieri is particularly important, as it represents only the second species for which this larval stage is known. In this paper we describe the behavior and morphology of the larval first instar of P. favieri (subtribe Paussina of Paussini) and compare it with that of Arthropterus sp. (subtribe Cerapterina), which is the only other 1st instar described in the Paussini. Most surprisingly, we found that the 1st instar of P. favieri lacks a prostheca, which was previously thought to be a synapomorphy of Paussina + Platyrhopalina. Rather, P. favieri has a unique mandibular structure that seems to be functionally analogous to the protheca. It is a long, broadly lanceolate, distinctly flattened structure apparently homologous to the medial mandibular seta (MN2*), which arises from an area behind the cutting edge of mandible. We predict that the function of the protheca and this similar structure in P. favieri are involved in a specialized feeding strategy that may include soliciting trophallaxis from their host ants. We also report some observations of the first instar hatching from the egg, feeding on liquid and a behaviour we interpret as a "calling behavior," all of which were videotaped and posted on the Tree of Life Web Project.

Male flies with yellow balls - New observations on the eversible vesicles on the postabdomen of male Thaumatomyia notata (Diptera: Chloropidae)

Marion KOTRBA

Eur. J. Entomol. 106 (1): 57-62, 2009 | DOI: 10.14411/eje.2009.009

The paired eversible vesicles on the postabdomen of male T. notata are likely to play an important role in intraspecific communication and possibly in the notorious aggregation behaviour of these flies at buildings in autumn. The morphological and histological study of these organs provides new evidence supporting the hypothesis that they are pheromone glands. They also constitute a strong optical signal. A detailed survey of these structures could provide the bases for targeted control methods.

Relationships between Psychidae communities (Lepidoptera: Tineoidea) and the ecological characteristics of old-growth forests in a beech dominated landscapeOriginal article

Stefano SCALERCIO, Teresa BONACCI, Rosario TURCO, Vincenzo BERNARDINI

Eur. J. Entomol. 113: 113-121, 2016 | DOI: 10.14411/eje.2016.014

Several studies address the question of which forest attributes are most important for the conservation of biodiversity. Unfortunately, there are no unequivocal answers because the response of a biological group to changes in forest structure depends on its natural history and scale of organization. It is important to increase our knowledge of the potential relationships between under studied groups of species and forest variables in order to adopt timber harvesting strategies not detrimental to biodiversity, especially in old-growth forests. We assessed the importance of 10 forest attributes and old-growth for Psychidae (Lepidoptera) species and communities. Research was carried out in 12 forest stands in a mountainous beech dominated landscape in southern Italy, in the middle of the Mediterranean Basin. Samples were collected in 2001 and 2013 and data were merged after pairwise comparison analyses that confirmed the long term stability of communities. Correspondence Analysis, Cluster Analysis and non-parametric Spearman Rank Order Correlation were used to identify determinants of Psychidae abundance and diversity. We collected 2,732 Psychidae belonging to 8 species. Correspondence analysis identified old-growth as the main determinant of communities. Most significant attributes for individual species were beech dominance, diameter at breast height and its standard deviation. For Taleporia defoliella there were positive correlations with these forest parameters, whereas for Psyche crassiorella the correlations were negative. This study underlined the importance of forest attributes associated with old-growth forests for sustaining biodiversity. These findings indicate the need to incorporate these attributes in forest planning, especially those aspects that are easily recognizable such as the number of large trees.

Implications of insect responses to supernormal visual releasing stimuli in intersexual communication and flower-visiting behaviour: A reviewReview

Karl KRAL

Eur. J. Entomol. 113: 429-437, 2016 | DOI: 10.14411/eje.2016.056

Animals, including human beings, tend to respond more strongly to stimuli that are associated with the highest relative rewards. This applies not only to food rewards but also to reproductive success. In the present review article this issue is discussed for insects in connection with intersexual communication and flower-visiting behaviour. Implications of the preference for supernormal visual releasing stimuli are examined from a sensory and evolutionary perspective, including a consideration of the choice of potential mates and recognition of the most rewarding flowers.

Silk recycling in larvae of the wax moth, Galleria mellonella (Lepidoptera: Pyralidae)Original article

Haq Abdul SHAIK, Archana MISHRA, František SEHNAL

Eur. J. Entomol. 114: 61-65, 2017 | DOI: 10.14411/eje.2017.009

Galleria mellonella larvae spin protective tubes, which they use until they finish feeding, when they spin cocoons. A feeding choice experiment showed that some of the silk produced by feeding larvae was consumed in addition to the standard diet (STD). To determine the effect of feeding on silk, last instar larvae were fed for 24 h on foods based on STD but modified by replacing the dry milk component (10% of the diet) with equal amounts of different kinds of silk. While each control larva consumed 21 ± 0.5 mg of the STD and produced 4.5 ± 0.1 mg of silk, larvae that ate the food that contained larval silk consumed 10 ± 0.4 mg of food and produced 6.1 ± 0.1 mg silk; the percentage ratio of silk produced to diet consumed was 21% and 61%, respectively. A more pronounced reduction in food consumption occurred when larvae were supplied with Galleria "cocoon" silk or the sericin fraction of such silk, and only 3.8 mg/larva was ingested of the diet containing Bombyx mori cocoon silk or its sericin fraction. Silk production expressed in terms of percentage of diet consumed was always higher than that recorded for larvae fed STD. We conclude that G. mellonella larvae recycle part of the silk that they produce during feeding. Presence of silk in the diet reduces food intake but increases the ratio of silk production to diet consumption. Sericin fraction of the cocoon silk seems to deter feeding.

Book review: Miller K.B. & Bergsten J. 2016: Diving Beetles of the World. Systematics and Biology of the Dytiscidae.Book review

Jiří HÁJEK, David S. BOUKAL

Eur. J. Entomol. 114: 332-333, 2017 | DOI: 10.14411/eje.2017.041

Miller K.B. & Bergsten J. 2016: Diving Beetles of the World. Systematics and Biology of the Dytiscidae. John Hopkins University Press, Baltimore, 320 pp. ISBN 978-1-4214-2054-7 (printed); 978-1-4214-2055-4 (electronic). Price USD 150.00.

Chromosome mapping of 28S ribosomal genes in 11 species of Cassidinae (Coleoptera: Chrysomelidae)Original article

Amália T. LOPES, Flávia R. FERNANDES, Marielle C. SCHNEIDER

Eur. J. Entomol. 114: 546-553, 2017 | DOI: 10.14411/eje.2017.069

In this study, we examined for the first time the distribution of the 28S ribosomal genes in beetles of the subfamily Cassidinae. More than 55% of the species in this subfamily have a similar karyotype, 2n = 16 + Xyp. For this work, we selected species belonging to the tribes Cassidini and Mesomphaliini, which have, respectively, the most conserved and diversified karyotype characteristics within the Cassidinae. An analysis of 11 species revealed that rDNA sites on one pair of autosomes is the most frequent pattern, occurring in 10 species. This condition occurs in the seven genera examined and in species of both of the tribes, Cassidini and Mesomphaliini. Nevertheless, the differences in the locations of 28S rDNA were more pronounced in the tribe Cassidini and among species with similar karyotype characteristics. On the other hand, in Mesomphaliini, the increase in the diploid number was not accompanied by an increase in the number of ribosomal sites. Moreover, the comparison of the number and localization of major rDNA sites with the distribution of constitutive heterochromatin indicates that there is no direct correlation between the dispersion of constitutive heterochromatin and 28S rDNA genes in Cassidinae.

Plant volatiles challenge inhibition by structural analogs of the sex pheromone in Lobesia botrana (Lepidoptera: Tortricidae)Original article

Albert SANS, Miguel MORÁN, Magí RIBA, Ángel GUERRERO, Jaume ROIG, César GEMENO

Eur. J. Entomol. 113: 579-586, 2016 | DOI: 10.14411/eje.2016.078

Plant volatiles can synergize the response to moth pheromone. Synthetic pheromone analogs, in turn, have the opposite effect in reducing pheromone attractiveness. To determine how these two types of stimuli interact and influence male moth behaviour, we performed wind tunnel experiments on the grapevine moth, Lobesia botrana. We noticed that a blend of host plant volatiles [(E)-β-caryophyllene, 1-hexanol, (Z)-3-hexenyl acetate and 1-octen-3-ol in a 100:20:10:5 ratio] significantly increased the response of males to an optimized blend of sex pheromone [(7E,9Z)-dodeca-7,9-dienyl acetate (E7,Z9-12:Ac), (7E,9Z)- dodeca-7,9-dienol (E7,Z9-12:OH) and (Z)-9-dodecenyl acetate (Z9-12:Ac)] in a 100:10:2 ratio. However, the response of males to the natural attractant was significantly reduced by two analogs [(9E,11Z)-tetradeca-9,11-dien-2-one (MK 2) and [(9E,11Z)-1,1,1-trifluoro-tetradeca-9,11-dien-2-one (TFMK 3)], of the major component of the sex pheromone of the insect (E7,Z9-12:Ac). When both stimuli were tested on males at pheromone:analog:plant volatile blend 1:100:1000 ratio, the plant blend offset the inhibitory effect induced by TFMK 3 but not that of MK 2. Our results show for the first time that under laboratory conditions plant volatiles can prevent inhibition by a pheromone analog.

Book Review: Moss B. 2017: Ponds and small lakes. Microorganisms and freshwater ecology. Naturalists' Handbooks 32.Book review

M. PAPÁČEK

Eur. J. Entomol. 114: 507, 2017 | DOI: 10.14411/eje.2017.064

Moss B. 2017: Ponds and small lakes. Microorganisms and freshwater ecology. Naturalists' Handbooks 32. Pelagic Publishing, Exeter, UK, 216 pp. ISBN 978-178427-135-0 (Pbk), 978-178427-135-7 (ePub), 978-178427-135-4 (Mobi), 978-178427-135-1 (PDF). Price GBP 19.99 (Pbk).

Co-occurrence of host plants associated with plant quality determines performance patterns of the specialist butterfly, Battus polydamas archidamas (Lepidoptera: Papilionidae: Troidini)Original article

Rodrigo S. RIOS, Cristian SALGADO-LUARTE, Gisela C. STOTZ, Ernesto GIANOLI

Eur. J. Entomol. 113: 150-157, 2016 | DOI: 10.14411/eje.2016.019

In herbivorous insects, differences in the degree of specialization to host plants emerge when the distribution of an herbivore differs from that of its host plants, which results in a mosaic of populations differing in performance on the different host plants. Using a specialized butterfly, Battus polydamas archidamas Boisduval, 1936, which feeds exclusively on the genus Aristolochia, we test whether host plant co-occurrence and associated differences in host quality modify local adaptation in terms of larval preference and performance. We compared individuals from a monospecific host stand of Aristolochia chilensis with those from a mixed host stand of A. chilensis and A. bridgesii. Individuals were reared in a reciprocal transfer experiment in which source population and the host species fed to larvae were fully crossed in a two-by-two factorial experiment in order to quantify their preference, performance (development time, size and growth rate) and survival. Individuals from both populations preferred the species they ate during their larval development over the other host, which indicates host plant-induced preference with non-adaptive implications. Larvae from mixed and monospecific stands grew faster and survived better when reared on A. bridgesii than A. chilensis. Larvae from a monospecific host stand grew slower and fewer individuals survived under the same local conditions, which is contrary to expectations. Therefore, rearing the butterfly on A. bridgesii consistently resulted in better performance, which indicates that the monospecific population is less well adapted to its host than the mixed population. Variation in the occurrence of the two host plants in the two populations can result in divergent selection due to the variation in plant quality, which in this case could result in opposing adaptive processes.

Condensella and Endogena, two new genera of the Alebroides genus group (Hemiptera: Cicadellidae: Typhlocybinae) from the Oriental Region with notes on the phylogeny of EmpoasciniOriginal article

Ye XU, Christopher H. DIETRICH, Wenhui ZHAO, Daozheng QIN

Eur. J. Entomol. 114: 462-469, 2017 | DOI: 10.14411/eje.2017.059

Two new microleafhopper genera of Empoascini within the subfamily Typhlocybinae (Hemiptera: Cicadellidae), Condensella Xu, Dietrich & Qin gen. n., based on the type species C. filamenta Xu, Dietrich & Qin sp. n., and Endogena Xu, Dietrich & Qin gen. n., based on the type species E. flava Xu, Dietrich & Qin sp. n., are described from southern China and Thailand. Male habitus photos and illustrations of male genitalia of the two new species are provided. Comparative notes on related genera are provided. Phylogenetic relationships and the status of genus groups within the tribe are also discussed.

Book review: Jäch M.A., Kodada J., Brojer M., Shepard W.D. & Čiampor F. Jr. 2016: Coleoptera: Elmidae and Protelmidae. World Catalogue of Insects, Vol. 14.Book review

David S. BOUKAL

Eur. J. Entomol. 114: 372, 2017 | DOI: 10.14411/eje.2017.047

Jäch M.A., Kodada J., Brojer M., Shepard W.D. & Čiampor F. Jr. 2016: Coleoptera: Elmidae and Protelmidae. World Catalogue of Insects, Vol. 14. Brill, Leiden / Boston, xxi + 318 pp. ISBN 978-90-04-29176-8 (hardback), 978-90-04-29177-5 (e-book). Price EUR 93.00.

Host plants and aphid hosts influence the selection behaviour of three aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae)Original article

Loulou ALBITTAR, Mohannad ISMAIL, Claude BRAGARD, Thierry HANCE

Eur. J. Entomol. 113: 516-522, 2016 | DOI: 10.14411/eje.2016.068

Aphis fabae and Myzus persicae (Hemiptera: Aphididae) are insect pests that damage sugar beet and bean crops. Both are responsible for losses in yield and transmission of viral diseases, and may be present on the same host at the same time. Three parasitoid species, Aphidius colemani, Lysiphlebus testaceipes and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae) have the potential to be used as biological control agents against at least one of these species of aphids. As a first step prior to the implementation of a biological control program, our aim was to understand the host selection behaviour of the parasitoids, particularly when both aphids are present. We recorded the host acceptance (number of insertions of the ovipositor / number of antennal contacts), suitability (number of mummies / the number of insertions of the ovipositor) and emergence (number of adults emerging from mummies) of these three aphid parasitoids when parasitizing the two aphids. We also analyzed the effect of the host plant on the host preference of the parasitoid. Females of each parasitoid species (n = 15) were exposed to 20 aphids of A. fabae or M. persicae, or a mixture of these two species of aphids, for 15 min, on a leaf disc of each of the two host plants, sugar beet and bean. Higher host acceptance and suitability were recorded for A. colemani attacking both species of aphid: A. fabae (43 and 46%) and M. persicae (43 and 46%) on beet and bean plants respectively, compared to L. testaceipes and L. fabarum. L. testaceipes and L. fabarum showed a clear preference for A. fabae. L. fabarum accepted M. persicae on both plants only when it was mixed with A. fabae, probably due to a confusion effect. We found that the host plant played a significant role in host acceptance, host suitability. We conclude that A. colemani is the better of the three parasitoids studied for the biological control in bean, and particularly, sugar beet crops.

Book Review: Löbl I. & Löbl D. (eds) 2015: Catalogue of Palaearctic Coleoptera. Hydrophiloidea-Staphylinoidea. Vol. 2. Revised and updated edition.Book review

Aleš BEZDĚK

Eur. J. Entomol. 114: 34, 2017 | DOI: 10.14411/eje.2017.005

Löbl I. & Löbl D. (eds) 2015: Catalogue of Palaearctic Coleoptera. Hydrophiloidea-Staphylinoidea. Vol. 2. Revised and updated edition. Brill, Leiden, Boston, xxvi + 1702 pp. ISBN 978-90-04-28992-5 (print book), ISBN 978-90-04-29685-5 (e-book). Price USD 245.00.

The earliest fossil flower bugs (Heteroptera: Cimicomorpha: Cimicoidea: Vetanthocoridae) from the Middle Jurassic of Inner Mongolia, China

Wenjing HOU, Yunzhi YAO, Weiting ZHANG, Dong REN

Eur. J. Entomol. 109 (2): 281-288, 2012 | DOI: 10.14411/eje.2012.036

One new genus with two new fossil species, Pumilanthocoris gracilis gen. n. sp. n. and P. obesus gen. n. sp. n., which were found in the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China, are described and illustrated. These are the earliest fossil records of Vetanthocoridae.

White plant shoots, wax-producing insects and other white structures made by arthropods: A mimicry complex?Point of view

Kazuo YAMAZAKI

Eur. J. Entomol. 114: 343-349, 2017 | DOI: 10.14411/eje.2017.043

Many insects masquerade as parts of plants, such as bark or leaves, or mimic poisonous organisms in order to defend themselves against predators. However, recent studies indicate that plants may mimic insects and other arthropods to deter herbivores. Here, I report visually similar white structures of plants and arthropods in Japan and suggest they are part of a mimicry complex. Young shoots covered with white trichomes or waxy substances may mimic wax-producing insects, such as woolly aphids, coccids and caterpillars, potentially resulting in reduced herbivory. Since wax-producing insects would reduce plant quality and quantity, be distasteful and attract natural enemies, herbivorous insects and mammals may avoid such white shoots. Furthermore, fungus-infected insects, gregarious braconid cocoons, spider egg sacs and froth made by froghopper nymphs or blasticotomid sawfly larvae are also conspicuously white and impose risks for herbivorous insects. Thus, these white structures may be mimicry models for white shoots and are likely to be part of a defensive mimicry complex. Although this study focuses on defence against herbivores, there are simultaneous physiological roles for white colouration that will not be discussed in depth here.

Protogyny after hibernation and aestivation in Cheilomenes sexmaculata (Coleoptera: Coccinellidae) in central JapanNote

Yasuko KAWAKAMI, Kazuo YAMAZAKI, Kazunori OHASHI

Eur. J. Entomol. 114: 275-278, 2017 | DOI: 10.14411/eje.2017.033

Differences in the time of occurrence of both sexes of adult ladybirds, which reflect differences in the longevity and reproductive strategies of the sexes, is important from the perspective of applied entomology, including biological control, as well as basic entomology. Nevertheless, there is little field census data on this topic. We investigated the seasonal occurrence of both sexes of Cheilomenes sexmaculata (Fabricius) in Osaka City, central Japan, from 2003 to 2011. Female adults tended to appear earlier than males after hibernation or aestivation. That males never appeared earlier than females during the nine year period of this study indicate that protogyny occurs after hibernation and aestivation in this species.

Has the currently warming climate affected populations of the mountain ringlet butterfly, Erebia epiphron (Lepidoptera: Nymphalidae), in low-elevation mountains?Original article

Martin KONVIČKA, Jiří BENEŠ, Oldřich ČÍŽEK, Tomáš KURAS, Irena KLEČKOVÁ

Eur. J. Entomol. 113: 295-301, 2016 | DOI: 10.14411/eje.2016.036

Climate change scenarios predict losses of cold-adapted species from insular locations, such as middle high mountains at temperate latitudes, where alpine habitats extend for a few hundred meters above the timberline. However, there are very few studies following the fates of such species in the currently warming climate. We compared transect monitoring data on an alpine butterfly, Erebia epiphron (Nymphalidae: Satyrinae) from summit elevations of two such alpine islands (above 1300 m) in the Jeseník Mts and Krkonoše Mts, Czech Republic. We asked if population density, relative total population abundance and phenology recorded in the late 1990s (past) differs that recorded early in 2010s (present) and if the patterns are consistent in the two areas, which are separated by 150 km. We found that butterfly numbers recorded per transect walk decreased between the past and the present, but relative population abundances remained unchanged. This contradictory observation is due to an extension in the adult flight period, which currently begins ca 10 days earlier and lasts for longer, resulting in the same total abundances with less prominent peaks in abundance. We interpret this development as desynchronization of annual cohort development, which might be caused by milder winters with less predictable snow cover and more variable timing of larval diapause termination. Although both the Jeseník and Krkonoše populations of E. epiphron are abundant enough to withstand such desynchronization, decreased synchronicity of annual cohort development may be detrimental for innumerable small populations of relic species in mountains across the globe.

Phenological responses of Pseudomallada (Neuroptera: Chrysopidae): Comparative data from three Nearctic species and interspecific hybrids

Maurice J. TAUBER, Catherine A. TAUBER

Eur. J. Entomol. 112 (1): 49-62, 2015 | DOI: 10.14411/eje.2015.015

Three Nearctic species - Pseudomallada macleodi (Adams & Garland), P. perfectus (Banks), and P. sierra (Banks) - share a suite of phenological characteristics with their Western Palearctic congeners. They overwinter as free-living larvae (primarily third instars) in a photoperiodically induced diapause. For these three species, the critical photoperiods for diapause induction fell between LD 16:8 and LD 14:10. In the laboratory, larvae remained responsive to daylength throughout diapause - short daylengths maintained diapause until diapause terminated spontaneously or death occurred. Transfer of diapausing larvae from short to intermediate or longer days accelerated diapause development, apparently in a quantitative response to daylength. A period of chilling appeared to delay, rather than hasten, diapause development. In general, the expression of diapause in F1 hybrids (P. perfectus × P. sierra) resembled that of the parents; there were minor differences in some features. Among populations of the three species under non-diapause conditions, the times for complete development (egg hatch to adult emergence) ranged between 40 and 50 days (23.9°C). Under long-day conditions, developmental rates of the P. perfectus egg and prepupal-pupal stages were linearly related to temperature; we provide thermal thresholds and heat-degree days for these stages. In contrast, developmental rates of free-living larvae did not have a linear relationship with temperature; photoperiod may interact with temperature to affect non-diapause development in these stages.

Climate-induced changes in the phenotypic plasticity of the Heath Fritillary, Melitaea athalia (Lepidoptera: Nymphalidae)Original article

Edit JUHÁSZ, Zsolt VÉGVÁRI, János P. TÓTH, Katalin PECSENYE, Zoltán VARGA

Eur. J. Entomol. 113: 104-112, 2016 | DOI: 10.14411/eje.2016.013

Recently a large number of studies have reported an increase in the variability in the climate, which affects behavioural and physiological adaptations in a broad range of organisms. Specifically, insects may be especially sensitive to climatic fluctuations, as their physiology and life history traits, like those of other ectotherms, are predominantly affected by environmental factors. Here we aimed to investigate climate-induced changes in several morphometric measures of the Heath Fritillary in North-Eastern Hungary, which is a highly diverse transitional area. During this study we tested the following hypotheses: (i) climate affects genitalia and body size to various degrees (ii) increasing variability in climate induces higher levels of fluctuating asymmetry and variance in all morphological characters. To our knowledge, this study is the first to analyse simultaneously wing size and structure of genitalia of a butterfly in response to variability in climate. Our findings suggest that wing and genital traits may exhibit similar degrees of stability in response to a more variable climate, although the response in terms of forewing size differs from that of other body measurements and the structure of the genitalia. These findings suggest that global climate change may affect lepidopteran body metrics over longer periods of time. Our findings parallel the results of investigations showing that insect morphology might be modified by environmental changes, which is especially the case for those body parts that are phenotypically very variable. However, we found no evidence that increasing variability in climate would induce higher levels of fluctuating asymmetry and greater variability in morphological characters.

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