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Coniophloeus, a new genus of Embrithini from South Africa, with description of four new species (Coleoptera: Curculionidae: Entiminae)Original articleRoman BOROVECEur. J. Entomol. 116: 201-211, 2019 | DOI: 10.14411/eje.2019.022 A new genus, Coniophloeus gen. n., is described for five species of South African weevils known from the Western and Eastern Cape and assigned to the tribe Embrithini Marshall, 1942: Coniophloeus squalidus (Boheman, 1842) comb. n. (type species, transferred from the genus Trachyphloeus Germar, 1817 and tribe Trachyphloeini Lacordaire, 1863), C. alternans sp. n., C. oberprieleri sp. n., C. robustus sp. n. and C. obrieni sp. n. All five species are illustrated and keyed. |
Preference of two populations of Propylea quatuordecimpunctata (Coleoptera: Coccinellidae) for Aphis fabae and Aphis gossypii (Homoptera: Aphididae)Maryam KESHAVARZ, Marjan SEIEDY, Hossein ALLAHYARIEur. J. Entomol. 112 (3): 560-563, 2015 | DOI: 10.14411/eje.2015.065 Prey preference of natural enemies is an important parameter used in studies on their efficiency. Feeding preferences of individuals from two populations of Propylea quatuordecimpunctata (L.) (Coleoptera: Coccinellidae) for the essential prey items, Aphis fabae Scopoli, 1763 and Aphis gossypii Glover, 1877 (Homoptera: Aphididae) were evaluated in the laboratory using Manly's β preference index (β). For the predator preference experiment, equal numbers of A. fabae and A. gossypii were offered to the predator. The experiment was conducted on a broad bean leaf disc with 20 replicates. After 24 h, the unconsumed aphids were counted. Individuals of P. quatuordecimpunctata from both populations consumed more A. gossypii [Karaj population (mean ± SE): 28.15 ± 1.04 and Sari population 34.35 ± 0.51] than A. fabae (Karaj population: 17.95 ± 0.64 and Sari population: 17.7 ± 1.01). The values of Manly's β preference index (β) for A. gossypii were 0.73 ± 0.01 and 0.77 ± 0.01 for the Karaj and Sari populations, respectively and for A. fabae were 0.26 ± 0.01 and 0.22 ± 0.01 for the Karaj and Sari populations, respectively. Comparison of the preference indices using a t-test revealed significant differences between the prey preferences of those from the Sari population (t = 22.53, df = 38, P < 0.0001) and the Karaj population (t = 26, df = 38, P < 0.0001). These results reveal that P. quatuordecimpunctata from the two populations prefer A. gossypii over A. fabae. |
Rearing of Microplitis mediator (Hymenoptera: Braconidae) and its host Mamestra brassicae (Lepidoptera: Noctuidae)Elodie BELZ, Céline E. GÉNEAU, Moritz FÜRST, Oliver BALMER, Pius ANDERMATT, Lukas PFIFFNER, Léon WESTERD, Henryk LUKAEur. J. Entomol. 111 (3): 443-447, 2014 | DOI: 10.14411/eje.2014.043 Establishing continuous and reliable colonies of pest-parasitoid systems in the laboratory is an essential requirement for carrying out manipulative experiments on biological control. Here we describe in detail the rearing protocols that we optimized for the efficient rearing of the cabbage moth Mamestra brassicae and its key parasitoid Microplitis mediator. |
Development and thermal requirements of the Nearctic predator Geocoris punctipes (Hemiptera: Geocoridae) reared at constant and alternating temperatures and fed on Anagasta kuehniella (Lepidoptera: Pyralidae) eggsAna M. CALIXTO, Vanda H.P. BUENO, Flávio C. MONTES, Joop C. VAN LENTERENEur. J. Entomol. 111 (4): 521, 2014 | DOI: 10.14411/eje.2014.074 Knowledge of the optimal temperatures for development and survival of biological control agents is essential for efficient mass-rearing and introduction of natural enemies in augmentative biological control programs. We studied the effect of constant and alternating temperatures on development and survival of immature stages and the sex ratio at emergence of adults of the Nearctic generalist predator Geocoris punctipes (Say). We also determined its thermal requirements. They were reared in climatic chambers at alternating (21/11°C, 24/18°C, 27/21°C and 30/26°C ± 1°C) and constant temperatures (16.8°C, 21.5°C, 24.5°C and 28.3°C ± 1°C), RH 70 ± 10% and a 14 h photophase. Survival and development of G. punctipes were the same when reared at constant and alternating temperatures. Five instars were recorded in all temperature regimes. The duration of the egg stage and each instar, as well as that of total larval development were longer, and larval survival lower when reared at 16.8°C, 21/11°C, 21.5°C and 24/18°C than at 24.5°C, 27/21°C, 28.3°C and 30/26°C. The optimal temperature range for development and survival of G. punctipes is 24.5°C to 30°C, its lower development threshold temperature is 13.5°C and its thermal constant 295.9 DD. Sex ratios were not significantly different from 1 : 1 male : female ratio in all temperature regimes. There is an excellent match between the temperature regimes at which the prey Tuta absoluta (Meyrick) and predator G. punctipes are active, which indicates that this predator will function well in crops where this pest is present. |
Changes in carabid beetle fauna (Coleoptera: Carabidae) along successional gradients in post-industrial areas in Central PolandAxel SCHWERKEur. J. Entomol. 111 (5): 677-685, 2014 | DOI: 10.14411/eje.2014.076 An inventory of the carabid fauna was carried out in two post-industrial areas in central Poland. The two areas studied were a heap of ash generated by a power station and a colliery spoil heap. In each area sites of different ages were investigated using pitfall traps over an eight year period from 2004 to 2011. At the end of this period each of the youngest sites was as old, or even older, than the next oldest site studied in each area. A pine forest growing on natural soil close to the ash heap was included as a reference study site. Changes were described in terms of the numbers of species and individuals, total biomass, Mean Individual Biomass of Carabidae (MIB) and the most frequently collected species. Indirect and direct gradient analyses were carried out in order to determine the environmental basis of the major pattern in variation and analyse the relationships with current environmental parameters. During the eight years of this study 5032 individuals of 84 species were collected. Numbers of individuals decreased significantly with the age of the sites on the ash heap and the MIB values increased significantly on both heaps. Changes in the most frequently collected species were more pronounced on the spoil heap, the study sites on which covered a time span of 26 years, than on the ash heap, for which the period was only 11 years. Characteristic species differed on the spoil and ash heaps and numbers of species were lower on the spoil heap. Despite differences in speed of succession at the sites studied, there was a tendency for the MIB to increase after about 9 to 16 years. Indirect and direct gradients analyses confirmed that the stage of succession (age of the study sites) was an important factor determining the carabid assemblages at the sites studied. The results of this study are important for the restoration and management of post-industrial areas. |
First chromosomal study of Mantophasmatodea: Karyotype of Karoophasma biedouwense (Austrophasmatidae)Dorota LACHOWSKA-CIERLIK, Anna MARYAÑSKA-NADACHOWSKA, Valentina KUZNETSOVA, Mike PICKEREur. J. Entomol. 112 (4): 599-605, 2015 | DOI: 10.14411/eje.2015.093 We have investigated for the first time the chromosomes of Karoophasma biedouwense, a species belonging to the Mantophasmatodea, a recently discovered order of carnivorous insects. Our study has revealed that males of this species display testes with numerous seminal tubes (follicles), as in other Polyneoptera, and short tubular seminal vesicles embedded in a utricular gland. The karyotype consists of 2n = 12A + X monocentric and biarmed, meta/submetacentric chromosomes (fundamental number of arms: FN = 26) with blocks of heterochromatin around centromeres. The autosomes are classified into two size groups, one represented by a single, very large pair of autosomes, the other by five smaller pairs which constitute a continuous series gradually decreasing in size. Among "monocentric" orders of Polyneoptera, K. biedouwense shares its low chromosome number, 2n = 13, as also found with some Orthoptera (Acridoidea, Grylloidea, Gryllacridoidea). Male meiosis is of the classical pre-reductional type and the X(0) sex determination system is probably an ancestral state. Use of FISH along with an 18S rDNA probe revealed multiple ribosomal clusters, which most likely represent an apomorphic condition. We identified the ancestral insect telomeric sequence (TTAGG)n in the terminal areas of the chromosomes. Currently available data on the polyneopteran orders putatively related to Mantophasmatodea showed a wide variability of cytogenetic characteristics within and between them. The only character allowing some tentative inference to be made on the ancestry of K. biedouwense is its low chromosome number, the karyotypic pattern so far unreported for the Polyneoptera except in certain Orthoptera. |
Bactrocera oleae (Diptera: Tephritidae) organophosphate resistance alleles in Iberia: Recent expansion and variable frequenciesIsabel PEREIRA-CASTRO, Barbara VAN ASCH, Fernando TRINDADE REI, Luís TEIXEIRA DA COSTAEur. J. Entomol. 112 (1): 20-26, 2015 | DOI: 10.14411/eje.2015.019 The olive fly, Bactrocera oleae (Rossi, 1790) (Diptera: Tephritidae), is the most important pest of olive trees globally, causing losses that, in the absence of control measures, can exceed 90% of the crop. In the Mediterranean basin, where the overwhelming majority of production is concentrated (~ 98%), organophosphate insecticides (OPs) have been the main tool for B. oleae control for the last four decades, leading to the development of resistance to these compounds. Mutations of the Ace gene, which codes for acetylcholinesterase, the target enzyme of OPs and other insecticides, have been identified as the underlying cause, with studies reporting mid to very high frequencies of resistance alleles in several countries. Interestingly, no resistance alleles were detected in Portugal, at the Western end of the Mediterranean basin. As the original study was done almost a decade ago and did not include many samples, we decided to re-evaluate the situation, by analysing a larger number of individuals from multiple locations in Western and Southern Iberia (Portugal and Spain). In our present study, resistance-associated Ace alleles were found to have become widespread in both regions, but with highly varying frequencies. Together with the observed haplotype distributions, this finding is consistent with previous suggestions of a recent, selection-driven spread and has implications for the importance of Ace mutations in organophosphate resistance in the field as well as the importance of gene flow between Mediterranean populations of B. oleae. |
Characterization of 16 novel microsatellite loci for Ephippiger diurnus (Orthoptera: Tettigoniidae) using pyrosequencing technology and cross-species amplificationNoteYareli ESQUER-GARRIGOS, Michael D. GREENFIELD, Virginie PARTY, Réjane STREIFFEur. J. Entomol. 113: 302-306, 2016 | DOI: 10.14411/eje.2016.037 A novel panel of 16 microsatellite markers, obtained by pyrosequencing of enriched genomic libraries, is reported for the flightless European bushcricket Ephippiger diurnus (Dufour) (Orthoptera: Tettigoniidae). Five multiplex and one simplex PCR protocols were optimized, and the polymorphism at the 16 loci was assessed in two natural populations from southern France. The mean allele number and (expected mean heterozygosity) were 8.94 (0.71) and 6.57 (0.70), respectively, in each population. Several loci were at Hardy-Weinberg disequilibrium (HWD), possibly due to the incidence of null alleles. The occurrence of null alleles has been previously reported for this species, and it is a common feature of microsatellite loci in Orthoptera. Cross-amplification tests demonstrated the transferability of some of these loci to other ephippigerine species. The microsatellite loci reported here substantially increase the number of available loci for this species and will afford an accurate picture of E. diurnus phylogeography, the genetic structure of its populations, and an improved understanding of the evolution of male song and other sexually-selected traits in this highly variable species. |
Sexual dimorphism in the Drosophila melanogaster (Diptera: Drosophilidae) metabolome increases throughout developmentOriginal articleFiona C. INGLEBY, Edward H. MORROWEur. J. Entomol. 114: 249-256, 2017 | DOI: 10.14411/eje.2017.030 The expression of sexually dimorphic phenotypes from a shared genome between males and females is a longstanding puzzle in evolutionary biology. Increasingly, research has made use of transcriptomic technology to examine the molecular basis of sexual dimorphism through gene expression studies, but even this level of detail misses the metabolic processes that ultimately link gene expression with the whole organism phenotype. We use metabolic profiling in Drosophila melanogaster to complete this missing step, with a view to examining variation in male and female metabolic profiles, or metabolomes, throughout development. We show that the metabolome varies considerably throughout larval, pupal and adult stages. We also find significant sexual dimorphism in the metabolome, although only in pupae and adults, and the extent of dimorphism increases throughout development. We compare this to transcriptomic data from the same population and find that the general pattern of increasing sex differences throughout development is mirrored in RNA expression. We discuss our results in terms of the usefulness of metabolic profiling in linking genotype and phenotype to more fully understand the basis of sexually dimorphic phenotypes. |
Assessing genetic and morphological variation in populations of Eastern European Lucilia sericata (Diptera: Calliphoridae)Original articleAnna V. DIAKOVA, Dmitry M. SCHEPETOV, Nadezhda Y. OYUN, Anatole I. SHATALKIN, Tatiana V. GALINSKAYAEur. J. Entomol. 115: 192-197, 2018 | DOI: 10.14411/eje.2018.017 The population structures of different species of Calliphoridae flies are highly diverse at different locations. We investigated populations of the Eastern European L. sericata using chaetotaxy and eight microsatellite loci. Our results strongly indicate that a panmictic population of L. sericata exists in the area studied, possibly with a high rate of intra-population gene flow. Analysis of chaetotaxy also supports the panmictic population hypothesis. |
Stones on the ground in olive groves promote the presence of spiders (Araneae)Original articleJacinto BENHADI-MARÍN, José A. PEREIRA, José A. BARRIENTOS, José P. SOUSA, Sónia A.P. SANTOSEur. J. Entomol. 115: 372-379, 2018 | DOI: 10.14411/eje.2018.037 Spiders are generalist predators that contribute to the control of pests in agroecosystems. Land use management determines habitats including refuges for hibernation and aestivation. The availability of shelters on the ground can be crucial for maintaining populations of spider within crops. We studied the effect of the number of stones on the surface of the soil on the spider community in selected olive groves in Trás-os-Montes (northeastern Portugal). The number of stones significantly influenced the overall diversity of spiders, abundance of immature individuals and abundance of ground hunters. Agricultural management practices aimed at the conservation of soil microhabitats such as hedgerows, stonewalls and stones on the ground should be promoted in order to maintain or increase the number of shelters for potential natural enemies of pests. |
Susceptibility of Chironomus plumosus larvae (Diptera: Chironomidae) to entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae): Potential for controlOriginal articleCassandra V. EDMUNDS, Craig S. WILDING, Robbie RAEEur. J. Entomol. 114: 526-532, 2017 | DOI: 10.14411/eje.2017.067 Chironomidae, or non-biting midges, are found worldwide in a wide variety of aquatic habitats. During periods of mass adult eclosion they can become a nuisance and health hazard. Current control methods target the aquatic larval stage and include the use of insect growth regulators or insecticides, which may be prohibited in certain environments or affect non-target organisms. The aim of this study was to investigate whether entomopathogenic nematodes (EPNs) of the families Steinernematidae and Heterorhabditidae, currently employed for control of terrestrial crop pests, could be used as a viable biocontrol for the aquatic larval stages of the Chrionomidae, offering an alternative to current chemical methods. We demonstrate that Steinernema feltiae (Filipjev, 1934), Steinernema carpocapsae (Weiser, 1955), Steinernema kraussei (Steiner, 1923) and Heterorhabditis bacteriophora (Poinar, 1975) are able to survive in water up to 96 h and are able to parasitize and kill Chironomus plumosus (Linnaeus, 1758) larvae, with mortality observed after just 24 h exposure and with < 20% survival after 4 days. We also show that following application to the water column, EPNs sink to the bottom of the lentic water body and can remain alive for more than 96 h. Taken together, we believe that several EPN species could be developed as a valid form of biocontrol for Chironomidae. |
Fine structure of the external sheaths of the ovipositor of Aphidius ervi (Hymenoptera: Braconidae)Original articleSara RUSCHIONI, Paola RIOLO, Roberto ROMANI, Donatella BATTAGLIA, Nunzio ISIDOROEur. J. Entomol. 115: 296-302, 2018 | DOI: 10.14411/eje.2018.028 The function and structure of the ovipositor in Hymenoptera have been studied intensively, although there is a lack of information on the external sheaths. We provide here a contribution on the structure of the external sheaths of the ovipositor of the parasitic wasp Aphidius ervi, in particular the secretory structure is described for the first time. These glands are made up of a large epithelial structure that consists a single layer of large secretory cells that occupy most of the lumen of the valve and belong to gland cell class 1. Based on the different features of the glands, a lubricating and/or host marking function is hypothesized and discussed. |
A comparison of methods for sampling aquatic insects (Heteroptera and Coleoptera) of different body sizes, in different habitats using different baitsOriginal articleNata¹a TURIÆ, Martina TEMUNOVIÆ, Goran VIGNJEVIÆ, Jasenka ANTUNOVIÆ DUNIÆ, Enrih MERDIÆEur. J. Entomol. 114: 123-132, 2017 | DOI: 10.14411/eje.2017.017 Although various methods exist for sampling aquatic Heteroptera and Coleoptera in standing water, there are very few comparisons of their performance in different types of habitat. In this study, we evaluated and compared the efficiency and selectivity of three sampling methods: hand netting, bottle traps baited with canned tuna and bottle traps baited with canned cat food. The methods were compared over the period 2010-2012 in two different habitats (temporarily flooded areas and canals) in the Nature Park Kopaèki rit, a floodplain on the banks of the River Danube. The results show that the effectiveness of the method differed in the two habitats. Overall, hand netting was the most successful method, mainly in canals. Tuna fish bait was more efficient than the commonly used cat food, especially for large and highly mobile species of Dytiscidae. These findings indicate that knowing the type of habitat and the habitat preferences of aquatic insects and their activity it is possible to predict which of these methods are the best for estimating species richness. |
More complex than expected: Cold hardiness and the concentration of cryoprotectants in overwintering larvae of five Erebia butterflies (Lepidoptera: Nymphalidae)Original articlePavel VRBA, Oldøich NEDVÌD, Helena ZAHRADNÍÈKOVÁ, Martin KONVIÈKAEur. J. Entomol. 114: 470-480, 2017 | DOI: 10.14411/eje.2017.060 Understanding the factors restricting the distribution of some insect species to high altitudes is hindered by poor knowledge of temporal changes in their cold hardiness during overwintering. We studied overwintering larvae of five species of Erebia butterflies (Lepidoptera: Nymphalidae: Satyrinae) differing in altitudinal distribution: lowland E. medusa, submountain E. aethiops, subalpine E. pronoe, alpine E. cassioides, and subnivean E. pluto. We subjected them to three treatments, AutumnWarm (13/8°C), imitating conditions prior to overwintering; AutumnCold (5/0°C), imitating late autumn conditions; and WinterCold (5/0°C), differing from AutumnCold by a shorter photoperiod and longer exposure to zero temperatures. Supercooling points (SCP) did not differ between species in the AutumnWarm treatment, despite large differences in the concentrations of cryoprotectants (CrPC; lowest in E. medusa and E. aethiops). Lowland E. medusa was freeze-tolerant, the subalpine, alpine and subnivean species were freeze-avoidant, whereas submountain E. aethiops displayed a mixed strategy. SCPs diverged in the AutumnCold treatment: it increased in the lowland E. medusa (from -16.5 to -10.8°C) and reached the lowest value in E. cassioides (-21.7°C). In WinterCold, SCP increased in subalpine E. pronoe (from -16.1°C in AutumnWarm and -18.7°C in AutumnCold to -12.6°C). E. medusa decreased and E. aethiops increased their CrPCs between autumn and winter; the highest CrPC was recorded in subnivean E. pluto. CrPC did not correlate with SCP across species and treatments. Cryoprotectant profiles corroborated the difference between lowland and freeze-tolerant E. medusa and the three high altitude freeze-avoidant species, with E. aethiops in an intermediate position. Glycerol was surprisingly rare, trehalose was important in all species, and such rare compounds as monopalmitin and monostearin were abundantly present in E. pronoe, E. cassioides and E. pluto. |
Host-plant leaf-surface preferences of young caterpillars of three species of Pieris (Lepidoptera: Pieridae) and its effect on parasitism by the gregarious parasitoid Cotesia glomerata (Hymenoptera: Braconidae)Original articleTomoko WATANABE, Keiji NAKAMURA, Jun TAGAWAEur. J. Entomol. 115: 25-29, 2018 | DOI: 10.14411/eje.2018.004 Preferences of young caterpillars of three species of Pieris (P. rapae crucivora Boisduval, P. melete Ménétriès, and P. napi japonica Shirôzu) (Lepidoptera: Pieridae) for the upper and lower surfaces of the leaves of their host plants (Brassicaceae) were investigated in the laboratory. On horseradish Armoracia rusticana Gaertn. Mey. et Scherb., which was provided as a common food for three species, second and third instar larvae of the respective species preferred the lower to the upper surface of horizontally placed leaves, irrespective of whether they hatched on the upper or lower surface. First instar larvae seemed to remain on the surface on which they hatched. However, first instar larvae of P. melete on Rorippa indica (L.), a natural food of P. melete in the field, and first instar larvae of P. napi japonica on Arabis flagellosa Miq., a natural food of P. napi japonica, preferred the lower to the upper surface, just as second and third instar larvae did. To elucidate the effects of leaf-surface preference, the percentage parasitism of P. rapae crucivora on Arm. rusticana and Ara. flagellosa by the parasitoid Cotesia glomerata (L.) (Hymenoptera: Braconidae) was investigated. On Arm. rusticana, the percentage parasitism of the larvae on the upper surface was higher than that of larvae on the lower surface. On Ara. flagellosa, however, percentages parasitism were nearly equal on both surfaces. Leaf-surface preference by the larvae of Pieris is discussed in terms of avoidance of parasitism by the parasitoid C. glomerata. |
First mitogenome for the tribe Saccharosydnini (Hemiptera: Delphacidae: Delphacinae) and the phylogeny of three predominant rice planthoppersOriginal articleYi-Xin HUANG, Dao-Zheng QINEur. J. Entomol. 115: 242, 2018 | DOI: 10.14411/eje.2018.023 The mitochondrial genome of Saccharosydne procerus (Matsumura) is the first sequenced in the tribe Saccharosydnini (Hemiptera: Delphacidae: Delphacinae). In addition, the mitogenome sequence of Sogatella vibix (Haupt) (in Delphacini) is also sequenced. The Sa. procerus mitochondrial genome is 16,031 bp (GenBank accession no. MG515237) in length, and So. vibix is 16,554 bp (GenBank accession no. MG515238). The existence of purifying selection was indicated by the rate of nonsynonymous and synonymous substitutions. Three species of Delphacini, Laodelphax striatellus (Fallén), Sogatella furcifera (Horváth) and Nilaparvata lugens (Stål), are important pests of rice. The phylogeny of these three rice planthoppers based on the mitochondrial genome sequence was (L. striatellus + (So. vibix + So. furcifera)) + (N. muiri + N. lugens). |
Random or clumped: How litter dwelling scorpions are distributed in a fragment of Brazilian Atlantic forestNoteGabriela Cavalcanti Silva de Gusmão SANTOS, Welton DIONISIO-DA-SILVA, João Pedro SOUZA-ALVES, Cleide Maria Ribeiro de ALBUQUERQUE, André Felipe de Araujo LIRAEur. J. Entomol. 115: 445-449, 2018 | DOI: 10.14411/eje.2018.045 Knowledge of the patterns in the spatial distribution of species provides valuable information about the factors (resources and environment) that regulate the use of space by animals. Typically, the distribution of litter-dwelling scorpions in Atlantic forests is correlated with the structure of their microhabitats, although to better understand their natural history more studies on the patterns in their use of space are required. Therefore, we investigated the effect of rainfall on the patterns in the spatial distributions and population densities of two sympatric species of scorpion, Tityus (Archaeotityus) pusillus Pocock 1893 and Ananteris mauryi Lourenço 1982 in a fragment of Atlantic Forest in Brazil. The study was carried out during the dry (September) and rainy (June) months. We collected 501 individuals (268 T. (A.) pusillus and 233 A. mauryi) by actively searching at night using UV lanterns. We found that the spatial distribution and population density of T. (A.) pusillus, but not A. mauryi, were significantly affected by rainfall, with T. (A.) pusillus individuals showing a clumped pattern during the rainy month and random distribution in the dry month. We also found a different response in the population densities of the two species, with T. (A.) pusillus but not A. mauryi being affected by rainfall. Our results indicate that, although co-habiting in leaf litter, these species respond differently to rainfall, which affects their spatial distribution and abundance in this habitat. |
Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)Original articleThomas N. PRICE, Aoife LEONARD, Lesley T. LANCASTEREur. J. Entomol. 114: 257-266, 2017 | DOI: 10.14411/eje.2017.031 Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests. |
Identification and characterization of doublesex from the pumpkin fruit fly, Bactrocera tau (Diptera: Tephritidae)Original articleThanaset THONGSAIKLAING, Hataichanok PASSARA, Mingkwan NIPITWATHANAPHON, Lertluk NGERNSIRIEur. J. Entomol. 115: 602-613, 2018 | DOI: 10.14411/eje.2018.057 The sex determination cascades in insects are diversified at the top of the cascade, where different primary molecular signals are employed, while at the bottom of the cascades, particularly the doublesex genes, are highly conserved. Here, we identified the doublesex ortholog (Btau-dsx) of Bactrocera tau, a pumpkin fruit fly, and found that Btau-dsx is composed of six exons and five introns with an additional short "m" exon located in the second intron. Btau-dsx is different from its orthologs in most dipteran insects: Its pre-mRNA is sex-specifically spliced to yield three (two male and one female) instead of two transcript variants. The two deduced proteins produced by the male-specific transcripts are a functional (Btau-DSXM1) and a truncated (Btau-DSXM2) protein, while the female-specific transcript produces the functional Btau-DSXF protein. These three proteins contain all conserved domains except Btau-DSXM2 which has no OD2 domain. The female-specific transcript is detected in both fertilized and unfertilized eggs and in both somatic and germ cells of the adult females, while the male-specific transcript is detected only in fertilized eggs and in the abdominal tissues and testes of adult males. The presence of the Btau-dsxM1 transcript in fertilized eggs at the early syncytium stage suggests that in XY embryos, the Y-linked M factor gene may function quite soon after fertilization to alter the splicing pattern of Btau-dsx pre-mRNA from the female-specific to the male-specific mode. Injection of Btau-dsxF dsRNA into recently emerging females can reduce the expression of vitellogenin (Btau-Vg) and causes some defects in the ovaries, indicating that Btau-dsxF works upstream of Btau-Vg. |
A case study of Heleomyzidae (Diptera) recorded on snow in Poland with a review of their winter activity in EuropeOriginal articleAgnieszka SOSZYÑSKA-MAJ, Andrzej J. WO¬NICAEur. J. Entomol. 113: 279-294, 2016 | DOI: 10.14411/eje.2016.035 Twenty eight species of winter-active Heleomyzidae were collected during a long-term study in Poland. More than 130 samples of insects, including Heleomyzidae, were collected from the surface of snow in lowland and mountain areas using a semi-quantitative method. Lowland and mountain assemblages of Heleomyzidae recorded on snow were quite different. Heleomyza modesta (Meigen, 1835) and Scoliocentra (Leriola) brachypterna (Loew, 1873) dominated in the mountains, Tephrochlamys rufiventris (Meigen, 1830) mainly in the lowlands and Heteromyza rotundicornis (Zetterstedt, 1846) was common in both habitats. Heleomyzidae were found on snow during the whole period of snow cover, but the catches peaked from late November to the beginning of February. In late winter and early spring the occurrence of heleomyzids on snow decreased. Most individuals were active on snow at air temperatures between -2 and +2.5°C. A checklist of 78 winter active European Heleomyzidae is presented. Helomyza nivalis Wahlgren, 1918 is herein considered as a new junior synonym of Helomyza caesia Meigen, 1830, syn. n. |
Associations between canopy openness, butterfly resources, butterfly richness and abundance along forest trails in planted and natural forestsOriginal articleAtsushi OHWAKI, Saki MAEDA, Masahiko KITAHARA, Takashi NAKANOEur. J. Entomol. 114: 533-545, 2017 | DOI: 10.14411/eje.2017.068 Increasing the biodiversity in plantations of trees is an important issue because plantations have replaced many natural and semi-natural ecosystems worldwide. Therefore, identifying appropriate management techniques and key factors for enhancing biodiversity in plantations is required. We surveyed butterfly assemblages along forest trails in both plantations and natural forests and measured various environmental variables, including canopy, sub canopy and shrub stem densities, percentage of deciduous trees, flower plant richness, host plant richness, canopy openness and distance to forest edge. We hypothesized that (1) flower and host plant richness increase with an increase in the percentage of deciduous trees and canopy openness; (2) butterfly richness and abundance increase with an increase in forest structural complexity, butterfly resources, canopy openness and distance to forest edge; (3) the responses of plants and butterflies to canopy openness differ in plantations and natural forests; and (4) in plantations, tree-feeding butterflies respond to canopy openness less strongly than herbaceous plant feeding butterflies do because of the low diversity of trees in plantations. Our results generally support these hypotheses. Butterfly resources and butterfly richness and abundance all increase with increasing canopy openness; however, the increases were usually more dramatic in natural forests than in plantations and other factors are less important. In plantations, herbaceous plant feeding butterflies responded to increasing canopy openness more strongly than tree-feeding butterflies. The results of the present study indicate the importance of sunlit forest trails in enhancing butterfly resources, butterfly richness and abundance in plantations. Because at the stand-level management is labour- and cost-intensive, labour- and cost-saving trail management options need to be explored further in terms their effectiveness in increasing biodiversity in plantations. |
Influence of urbanisation and plants on the diversity and abundance of aphids and their ladybird and hoverfly predators in domestic gardensOriginal articleElise A. ROCHA, Estevão N.F. SOUZA, Lewis A.D. BLEAKLEY, Christopher BURLEY, Jade L. MOTT, Gloria RUE-GLUTTING, Mark D.E. FELLOWESEur. J. Entomol. 115: 140-149, 2018 | DOI: 10.14411/eje.2018.013 Urban gardens can harbour a high diversity of insects, which are critically important components of urban ecosystems. In this work, we investigate the richness and diversity of a major taxon of economic and ecological importance, the aphids (Hemiptera: Aphididae), and their main insect predators, the hoverflies (Diptera: Syrphidae) and ladybirds (Coleoptera: Coccinellidae), in urban gardens. We examined how variation in environmental factors associated with urbanisation (garden host plant abundance, garden plant richness, garden size, proportion of impervious surfaces in the surrounding area) directly and indirectly (via prey and predator abundance) influence the local diversity and abundance of aphids, ladybirds, and hoverflies. Sixty-seven domestic gardens located in southern England were surveyed during the peak period of aphid abundance, and the numbers and identity of aphids and their predators were recorded. We observed 45 aphid species (179917 individuals in total), 15 hoverfly species (494 individuals) and 8 ladybird species (173 individuals). We found that aphid species richness and abundance were positively associated with utilised host plant abundance and garden plant species richness. Hoverfly abundance was positively correlated with garden plant richness. The abundance of ladybirds was positively correlated with aphid abundance and garden plant species richness, and negatively associated to the proportion of impervious surfaces in the surrounding environment. The difference in responses between the two major taxa of aphid predators may reflect differences in their behaviour and natural history. Our results indicate that overall increases in urban land cover are not favourable for ladybirds as a group, and that fine scale habitat variables that are determined by garden owners have the potential to greatly affect the diversity of aphids and their primary predators. |
A three year study of the phenology of insect larvae (Coleoptera, Diptera) in water-filled tree holes in the canopy of a beech treeOriginal articleMartin M. GOSSNEREur. J. Entomol. 115: 524-534, 2018 | DOI: 10.14411/eje.2018.052 Water-filled tree holes are abundant microhabitats in forests worldwide and are inhabited by specialized communities of invertebrates. Despite their importance, the temporal dynamics of communities within and between years are largely unknown. Here, I present a case study on the phenology of insect larvae in two holes in a beech tree (lower and upper canopy) located in southern Germany over a period of three years. I asked whether water temperature and the characteristics of insect larvae at the community and population levels are similar in periodicity every year and whether they differ in the lower and upper canopy. The water temperature in tree holes differed greatly from air temperature, and this effect was more pronounced in the lower than in the upper canopy, which resulted in a lower probability of drying out occurring in the lower canopy. This was associated with a higher species richness in the lower canopy and greater abundance of drought tolerant species in the upper canopy. There was a significant periodicity in larval abundance, biomass, species richness and body size distribution of abundant species in both tree holes, but it was not seasonal. This result indicates that unpredictable drying out of tree holes are more important drivers of tree hole community dynamics than changes in water temperature. The community of larvae in the tree hole in the upper canopy lagged behind that in the lower canopy, which indicates that most species mainly colonize the more stable microhabitats in the lower canopy. Hopefully this case study will encourage future larger-scale phenological studies to test (1) whether the patterns observed in this study can be generalized over larger spatial scales and (2) the relative importance of abiotic and biotic drivers of the dynamics of communities in tree holes. |
Implications of insect responses to supernormal visual releasing stimuli in intersexual communication and flower-visiting behaviour: A reviewReviewKarl KRALEur. 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. |
Mandible morphology reflects the type of male antagonism in the ant genus Cardiocondyla (Hymenoptera: Formicidae)Original articleChristine V. SCHMIDT, Jürgen HEINZEEur. J. Entomol. 115: 455-466, 2018 | DOI: 10.14411/eje.2018.047 The ant genus Cardiocondyla is characterized by wingless, ergatoid males, which in some species replace the typical winged male. Depending on species, ergatoid males engage in lethal fighting for access to sexual females, establish territories within their nests, or are mutually tolerant. Here we investigate, whether the morphology of ergatoid males and in particular the shape of their mandibles reflect phylogeny or male behaviour. In contrast to the worker mandible, which is relatively similar in shape in the ten species examined, mandibles of ergatoid males show a great variation in size and shape not only between the two clades of Cardiocondyla but also among species belonging to Cardiocondyla clade A. This diversity appears to reflect the diverse reproductive tactics of ergatoid males of different species, with extremely long, anteriorly oriented mandibles associated with indirect killing of adult competitors, while particularly short mandibles possibly constitute an adaptation to a tactic in which ergatoid males crush the cuticle of young rivals. |
Succession in ant communities (Hymenoptera: Formicidae) in deciduous forest clear-cuts - an Eastern European case studyOriginal articleIoan TÃUªAN, Jens DAUBER, Maria R. TRICÃ, Bálint MARKÓEur. J. Entomol. 114: 92-100, 2017 | DOI: 10.14411/eje.2017.013 Clear-cutting, the main method of harvesting in many forests in the world, causes a series of dramatic environmental changes to the forest habitat and removes habitat resources for arboreal and epigeal species. It results in considerable changes in the composition of both plant and animal communities. Ants have many critical roles in the maintenance and functioning of forest ecosystems. Therefore, the response of ants to clear-cutting and the time it takes for an ant community to recover after clear-cutting are important indicators of the effect of this harvesting technique on the forest ecosystem. We investigated ground-dwelling ant communities during secondary succession of deciduous forests in Transylvania, Romania. Using space-for-time substitution, we explored a chronosequence from clear-cuts to mature forests (> 120 years). The object was to determine if cutting has measurable effects on ant community structure, and if ant species richness differs between successional stages. We recorded a total of 24 species of ants, 11 characteristic of forests and seven of open landscape. Ant species richness was higher in clear-cuts compared to closed-canopy and old stands. Number of ant individuals was highest in young age classes and lowest in closed-canopy age classes. There was no drastic change in species richness during the succession, however differences in community composition at different stages were recorded. Open landscape species are able to rapidly colonize following disturbance but disappear when the forest sites mature and many forest ant species are capable of surviving clear cutting. |
First mitogenome for the subfamily Miltogramminae (Diptera: Sarcophagidae) and its phylogenetic implicationsOriginal articleLiping YAN, Ming ZHANG, Yunyun GAO, Thomas PAPE, Dong ZHANGEur. J. Entomol. 114: 422-429, 2017 | DOI: 10.14411/eje.2017.054 The mitochondrial genome of Mesomelena mesomelaena (Loew, 1848) is the first to be sequenced in the flesh fly subfamily Miltogramminae (Diptera: Sarcophagidae). The 14,559 bp mitogenome contains 37 typical metazoan mitochondrial genes: 13 protein-coding genes, two ribosomal RNA genes and 22 transfer RNA genes, with the same locations as in the insect ground plan. All the protein-coding genes have the start codon ATN, except for cox1 (TCG). Eight protein-coding genes have the stop codon TAA, while the remaining five have the stop codon T (cox1, cox2, nad5, and nad4) or TAG (cytb). Synonymous and non-synonymous substitution rates (Ks and Ka) for each protein-coding gene indicate that these genes evolved primarily under negative (or purifying) selection (Ka < Ks). Phylogeny of Sarcophagidae is proposed based on all the sarcophagid mitogenomes in GenBank, and the subfamily topology is reconstructed as (Sarcophaginae (Paramacronychiinae, Miltogramminae)). |
Discovery of a remarkable new species of Lymanopoda (Lepidoptera: Nymphalidae: Satyrinae) and considerations of its phylogenetic position: An integrative taxonomic approachOriginal articleTomasz W. PYRCZ, Carlos PRIETO, Pierre BOYER, Jadwiga LORENC-BRUDECKAEur. J. Entomol. 115: 387-399, 2018 | DOI: 10.14411/eje.2018.039 A new species of Lymanopoda Westwood, a cloud forest Neotropical genus of Satyrinae, is described from the páramo grasslands on an isolated, peripheral massif in the Colombian Central Cordillera of the Andes: L. flammigera Pyrcz, Prieto & Boyer, sp. n. The genus Lymanopoda is species-rich (approx. 65 species) and its alpha taxonomy is relatively well researched. Relationships within the genus using molecular data have also been explored. The new species is outstanding for its golden yellow colour in males, not found in any other neotropical Satyrinae. Cladograms were constructed based on COI sequences of 47 species of Lymanopoda (~ 70% of the known species) including 17 from Colombia. The new species segregates in the "tolima" clade, which comprises four other high altitude Colombian species, as well as two from Ecuador. However, it is the comparative analysis of male genitalia, in particular the superuncus and valvae, which identified its closest relatives, thus confirming that genital characters can help refine molecular phylogenies. In addition to identifying species using mitochondrial DNA (mtDNA barcodes), nucleotide sites with unique fixed states used to identify nine species of Lymanopoda from Colombia are also presented. |
Isolation and characterisation of the first microsatellite markers for the European stag beetle, Lucanus cervus (Coleoptera: Lucanidae)NoteNiall J. MCKEOWN, Deborah J. HARVEY, Amy J.E. HEALEY, Ilze SKUJINA, Karen COX, Alan C. GANGE, Paul W. SHAWEur. J. Entomol. 115: 620-623, 2018 | DOI: 10.14411/eje.2018.059 The European stag beetle, Lucanus cervus, is recognised as a flagship species for biodiversity conservation. Although the species is widely distributed across Europe declines have led to it being granted protected or endangered status in a number of countries and regarded as "near threatened" by the IUCN. The integration of genetic approaches into conservation efforts is urgently needed but has been impeded to date by the lack of appropriate genetic markers. To provide such a resource the development of the first microsatellite loci for stag beetle is described. Loci were identified using two methods (i) enriched library cloning (ELC) and (ii) Restriction enzyme Associated DNA sequencing (RAD-Seq). Inefficient microsatellite detection using the ELC method suggests that RAD-Seq, or other Next Generation Sequencing based methods, may ultimately be more cost effective for obtaining informative suites of markers for this and other coleopteran species. 18 loci were characterised by genotyping 42 UK specimens collected as prey leftover/roadkill. All loci produced unambiguous genotypes and were polymorphic. Though preliminary, estimates of genetic variability suggest UK populations may be genetically depauperate. The microsatellite loci represent a suite of genetic markers that can be applied to non-invasive population monitoring and numerous other areas of Lucanus conservation and evolutionary research. |



