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Diversity of adipokinetic hormones in termites (Isoptera)Original articleVeronika JEDLIČKOVÁ, Pavel JEDLIČKA, Barbora ©PULÁKOVÁEur. J. Entomol. 113: 364-371, 2016 | DOI: 10.14411/eje.2016.047 In this study we report on the structural diversity of adipokinetic hormones (AKHs) in the evolutionarily oldest group of social insects, the termites (Isoptera). Using molecular methods combined with in silico bioinformatic analysis, we studied and compared the sequences coding for these neuropeptides in thirteen species of five families of Isoptera. There are three types of AKH octapeptides in termites: Empusa pennata adipokinetic hormone (Emppe-AKH; pQVNFTPNWamide), Microhodotermes viator corpus cardiacum peptide (Micvi-CC; pQINFTPNWamide) and Periplaneta americana cardioaccelerating hormone (Peram-CAH-I; pQVNFSPNWamide). Of these the Peram-CAH-I was the most frequently bioactive form detected in representatives of four out of the six families studied. The complete AKH preprohormones in the termites studied shared at least an 84% amino acid similarity. In agreement with current phylogenetic scenarios of termites as an internal monophyletic clade nested within cockroaches (Blattaria) in the proximity of the family Blattidae, our phylogenetic analysis of the AKH precursor sequences (in the absence of data for the Cryptocercidae) placed the Blattidae (Periplaneta americana) as a sister group of termites and the AKHs of other cockroach families (Blattellidae and Blaberidae) were more divergent from those of termites. Representatives of the basal termite families Mastotermitidae and Archotermopsidae (but also one rhinotermitid genus Prorhinotermes) occurred separately from the phylogenetically advanced lineage (Rhinotermitidae and Termitidae), and Neotermes (Kalotermitidae) was sister to all other termites included. |
Growth and development in a lepidopteran with variable instar number, Pseudocoremia suavis (Geometridae), under standard rearing conditions and when parasitised by Meteorus pulchricornis (Hymenoptera: Braconidae)Emma I. BARRACLOUGH, Elisabeth P.J. BURGESS, Aliesha M. KEAN, Louise A. MALONEEur. J. Entomol. 111 (4): 501-511, 2014 | DOI: 10.14411/eje.2014.062 Though extra instars are often associated with poor conditions and thought to be a compensation for a low growth rate, the reasons why they are necessary, and for variable instar number existing under standard rearing conditions, are not yet clear. In standard rearing conditions, approximately half of Pseudocoremia suavis larvae had five instars (Type I larvae), and half six instars (Type II larvae). Type II larvae took longer to pupate and reached higher pupal weights than Type I larvae. The extra instar was not related to sexual size dimorphism; Type II larvae were not more likely to be females. Females of both Types pupated later than males and had higher pupal weights; this weight gain was achieved wholly via an extended final instar. Relative growth rates (RGR), instar durations and larval weights on weigh days were otherwise the same for both sexes. For most of the larval period, Type II larvae had lower RGR and lower weights than Type I larvae. They also had shorter 3rd, 4th and 5th instars than Type I larvae, and the estimated weights at each moult were significantly lower. The Types are discussed in terms of being, in species with weight thresholds for pupation, not optional "strategies" involving different critical weight ratios for larval moults, but as an inevitable consequence of physiological timing constraints upon reaching the critical weights for larval moults causing large variation in size after the moult. Small larvae may then need an extra instar to reach pupation. When parasitised in the second instar by Meteorus pulchricornis, P. suavis larvae produced parasitoids in either their fourth (4th instar emerging (IE)) or fifth instar (5th IE). The estimated moulting weights at each instar of 4th IE and 5th IE hosts were very similar to those of Type I and Type II unparasitised larvae respectively, which, together with similarity of instar duration patterns, is strongly suggestive of Types being present within parasitised larvae. The proportion of 5th IE hosts in the much slower-growing parasitised treatment was greater than the proportion of Type II larvae in the unparasitised treatment, as might be expected if Type II is associated with lower RGR. The lack of further Types appearing is consistent with extra instars being a compensation for small weight after the moult rather than low RGR per se. |
Temporal variations in the life-cycles of aphids (Sternorrhyncha: Aphididae) and their coccinellid predatorsMohamed El Fodhil AROUN, Bahia DOUMANDJI-MITICHE, Daniel PETIT, Zahr-Eddine DJAZOULIEur. J. Entomol. 112 (3): 432-439, 2015 | DOI: 10.14411/eje.2015.060 Aphids are either monoecious living either on trees or herbaceous plants, or heteroecious, which involves host alternating between a tree (primary host) and a herbaceous plant (secondary host). We described the temporal variations in abundance and richness of aphids in an Algerian orchard, over a 6 month period. We recorded the choice of basin colour, the relative height of traps, and monthly Barycenter of winged populations. We also recorded temporal variations in the structure of ladybird communities. Tree-living species of aphids are the last to be caught with most caught by the yellow traps, possibly because of the predominant greenness of the vegetation in April. Most were also caught by high traps. Their phenology coincides with that of the second peak of ladybirds. In contrast, the phenology of species of aphids living on herbaceous plants differs greatly, which reflects their host plant diversity. In March relatively more of these aphids were caught by the green traps, possibly because at that time the ground was not yet covered by vegetation. Early and late species of aphids are at greater risk of being attacked by ladybirds as they are also most active early and late in the season. The highest catches of the heteroecious species of aphids were recorded in the middle of the trapping period and between those of the two groups of monoecious species of aphids. The adaptive significance of the differences in the behaviour and ecology of the aphids in the three groups is discussed. |
Prey detection in carabid beetles (Coleoptera: Carabidae) in woodland ecosystems by PCR analysis of gut contentsLucija ©ERIĆ JELASKA, Damjan FRANJEVIĆ, Sven D. JELASKA, William O.C. SYMONDSONEur. J. Entomol. 111 (5): 631-638, 2014 | DOI: 10.14411/eje.2014.079 Predatory carabid beetles are important for regulating prey abundance in terrestrial ecosystems. While surveys of carabid diet have revealed many insights into trophic interactions, the high species diversity and heterogeneous developmental stages of prey identified in the gut have made further advances difficult. In addition, the carabid gut contains partially digested and mainly soft tissue parts of the prey species, difficult to identify by traditional methods. Molecular gut content analysis (MGCA) avoids these disadvantages but to date has been limited primarily to revealing pest species in agricultural fields. Here we used MGCA to screen for the presence of Lepidoptera in carabid guts, in woodland ecosystems, in both Croatia and the UK. Data on carabids positive for Lepidoptera were compared with those from previous work on the same carabid assemblages, screened for earthworms, slugs, woodlice and springtails. In both locations, the prey group most frequently detected was earthworms, followed by slugs and Lepidoptera and then finally by woodlice and springtails. The composition of the diet changed with season, carabid sex, and carabid size. In both locations, Lepidoptera were the third most frequent prey, with 27% of carabids testing positive in Croatia and 20% in UK, suggesting that carabids could be significant predators of Lepidoptera in woodland ecosystems and may potentially play an important role in controlling moth pests. |
Development, reproduction, host range and geographical distribution of the variegated caper bug Stenozygum coloratum (Hemiptera: Heteroptera: Pentatomidae)Shahar SAMRA, Murad GHANIM, Alex PROTASOV, Zvi MENDELEur. J. Entomol. 112 (2): 362-372, 2015 | DOI: 10.14411/eje.2015.041 The variegated caper bug (CB) Stenozygum coloratum (Klug, 1845) is common in the Eastern Mediterranean region and a minor agricultural pest. CB eggs were recently shown to serve as alternative hosts for Ooencyrtus pityocampae Mercet, 1921, an important natural enemy of the pine processionary moth (PPM) Thaumetopoea wilkinsoni Tams, 1924 (Lepidoptera: Notodontidae). In this study various aspects of the life history of CB were studied, including its distribution, host range, development, reproduction and ability to develop on various cultivated species of plants. CB occurs in almost all areas and habitats in Israel, except in the coldest regions, attacking several caper species (Capparis spp.). When reared on Capparis zoharyi at 25°C, one generation lasted 6 weeks and females laid a single 12-egg cluster every 3 days. Decreases in temperature, but not changes in day length, terminated reproductive activity. CB nymphs survived for up to three months, or even completed their development, on some agricultural plants. However, reproductive activity was initiated only if adults were fed capers. These findings emphasize the importance of capers in the CB life cycle and account for why other plants are rarely attacked. These plants may serve as a temporary refuge for CB when capers are scarce or unsuitable, mainly late in the season. Morphology of developmental stages, egg deposition, cannibalistic behaviour, sex ratio and effects of temperature on egg production were also studied. The possibility of using CB for enhancing the biological control of PPM is discussed. |
Evaluation of the diet of a carabid predator using fluorescent marking of preyJan OKROUHLIK, Pavel FOLTANEur. J. Entomol. 112 (3): 477-485, 2015 | DOI: 10.14411/eje.2015.054 We present a UV-fluorescent dye-based prey marking technique, using three different dyes, with later detection of the dyes in the guts of predators using a micro-plate fluorescent reader. By using this new method of detecting dyes based on their different excitation and emission characteristics it is possible to simultaneously screen 96 samples for multiple fluorescent-markers in less than 30 minutes. The marking is stable, cheap, non-toxic and had no effect on the choice of the carabid predator Pterostichus melanarius between marked and unmarked fly larvae (Musca domestica). Different fluorescent dyes provide variable detection intervals up to 100% detectability at 96 h post-ingestion by this predator. The simple marking, extraction and detection methods presented could be used in food web research to map individual trophic links and predator preference for different types of prey. |
Invasive chestnut gall wasp Dryocosmus kuriphilus (Hymenoptera: Cynipidae), its native parasitoid community and association with oak gall wasps in SloveniaKatarina KOS, Eva KRISTON, George MELIKAEur. J. Entomol. 112 (4): 698-704, 2015 | DOI: 10.14411/eje.2015.091 The Asian chestnut gall wasp (ACGW), Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae), is a global pest of chestnut trees. This pest was first recorded in Slovenia in 2005. Despite strict phytosanitary measures it was present throughout the country in native chestnut stands by 2013. We provide here the first overview of the parasitoids of ACGW in Slovenia recorded over a 4-year period and the direct interactions between parasitoid communities attacking hosts on chestnut and oaks at the same sites. A total of 27 species of native parasitoids that normally parasitize oak cynipids emerged from ACGW galls. The most abundant species were Torymus flavipes and Eupelmus urozonus. Seven species appear to be geographically well distributed in Slovenia. Twelve species of oak gall wasp were parasitized by 19 species of parasitoids. All native parasitoids have broad host ranges, so a large parasitoid diversity within this community can be expected. This is a novel study comparing the parasitoid communities associated with chestnut and oak galls. |
Descriptions of larvae of Megadytes (Coleoptera: Dytiscidae: Dytiscinae): The subgenera Trifurcitus and Megadytes s. str., ground plan of chaetotaxy of the genus and phylogenetic analysisMariano C. MICHATEur. J. Entomol. 107 (3): 377-392, 2010 | DOI: 10.14411/eje.2010.047 The three larval instars of Megadytes (M.) carcharias Griffini and M. (Trifurcitus) fallax (Aubé) are described and illustrated in detail for the first time, with an emphasis on morphometry and chaetotaxy of the cephalic capsule, head appendages, legs, last abdominal segment and urogomphi. The ground plan of chaetotaxy of the genus Megadytes Sharp is described and illustrated based on three of the four recognised subgenera. First-instar larvae of Megadytes are characterised by the presence of a large number of additional sensilla on almost every part of the body. Primary chaetotaxy of the subgenera (Bifurcitus Brinck based on third instar) is very similar, with few differences including (1) shape of the setae on the anterior margin of the frontoclypeus; (2) presence or absence of a ring of multi-branched setae on distal third of mandible; and (3) number of setae on the urogomphus. A cladistic analysis of Dytiscidae, based on 169 larval characters and 34 taxa, indicates that: (1) Trifurcitus Brinck deserves generic status; (2) Cybistrini are not closely related to Hydroporinae; (3) the absence of a galea in Cybistrini is a secondary loss independent of that in Hydroporinae; (4) Cybistrini are well supported by many characters (including several aspects of first-instar chaetotaxy). |
Different steps in the evolution of neo-sex chromosomes in two East African Spalacomimus species (Orthoptera: Tettigoniidae: Hetrodinae)Elżbieta WARCHAŁOWSKA-¦LIWA, Beata GRZYWACZ, Anna MARYAŃSKA-NADACHOWSKA, Andreas HEMP, Claudia HEMPEur. J. Entomol. 112 (1): 1-10, 2015 | DOI: 10.14411/eje.2015.024 Two orthopteran species belonging to the East African genus Spalacomimus, S. verruciferus and S. talpa (Tettigoniidae: Hetrodinae), were investigated using both molecular cytogenetic techniques, including fluorescence in situ hybridization with 18S rDNA and (TTAGG)n telomeric probes, and classical techniques, such as C-banding, fluorochrome CMA3/DAPI staining, and silver impregnation. These techniques allowed us to identify cytogenetic markers that were then used to elucidate chromosome organization and differences between species. Chromosomal complements are reported for the first time for both analyzed species, which showed the same chromosomal number of 2n = 24 and the neo-XY sex chromosome system; however, the morphology of neo-sex chromosomes differs between these species. A cluster of the major rDNA (i.e., the nucleolar organizer region, NOR) was found to be located in the interstitial region of the sex chromosomes of S. verruciferus, whereas it was on the long pair of autosomes in S. talpa. The difference between the karyotypes of the studied species indicate divergent origins of their neo-XY systems. A detailed description of the structure and behaviour of the sex chromosome configuration in male meiosis is provided. In S. verruciferus, the neo-XY system is derived from a Robertsonian fusion between the original acrocentric X and an acrocentric long pair of autosomes bearing an rDNA/NOR locus, leading to a bi-armed X and an acrocentric neo-Y chromosome. The neo-XY in S. talpa arose due to complicated rearrangements, attributable to a tandem fusion between the original acrocentric X and part of a medium-sized autosome, and resulting in supernumerary chromosomes. In the latter case, behaviour of the neo-X and neo-Y demonstrates a post-reductional division of these chromosomes. Variation in the evolution of two neo-XY sex chromosome systems are novel phylogenetic markers for the Hetrodinae and seem to promote speciation as important aspect for taxonomy. |
Evidence of forage distance limitations for small bees (Hymenoptera: Apidae)Ivan R. WRIGHT, Stuart P.M. ROBERTS, Bonnie E. COLLINSEur. J. Entomol. 112 (2): 303-310, 2015 | DOI: 10.14411/eje.2015.028 The distribution of ground-nesting bees was investigated using transects of water traps in a mosaic of nesting and forage habitats at Shotover Hill in Oxfordshire, UK. The site includes a large area of ground-nesting bee activity and is adjoined on three sides by floristic hay meadows. This study showed that the females of small bee species (< 1.5 mm intertegular span) that were foraging in the hay meadows demonstrated a functional limitation to their homing range. The abundance of small bees declined rapidly with increasing distance from areas of high density nesting; declining more rapidly than might be expected from uniform dispersal into the surrounding landscape. By modelling the occurrence of bees along each transect it was found that the probability of observing a small bee in the hay meadows was reduced to 10% at a distance of 250-370 m from the nesting habitat. The result emphasises the scale on which habitat fragmentation will begin to impact upon bee diversity, and the relative contribution of managed "pollen and nectar" strips to areas of nesting habitat. |
Age dependent mate choice influences reproductive and progeny attributes in aphidophagous ladybird beetles (Coleoptera: Coccinellidae)Mahadev BISTA, OMKAREur. J. Entomol. 112 (4): 648-657, 2015 | DOI: 10.14411/eje.2015.082 Despite the many studies on age based mate choice in insects, the question of how age influences mate choice in predaceous ladybird beetles is still unexplored. The present study evaluates age based mate choice in two sympatric aphidophagous ladybirds, Coccinella septempunctata L. and Coccinella transversalis Fab., in terms of mating behaviour (latent period, number of bouts, bout interval and duration of wriggling movements and mating), fecundity, egg viability and the development and survival of their progeny. Results revealed that middle aged (30-40 days) mates were preferred by young (10-15 days post-eclosion), middle aged (30-40 days) and old (45-55 days) individuals of both sexes. Mating behaviour and egg viability differed significantly with male age whereas fecundity, offspring development and survival differed significantly with female age. The shortest latent periods and bout intervals, highest numbers of bouts, longest durations of wriggling movements and mating, and maximum egg viability were recorded for middle aged males whereas fecundity, percentage pupation and adult emergence of offspring were highest and durations of immature development were shortest for middle aged females. Thus, the present study indicates that middle aged individuals of C. septempunctata and C. transversalis are most preferred as mates as they have the highest reproductive output and produce the fittest offspring. |
Laboratory rearing of Sycanus annulicornis (Hemiptera: Reduviidae) on two species of prey: Differences in its biology and efficiency as a predator of the nettle caterpillar pest Setothosea asigna (Lepidoptera: Limacodidae)Original articleAbdul SAHID, Wahyu D. NATAWIGENA, HERSANTI, SUDARJATEur. J. Entomol. 115: 208-216, 2018 | DOI: 10.14411/eje.2018.019 Setothosea asigna van Eecke is a dominant defoliator pest in oil palm plantations. To control this pest, a generalist predatory bug, Sycanus annulicornis Dohrn, was used as it is easy to rear on several different species of prey. In this study, we evaluated the influence of different prey on the biology and the ability of S. annulicornis to attack and kill the nettle caterpillar pest S. asigna. Based on laboratory rearing, the larvae of Crocidolomia pavonana F. (Lepidoptera: Crambidae) is a suitable prey for both the growth and development of S. annulicornis, as its nymphal development is shorter (74.0 ± 7.3 days) and adult longevity longer (81.0 ± 9.0 days for male and 64.8 ± 12.4 days for female, respectively) than when reared on the larvae of Tenebrio molitor L. (Coleoptera: Tenebrionidae) (44.0 ± 16.7 days for male and 52.6 ± 14.4 days for female). However, S. annulicornis reared on T. molitor larvae attacked 2.0-2.2 larvae of S. asigna per day, which is more than the 1.6-1.7 larvae per day of those reared on C. pavonana, which indicates that the larvae of T. molitor are a more effective diet for rearing S. annulicornis as biocontrol agent for the S. asigna. |
Survey and DNA barcoding of flat bugs (Hemiptera: Aradidae) in the Tanzanian Forest Archipelago reveal a phylogeographically structured fauna largely unknown at the species levelOriginal articleVasily V. GREBENNIKOV, Ernst HEISSEur. J. Entomol. 115: 512-523, 2018 | DOI: 10.14411/eje.2018.051 We report results of a faunal survey of Aradidae flat bugs sampled by sifting litter in 14 wet and discrete Tanzanian primary forests (= Tanzanian Forest Archipelago, TFA) of different geological origins and ages. Images, locality data and, when available, DNA barcoding sequences of 300 Aradidae adults and nymphs forming the core of the herein analyzed data are publicly available online at dx.doi.org/10.5883/DS-ARADTZ. Three Aradidae subfamilies and seven genera were recorded: Aneurinae (Paraneurus), Carventinae (Dundocoris) and Mezirinae (Afropictinus, Embuana, Linnavuoriessa, Neochelonoderus, Usumbaraia); the two latter subfamilies were also represented by specimens not assignable to nominal genera. Barring the six nominal species of Neochelonoderus and Afropictinus described earlier by us from these samples and representing 11 of the herein defined Operational Taxonomic Units (OTU), only one of the remaining 52 OTUs could be assigned to a named species; the remaining 51 OTUs (81%) represent unnamed species. Average diversity of Aradidae is 4.64 species per locality; diversity on the three geologically young volcanoes (Mts Hanang, Meru, Kilimanjaro) is significantly lower (1.33) than on the nine Eastern Arc Mountains (5.67) and in two lowland forests (5). Observed phylogeographic structure of Aradidae in TFA can be attributed to vicariance, while the depauperate fauna of Aradidae on geologically young Tanzanian volcanoes was likely formed anew by colonisation from nearby and geologically older forests. |
Identification and expression patterns of chemosensory proteins in the black-back prominent moth, Clostera restitura (Lepidoptera: Notodontidae)Original articleHui LI, Tianzi GU, Changyu CHEN, Kairu HUANG, Ruixu CHEN, Dejun HAOEur. J. Entomol. 116: 372-391, 2019 | DOI: 10.14411/eje.2019.039 Insects have evolved highly specific and sensitive olfactory sensory systems to detect plant hosts and mates. Chemosensory proteins (CSPs) play an important role in this process, but in this respect there is limited information on Clostera restitura, one of the most destructive defoliators of poplars in China. In the present study, we first identified seven candidate CSPs in C. restitura. Sequence alignment and phylogenetic analysis showed that these candidate proteins possessed typical characteristics of the insect CSP family and were similar to those of other Lepidoptera. These genes were expressed in different developmental stages and tissues, and the levels of expression differed after mating. Some CresCSPs were more associated with development and others with mating. They may play an important role in host recognition, egg development and mating behaviour. Furthermore, the CSPs were ubiquitously detected in all tissues and most of them were highly expressed in antennae, especially female antennae. We suggest the CresCSPs may contribute to female oviposition site recognition. CresCSPs that are highly transcribed in wings and legs, may function in gustation. This study provides a better understanding of the molecular mechanisms of olfaction in C. restitura and environmentally friendly pest management strategy for controlling C. restitura. |
Methods for retaining well-preserved DNA with dried specimens of insectsOriginal articleNaoyuki NAKAHAMA, Yuji ISAGI, Motomi ITOEur. J. Entomol. 116: 486-491, 2019 | DOI: 10.14411/eje.2019.050 Dried specimens of insects are increasingly seen as genetic resources. However, genetic analysis of dried specimens of insects is hampered by the deterioration of the DNA. In this study, we developed methods for preparing dried specimens of insects with well-preserved DNA, mainly for PCR-based genetic analysis. First, we compared the effects of either exposure to ethyl acetate vapour for from 10 min to 6 h or by freezing on the fragmentation of DNA in order to determine optimal length of time needed for killing insects using the above methods. Second, we compared the fragmentation of DNA after preservation by drying or immersion of legs in 99.5% ethanol or 99% propylene glycol in 0.2-ml tubes. We assessed degrees of fragmentation of DNA by determining polymerase chain reaction (PCR) success rates with primers for 313-, 710- and 1555-bp fragments using DNA that was collected immediately, and at one, six and 12 months after preparing the specimens. Differing times taken to kill insects did not affect the fragmentation of DNA. In dried specimens, DNA was seriously fragmented after one month, whereas that in legs prepared by immersion in 99.5% ethanol or 99% propylene glycol contained long fragments of DNA (1555 bp~) after 12 months. Propylene glycol was more suitable for preservation than ethanol, because the latter evaporates. Thus, to preserve insect DNA we suggest inserting the pin on which an insect is impaled into the hinged lid of a 0.2-ml tube containing 99% propylene glycol so that when the lid is closed the legs of the insect are preserved in the solution. |
Bait visitation by Formica lemani (Hymenoptera: Fomicidae) indicates shortage of carbohydrates in alpine grasslandsOriginal articleElia GUARIENTO, Jan MARTINI, Konrad FIEDLEREur. J. Entomol. 115: 217-222, 2018 | DOI: 10.14411/eje.2018.020 Insights can be gained by analysing the feeding decisions of animals in terms of nutrient demands at a species or community level. Using carbohydrate and protein food baits, resource use and food preferences of Formica (Serviformica) lemani were determined at nine locations situated at different altitudes (1875 to 2400 m a.s.l.) in the alpine grassland belt above the tree line in Austria and northern Italy. F. lemani is the most common species of ant in this habitat. Sucrose baits placed around ant colonies were visited by significantly (3.9 times) more workers than protein baits. This indicates that sources of sugar (carbohydrate) are in short supply in the alpine zone, whereas availability of prey items appears to be less constraining. Overall, we recorded a decrease in the incidence of visits to baits from low (31.9% baits attracting ants at least once) to high altitudes (16.7%). Foraging ants never visited 51.5% of the baits exposed for periods of 75 min. This indicates that with increasing altitude competition for food among ant colonies becomes less intense in alpine grassland ant communities. |
Harmonia axyridis (Coleoptera: Coccinellidae): Smelling the rat in native ladybird declinesPoint of viewJohn J. SLOGGETTEur. J. Entomol. 114: 455-461, 2017 | DOI: 10.14411/eje.2017.058 In the last two decades a huge amount of research has focused on the invasive harlequin ladybird, Harmonia axyridis, particularly on potential or actual deleterious effects that have arisen after it has colonised new regions. A focus of this work has been real or anticipated declines in native ladybird abundance since the introduction of H. axyridis, for which it is deemed responsible. Scientists have generally painted a very bleak picture of the effects of H. axyridis on native species: in this paper I argue that the picture painted is often too bleak. I use the case of the 2-spot ladybird, Adalia bipunctata, the species most often invoked as threatened by H. axyridis, to illustrate my point. While there is little question that H. axyridis has led to a decline in A. bipunctata populations in Europe, it seems likely that prior to the invasive ladybird's arrival A. bipunctata occurred in artificially high numbers in the urban environments in which it was typically studied. Pollution in towns and cities led to enhanced numbers of prey aphids on plants there which initially favoured A. bipunctata, and later H. axyridis. Thus one species, A. bipunctata, that has benefitted from an association with humans has been replaced by another, H. axyridis, just as brown rats replaced black rats in Europe and North America. Viewed with a longer perspective, A. bipunctata has more likely declined back to pre-industrial levels: the artificially high level from which it has declined recently was not a 'natural' one, and thus its decline from this level does not imply that it is now threatened or endangered. More broadly, we need a wider perspective, encompassing other ladybirds, longer timeframes and better comparisons with other (non-ladybird) invasive species to more clearly assess whether H. axyridis really poses as much of a threat as is often proposed. |
Annotated checklist of the plant bug tribe Mirini (Heteroptera: Miridae: Mirinae) recorded on the Korean Peninsula, with descriptions of three new speciesOriginal articleMinsuk OH, Tomohide YASUNAGA, Ram Keshari DUWAL, Seunghwan LEEEur. J. Entomol. 115: 467-492, 2018 | DOI: 10.14411/eje.2018.048 An annotated checklist of the tribe Mirini (Miridae: Mirinae) recorded on the Korean peninsula is presented. A total of 113 species, including newly described and newly recorded species are recognized. Three new species, Apolygus hwasoonanus Oh, Yasunaga & Lee, sp. n., A. seonheulensis Oh, Yasunaga & Lee, sp. n. and Stenotus penniseticola Oh, Yasunaga & Lee, sp. n., are described. Eight species, Apolygus adustus (Jakovlev, 1876), Charagochilus (Charagochilus) longicornis Reuter, 1885, C. (C.) pallidicollis Zheng, 1990, Pinalitopsis rhodopotnia Yasunaga, Schwartz & Chérot, 2002, Philostephanus tibialis (Lu & Zheng, 1998), Rhabdomiris striatellus (Fabricius, 1794), Yamatolygus insulanus Yasunaga, 1992 and Y. pilosus Yasunaga, 1992 are reported for the first time from the Korean peninsula. Korean specimens previously identified as Eurystylus luteus Hsaio, 1941 are correctly recognized as E. sauteri Poppius, 1915. Three new synonyms are proposed: Apolygus atriclavus Kim & Jung, 2016 syn. n. of A. xanthomelas Yasunaga & Yasunaga, 2000, A. josifovi Kim & Jung, 2016 syn. n. of A. subpulchellus (Kerzhner, 1988) and Capsus koreanus Kim & Jung, 2015 syn. n. of C. wagneri Remane, 1950. Dorsal habitus photographs of the newly described or recorded species are presented along with figures of the genitalia of the new species. Keys to Korean genera and to species of Apolygus and Stenotus are provided. Zoogeography of the East Asian Mirini fauna is also discussed. |
Biometry of the large dragonfly Anax imperator (Odonata: Aeshnidae): A study of traits from larval development to adultsOriginal articleMarceau MINOT, Mickaël LE GALL, Aurélie HUSTÉEur. J. Entomol. 116: 269-280, 2019 | DOI: 10.14411/eje.2019.031 Insect larval development affects adult traits but the biometric relationships are usually poorly understood, including large odonates. In this study, measurements of morphological traits of larvae, exuviae and adults of Anax imperator were recorded. They were used to investigate the effects of early development on adult morphology. Results showed an increase in larval length during the final instar and the length of its exuviae significantly exceeded that of the larva. Length and body mass of teneral adults were strongly related to the length of their exuviae. Adult males were significantly longer than adult females, while both had the same body mass at emergence. Length of teneral adults was negatively related to the date of emergence in both sexes. During maturation, body mass of males only increased slightly whereas that of females increased greatly. Mature specimens were also significantly longer than teneral individuals. Body mass of mature males and length of mature females were both associated with the date of capture. Wing length did not differ between sexes or from data available from Great Britain. This study underscores the importance of taking into account larval growth in order to better understand the adult traits of odonates. |
Book Review: Hubble D. 2017: Leaf Beetles. Ecology and Identification. Naturalists' Handbook 34.Book reviewJ. BEZDĚKEur. J. Entomol. 116: 92, 2019 | DOI: 10.14411/eje.2019.010 Hubble D. 2017: Leaf Beetles. Ecology and Identification. Naturalists' Handbook 34. Pelagic Publishing, Exeter, 149 pp. ISBN 978-1-78427-150-3. Price GBP 19.99. |
Book Review: The Western Palaearctic Zygaenidae.NAUMANN C.M., TARMANN G.M., TREMEWAN W.G.: THEEur. J. Entomol. 96 (4): 458, 1999 Naumann C.M., Tarmann G.M. & Tremewan W.G.: The Western Palaearctic Zygaenidae. Apollo Books, Stenstrup, 1999, 304 pp. 12 colour plates. |
Rates of molecular evolution and genetic diversity in European vs. North American populations of invasive insect speciesOriginal articleRobert G. YOUNG, T. Fatima MITTERBOECK, Tzitziki LOEZA-QUINTANA, Sarah J. ADAMOWICZEur. J. Entomol. 115: 718-728, 2018 | DOI: 10.14411/eje.2018.071 Many factors contribute to the 'invasive potential' of species or populations. It has been suggested that the rate of genetic evolution of a species and the amount of genetic diversity upon which selection can act may play a role in invasiveness. In this study, we examine whether invasive species have a higher relative pace of molecular evolution as compared with closely related non-invasive species, as well as examine the genetic diversity between invasive and closely related species. To do this, we used mitochondrial cytochrome c oxidase subunit I sequences of 35 species with a European native range that are invasive in North America. Unique to molecular rate studies, we permuted across sequences when comparing each invasive species with its sister clade species, incorporating a range of recorded genetic variation within species using 405,765 total combinations of invasive, sister, and outgroup sequences. We observed no significant trend in relative molecular rates between invasive and non-invasive sister clade species, nor in intraspecific genetic diversity, suggesting that differences in invasive status between closely related lineages are not strongly determined by the relative overall pace of genetic evolution or molecular genetic diversity. We support previous observations of more often higher genetic diversity in native than invaded ranges using available data for this genetic region. |
Afromuelleria, a new genus of Trachyphloeini from Limpopo, with descriptions of four new species (Coleoptera: Curculionidae: Entiminae)Original articleRoman BOROVEC, Jiří SKUHROVECEur. J. Entomol. 115: 668-683, 2018 | DOI: 10.14411/eje.2018.066 A new genus, Afromuelleria gen. n., assigned to the tribe Trachyphloeini Lacordaire, 1863, is described for four South African species of weevils: A. awelani sp. n., A. baobab sp. n., A. limpopo sp. n. and A. venda sp. n. All species are illustrated and keyed. Taxonomic status of the new genus is discussed and compared with similar genera of Trachyphloeini and Embrithini Marshall, 1942. |
A key to genera of South American Deltocephalini (Hemiptera: Cicadellidae: Deltocephalinae) with descriptions of new taxa and nomenclatural changesOriginal articleYani DUAN, Christopher H. DIETRICHEur. J. Entomol. 115: 587-601, 2018 | DOI: 10.14411/eje.2018.056 A key to genera of South American Deltocephalini Dallas, 1870 based on adult males is presented. Two new genera, each based on a single new species from Argentina are described and illustrated: Corrientesia gen. n. based on type species C. ochrescens sp. n. and Salnogia gen. n. based on type species S. fletcheri sp. n. A new species of Graminella DeLong, 1936, G. schrocki sp. n. from Argentina is also described and illustrated. Graminella stelliger (Berg, 1884) equals Fusanus acristylus Cheng, 1980, syn. n. A new combination, Limpica pallida (Linnavuori & DeLong, 1979) comb. n., transferred from Reventazonia Linnavuori, 1959, is also proposed. Quaziptus Kramer, 1965, is returned from Paralimnini Distant, 1908 to Deltocephalini Dallas, 1870. |
Female fertility in Hippodamia convergens (Coleoptera: Coccinellidae) is maximized by polyandry, but reduced by continued male presenceMohamed H. BAYOUMY, J.P. MICHAUDEur. J. Entomol. 111 (4): 513-520, 2014 | DOI: 10.14411/eje.2014.067 Many species of lady beetles are highly promiscuous and females mate repeatedly even when not sperm-limited. We quantified female reproductive success and progeny development in Hippodamia convergens using a laboratory experiment designed to test whether (1) male novelty (different males), (2) male mating status (virgin, non-virgin) or (3) opportunities for female mate choice, would increase female fitness compared to a similar number of matings with the same male. Daily access to novel males, regardless of their mating status, increased the egg fertility of females, but not their fecundity. Opportunities for mate choice did not improve any measure of female reproductive success compared to arbitrary assignment of males, but slightly increased reproductive rate, as measured by the number of days to produce 15 clutches. The eggs of monogamous females had the fastest eclosion times, but larval development was fastest for progeny of females polyandrous with non-virgin males, and total developmental time did not differ among treatments. In a second experiment, confinement with two males during oviposition disrupted egg clustering and reduced egg fertility, but not female fecundity, relative to confinement with one male or oviposition in solitude, suggesting a negative impact of male harassment on female fitness in the presence of multiple males. However, the continued presence of two males also improved progeny survival and reduced progeny development time relative to female confinement with one, likely due to summation of paternal effects when females were allowed unlimited matings with both males. These results do not rule out genetic benefits of polyandry, but support the view that enhanced egg fertility is a primary benefit, and suggest more subtle benefits may be obtained in the form of additive paternal effects. The average number of female matings in nature may even exceed that required to obtain such benefits if females use "convenience polyandry" to diminish male harassment. |
Aestivo-hibernation of Coccinella septempunctata (Coleoptera: Coccinellidae) in a mountainous area in southern Turkey: Is dormancy at high altitudes adaptive?Özlem GÜVEN, Hasan GÖLLÜOĞLU, Piotr CERYNGIEREur. J. Entomol. 112 (1): 41-48, 2015 | DOI: 10.14411/eje.2015.002 Each year huge numbers of adults of Coccinella septempunctata occupy aestivo-hibernation sites on Uludaz Hill, Çimen Mountain in the Kahramanmaraş Province of Turkey. In 2008 and 2009 we investigated the phenology, population dynamics, mortality and natural enemies of C. septempunctata arriving on Uludaz Hill. Samples were collected once a month during the snow-free season (April-November) from the top of the hill (2273 m a.s.l.) and at two lower altitudes (1900 m a.s.l. and 2050 m a.s.l.) on the slopes of the hill. In both years C. septempunctata was clearly more abundant at the top of the hill than at the two lower altitudes, which is in accordance with the hypothesis that beetles migrating to dormancy sites are strongly attracted to sites at the highest altitudes. Numbers of C. septempunctata on the hill were low in April and May. The large increase in abundance recorded in June may be attributed to the arrival of a new generation from lowland breeding sites. Emergence of previous year colonizers from their winter shelters is less probable due to the high fat content of the beetles collected in June. Spring dispersal from the hill to lowland areas was not observed. We suppose that this dispersal was either prevented by low temperature or considerably delayed and not synchronized with the period of ladybird breeding activity in the surrounding lowlands. In addition, the C. septempunctata aestivo-hibernating on Uludaz Hill suffered very high mortality, mainly caused by entomopathogenic fungi of the genus Beauveria. The results of our study are discussed in terms of the ecological trap concept. |
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. |
Origins and genetic diversity of the ragweed beetles, Ophraella communa (Coleoptera: Chrysomelidae), that were introduced into Italy and Japan based on an analysis of mitochondrial DNA sequence dataYudai NISHIDE, Yuya FUKANO, Hayato DOI, Toshiyuki SATOH, Hiroki INOUE, Marco BORIANIEur. J. Entomol. 112 (4): 613-618, 2015 | DOI: 10.14411/eje.2015.086 Ophraella communa (Coleoptera: Chrysomelidae) is an oligophagous herbivorous beetle that feeds on Ambrosia artemisiifolia. It is native to North America, but was accidentally introduced into Japan in 1995 and Europe in 2013. We analyzed partial DNA sequences of the mitochondrial cytochrome oxidase II gene for O. communa collected from 29 locations in the United States, Japan and Italy. Overall, the results of our analyses indicate that the introduced Japanese populations have lower genetic variation than the native populations. The sequences for the Italian specimens did not share haplotypes with Japanese specimens. These results indicate that the introduced Japanese populations originated from a single introduction, and that the Italian and Japanese populations have different origins. |
Numerical response of Nesidiocoris tenuis (Hemiptera: Miridae) preying on Tuta absoluta (Lepidoptera: Gelechiidae) in tomato cropsJuan A. SANCHEZ, Michelangelo LA-SPINA, Alfredo LACASAEur. J. Entomol. 111 (3): 387-395, 2014 | DOI: 10.14411/eje.2014.041 Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is an effective predator of pests of tomato crops and a promising biocontrol agent of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in the Mediterranean area. The aim of this study was to determine the numerical response of N. tenuis to different levels of abundance of T. absoluta and its potential for controlling it when infesting tomato crops. The effects of infesting plants with either 0.2 or 2 larvae of T. absoluta and releasing either 2 or 0 adults of N. tenuis per plant were assayed in a complete factorial randomised-block design with 3 repeats in 12 greenhouse compartments in southern Spain. The population dynamics of the moth was similar in all compartments, with and without N. tenuis, but T. absoluta reached a lower absolute peak density in compartments with N. tenuis (29.1 ± 8.2 larvae per leaf) than in those without them (44.5 ± 19.4 larvae per leaf). The peak numbers of larvae of T. absoluta did not differ on the plants initially infested with 0.2 or 2 larvae. Nesidiocoris tenuis reached a maximum of 1.9 ± 0.43 and 3.0 ± 0.4 individuals per leaf in compartments in which low and high numbers of T. absoluta were initially introduced, respectively. The yield of tomatoes was higher in the treatments with N. tenuis than in those without, but the percentage of damaged fruit (> 50%) was similar. The slow numerical response of N. tenuis might have been due, among other things, to the poor establishment of this mirid due to the scarcity of prey. N. tenuis densities of about 0.2 individuals per leaf during the linear population growth phase of T. absoluta (0.5 to 3 larvae per leaf) did not prevent outbreaks. |
Consequence of the transformation of a primeval forest into a managed forest for carabid beetles (Coleoptera: Carabidae) - a case study from Białowieża (Poland)Jarosław SKŁODOWSKIEur. J. Entomol. 111 (5): 639-648, 2014 | DOI: 10.14411/eje.2014.088 A comparison was made of the number of species, species diversity and ecological traits of carabid beetle (Coleoptera: Carabidae) assemblages inhabiting Białowieża Primeval Forest (National Park) and adjacent managed Białowieża forest planted following clear-cutting of the primeval forest 80 years ago. Five pitfall traps were set in each plot in the primeval and managed forests in areas that differed in terms of humidity and soil fertility. The first hypothesis tested was that the type of stand (primeval vs. managed) has a greater effect on species diversity and life history traits of carabid assemblages than soil fertility or humidity. The second hypothesis tested was that a similar hierarchy of these factors affects the occurrence of particular species. It was demonstrated that the number of species in the primeval and managed forest sites did not differ significantly, but that mesic stands within these forests were more species-rich than boggy stands. However, the Shannon index for carabids was higher for the primeval stands. More species of carabids were recorded in the boggy primeval forest than boggy managed forest. The number of species was also higher in highly fertile than less fertile stands. These results indicate that the significant differences in the patterns of ecological traits among the assemblages studied depended mainly on humidity. This indicates the managed forest that was planted where a primeval stand was clear felled 80 years ago is a good quality habitat, which is a strong argument for protecting these stands. |