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Distinct barcodes for the Cereal leaf beetles Oulema melanopus and Oulema duftschmidi (Coleoptera: Chrysomelidae), two syntopical sibling speciesOriginal articleJulie LEROY, Jean-David CHAPELIN-VISCARDI, Guénaëlle GENSON, Julien HARAN, Éric PIERRE, Jean-Claude STREITOEur. J. Entomol. 117: 490-503, 2020 | DOI: 10.14411/eje.2020.052 Oulema melanopus (Linnaeus, 1758) and Oulema duftschmidi (Redtenbacher, 1874) (Coleoptera: Chrysomelidae) are two native West Palaearctic species developing on various cultivated and wild grasses. Along with O. obscura they are considered to be secondary pests of cereal crops. However, local outbreaks have been recorded recently and their status as secondary pests may evolve, especially as the use of broad-spectrum insecticides is now greatly reduced. Oulema melanopus and O. duftschmidi are considered to be sibling species. They are morphologically very close and difficult to distinguish from each other, which makes it difficult to study them. We tested the reliability of the standard barcode fragment (COI) for distinguishing between these species. A total of 92 samples of the two species, covering the majority of their natural range, was sequenced for the barcode fragment and inter- and intraspecific genetic distances were estimated. Our results confirm those of Bezdìk & Baselga (2015, Acta Entomol. Mus. Nat. Prag. 55: 273-304) in that this marker cannot differentiate between all the species of the Oulema melanopus complex, which in the Mediterranean basin contains several described and possibly some undescribed cryptic species. However, this marker may be useful in an agricultural context in areas where only O. melanopus and O. duftschmidi occur (such as in cereal crops in France) where it can be used to reliably and rapidly separate all stages of these two taxa and can therefore help in studying their ecology and dynamics. |
Time measurement in insect photoperiodism: The role of photophase duration and light intensityIvo Hodek special issueReviewDavid SAUNDERSEur. J. Entomol. 119: 69-76, 2022 | DOI: 10.14411/eje.2022.007 The initial stages of diapause induction - as summer gives way to autumn - involve a process of time measurement in which the duration of daylength (or nightlength) is determined by a photoperiodic 'clock' based upon the circadian system. In many insects so far examined, a photophase of sufficient duration and illuminance resets a photoperiodic oscillator to a constant phase equivalent to the beginning of the 'subjective night' (Circadian time, CT 12 h) whereupon it proceeds to measure nightlength in a clock of the external coincidence type. A possible exception may be found in the linden bug, Pyrrhocoris apterus, which - in laboratory studies using relatively low light intensity - suggests that daylength is measured rather than the night. Earlier studies of photoperiodic responses (pupal diapause induction) in the flesh fly Sarcophaga argyrostoma, however, showed that 'weak' or short light pulses giving rise to Type 1 phase response curves could be converted by increasing light intensity to Type 0 responses that phase set the oscillation to the beginning of the subjective night (CT 12 h) whereupon it could begin to measure the night. Based upon these data it is therefore suggested that the photoperiodic clock in P. apterus might also measure nightlength if the bugs were exposed to photophases of higher irradiance simulating daytime exposure to the light intensity experienced by these diurnally active insects in their natural environment. |
Habitat of Carabus zawadzkii (Coleoptera: Carabidae) in the Eastern CarpathiansOriginal articlePeter GAJDO©, Stanislav DAVID, Oto MAJZLAN, Tomá¹ JÁSZAY, Ján ÈERNECKÝEur. J. Entomol. 119: 285-299, 2022 | DOI: 10.14411/eje.2022.030 This paper provides an analysis of the rare and important Natura 2000 species Carabus zawadzkii in terms of its ecological niche, conservation status and relationship with other Carabus species in carabid assemblages. Published sources are inconsistent in defining the habitats in which this species occurs. Therefore, a large part of this paper is dedicated to identifying the relationship of Carabus zawadzkii with particular non-forest habitats based on field research conducted in 2011-2013. The results revealed an unexpected affinity of this species for non-forest habitats in addition to the know relationship with forest habitats. Further analysis, using additional field data collected over the period 2013-2021, also focused on the assessment of the current conservation status of this rare species. Overall, the population of this species seems stable; however, to improve its conservation status it requires particular management measures. Important conservation measures include periodic extensive mowing of mountain hay meadows. This species' seasonal dynamics provides important information for nature conservationists. It is important to carry out research on this species in May, when it is most active. Presented results provide the most comprehensive overview of the ecological preferences and occurrence of this important and very rare Carpathian species. |
Inoculation of cucumber plants with Beauveria bassiana enhances resistance to Aphis gossypii (Hemiptera: Aphididae) and increases aphid susceptibility to pirimicarbOriginal articleMohammad HOMAYOONZADEH, Mojtaba ESMAEILY, Khalil TALEBI, Hossein ALLAHYARI, Stuart REITZ, J.P. MICHAUDEur. J. Entomol. 119: 1-11, 2022 | DOI: 10.14411/eje.2022.001 The entomopathogen Beauveria bassiana (Bals.) Vuill. (Ascomycota: Hypocreales) can colonize plants endophytically and stimulate the production of secondary plant metabolites with anti-herbivore activities. We assayed the topical virulence of B. bassiana to Aphis gossypii Glover (Hemiptera: Aphididae), the effects of cucumber inoculation with this fungus on plant metabolites, and the physiological consequences for aphids that fed on these plants. Assays were conducted with both the commercial formulation of B. bassiana, 'Naturalis®-L', at the recommended concentration of 1.5 ml / L (yielding a spore concentration of 2.3 × 107 CFU per ml), and with a similar concentration of the isolated fungal strain. Topical application of 0.03 ml of solution per cm2, or 1 × 103 CFU, caused 100% mortality to A. gossypii adults after seven days, whether Naturalis®-L or the isolate alone was used. The fungus grew endophytically into foliage when sprayed on cucumbers at the 2-leaf stage and concentrations of alkaloids, flavonoids, phenols, hydrogen peroxide, and total chlorophyll were higher than in control plants 28 days after inoculation. Malondialdehyde content, plant growth, and total yield were unaffected by B. bassiana inoculation. Aphids fed on B. bassiana-inoculated plants for 24 h had reduced activities of detoxifying enzymes (glutathione-S-transferase, carboxylesterase, and acetylcholinesterase) compared to controls. Activities of digestive enzymes, (lipase, α-amylase, α-glucosidase, and aminopeptidase) were reduced in aphids from inoculated plants, which exhibited higher activities of superoxide dismutase, ascorbate peroxidase, and phenoloxidase, but lower catalase activity. Energy reserves (lipids, protein, and glycogen) were lower in aphids from inoculated plants, and they exhibited reduced fecundity, longevity, and reproductive periods, and a 50% reduction in the LC50 of pirimicarb. Thus, in addition to causing direct pathogenicity, inoculation of plants with B. bassiana negatively impacted A. gossypii physiology and reproductive performance and could usefully complement other strategies for managing cotton aphids on greenhouse cucumber. |
An overview of irritans-mariner transposons in two Mayetiola species (Diptera: Cecidomyiidae)Original articleWiem BEN AMARA, Salma DJEBBI, Dhia BOUKTILA, Mohamed MAKNI, Hanem MAKNI, Maha MEZGHANI-KHEMAKHEMEur. J. Entomol. 114: 379-390, 2017 | DOI: 10.14411/eje.2017.049 Mariner-like elements (MLEs) are widespread Class II transposable elements in insects that are subdivided into several subfamilies. In the current study, we carried out in silico analysis and in vitro experiments to identify MLEs belonging to the irritans subfamily in two cecidomyiid flies, Mayetiola destructor and M. hordei. In silico investigation of M. destructor genome allowed the identification of 25 irritans-like elements, which were mostly defective due to several mutations. These defective forms might be the remnants of active elements that ancestrally invaded the host genome. Structural analyses, including signature motifs and transposase-encoding ORFs, revealed structural heterogeneity and the presence of two full length copies. Five consensuses, reflecting the probable evolutionary groups of these elements, were constructed, based on a similarity matrix. The first consensus (Maymarcons1) belonged to Himar1-like elements reported in other insects, while the remaining four (Maymarcons2 to 5) seemed to be more specific to Cecidomyiidae. Moreover, the presence of elements belonging to the Maymarcons4 group was ascertained by PCR amplification, in both Mayetiola species, and was further identified in the Transcriptome Shotgun Assembly (TSA) of the orange fly, Sitodiplosis mosellana (Cecidomyiidae), suggesting the existence of irritans elements within the Cecidomyiidae, which were derived from an ancestral species by vertical transmission during speciation. On the other hand, consensuses that are specific to M. destructor could be derived from a more recent invasion. This study suggests that both M. destructor and M. hordei genomes have been invaded by irritans elements many times with at least two different evolutionary histories. |
Functional responses and intraspecific competition in the ladybird Harmonia axyridis (Coleoptera: Coccinellidae) provided with Melanaphis sacchari (Homoptera: Aphididae) as preyOriginal articlePengxiang WU, Jing ZHANG, Muhammad HASEEB, Shuo YAN, Lambert KANGA, Runzhi ZHANGEur. J. Entomol. 115: 232-241, 2018 | DOI: 10.14411/eje.2018.022 Functional responses at each developmental stage of predators and intraspecific competition associated with direct interactions among them provide insights into developing biological control strategies for pests. The functional responses of Harmonia axyridis (Pallas) at each developmental stage of Melanaphis sacchari (Zehntner) and intraspecific competition among predators were evaluated under laboratory conditions. The results showed that all stages of H. axyridis displayed a type II functional response to M. sacchari. Based on Holling's disc equation, the instantaneous searching rates were highest (a) and handling time was shortest (Th) of fourth instar larvae (a = 0.8818; Th = 3.9 min) and female adults (a = 0.9881; Th = 3.0 min) at larval and adult stages, respectively. The coefficients of mutual interference (m) assessed by the intraspecific competition equation were higher for fourth instar larvae (m = 0.4764) and female adults (m = 0.4183). The present study indicates that fourth instar and female adult were more effective stages of H. axyridis in the context of biological control but suitable predator densities need to be considered before natural enemy release. |
Early successional colonizers both facilitate and inhibit the late successional colonizers in communities of dung-inhabiting insectsOriginal articleFrantisek X.J. SLADECEK, Simon T. SEGAR, Martin KONVICKAEur. J. Entomol. 118: 240-249, 2021 | DOI: 10.14411/eje.2021.025 The influence of early arriving species on the establishment and activity of later ones (the priority effect) is a key issue in ecological succession. Priority effects have been extensively studied in communities subject to autotrophic succession (plants, sessile animals), but only sporadically studied in communities subject to heterotrophic succession (e.g. dung or carrion inhabiting communities). We studied the influence of early successional colonizers on late successional colonizers by manipulating the successional processes in cow dung pats via delaying, and thus lowering, colonization by early successional insects. The decreased activity of early successional insects did not affect the species richness of late successional insects, but it did lead to increased abundance of colonizers. Late successional coprophagous beetles were facilitated by early successional species while larvae of late successional coprophagous flies were inhibited, presumably, by the larvae of early successional flies. We therefore propose that both facilitation and inhibition have a role to play in the heterotrophic succession of coprophilous insects. In addition, facilitation and inhibition among taxa seems to reflect their evolutionary relationships, with facilitation being prominent between phylogenetically distant lineages (early successional Diptera and late successional Coleoptera), and inhibition being more common between closely related lineages (early vs. late successional Diptera). These patterns are strikingly reminiscent of the situation in the autotrophic succession of plants. |
Infection-induced molecular pattern recognition proteins in larvae of Protaetia brevitarsis seulensis (Coleoptera: Cetoniidae)Original articleKyeongrin BANG, Jiae LEE, Sejung HWANG, Youngwoo CHO, Jangwoo PARK, Saeyoull CHOEur. J. Entomol. 119: 77-84, 2022 | DOI: 10.14411/eje.2022.008 We cloned and sequenced full-length peptidoglycan recognition protein (PGRP)-like cDNAs, named PS PGRP-SA(a)-like, PS PGRP-SA(b)-like, PS PGRP-SB1-like and PS PGRP-SC-like, from Protaetia brevitarsis seulensis. The amino acid sequences of PS PGRPs share 32.03-47.93% homology with those of PGRP family members in insects and mammals, including humans. We identified a conserved consensus sequence for amidase activity (His; H-Tyr; Y-His; H-Thr; T-Cys; C) and residues for binding peptidoglycan (PGN), one of the major bacterial cell wall components, including Asp (D) and Phe (F) for Lys-type PGN; and Gly(G), Trp (W) and Arg (R) for DAP-type PGN. The topological structures of PS PGRP-SA(a)-like, PS PGRP-SA(b)-like and PS PGRP-SC-like proteins are structurally similar to those of Drosophila melanogaster PGRP-SA, which has three α-helices and six β-strands. The β-strands are located in a central region and helix α1 on the back and peripheral α2 and α3 helices are on the front. The three α-helices and six β-strands are also present in PS PGRP-SB1-like, but the topological structure differs from that of typical PGRP. Significantly increased levels of PS PGRP-SA (a)-like and PS PGRP-SA (b)-like mRNA were recorded when Gram-positive bacteria or yeast cells were injected into larvae. PS PGRP-SB1-like mRNA levels were up-regulated by infection by all three pathogens; however, expression of PS PGRP-SC-like mRNA was increased 20- or 30-fold only shortly after injection with Gram-negative bacteria. |
Contribution of a DNA barcode to an assessment of the specificity of ant taxa (Hymenoptera: Formicidae) on CorsicaOriginal articleRumsaïs BLATRIX, Clément AUBERT, Thibaud DECAËNS, Cyril BERQUIER, Marie-Cécile ANDREI-RUIZ, Christophe GALKOWSKIEur. J. Entomol. 117: 420-429, 2020 | DOI: 10.14411/eje.2020.046 We used the COI marker, the most popular DNA barcode for the animal kingdom, to assess the taxonomic status of Corsican populations of eight groups of species of ants that occur both on Corsica and the European mainland. (i) In two groups, we detected no genetic differentiation between Corsica and the continent. Absence of differentiation across varieties of Aphaenogaster spinosa within Corsica confirm current synonymies. (ii) In four groups, we detected strong genetic differentiation between Corsica and the continent, confirming recent taxonomic studies based on morphology for three of these groups. For the fourth group, we propose that the status of Corsican populations be raised from sub-species to species: Temnothorax cordieri stat. rev. (iii) In one group, the genetic differentiation and morphological differences do not support splitting and as a consequence we propose to accept the previous synonymy Temnothorax tuberum = Temnothorax melanocephalus. (iv) In Myrmica scabrinodis and Myrmica spinosior, COI sequence information is largely inconsistent with morphology and geography, not only on Corsica but also on the mainland, and should not be used to support taxonomic decisions. Although the use of COI has drawbacks, it is globally consistent with morphology and can be used to complement morphological ant taxonomy. We provide an updated checklist of ants of Corsica. |
The circadian clock gene (Clock) regulates photoperiodic time measurement and its downstream process determining maternal induction of embryonic diapause in a cricketIvo Hodek special issueOriginal articleShin G. GOTO, Masatoshi NAGATAEur. J. Entomol. 119: 12-22, 2022 | DOI: 10.14411/eje.2022.002 In response to short days in autumn, most temperate multivoltine insects enter diapause, a state in which development or reproduction is suppressed or arrested, which serves to coordinate their development and physiology (or that of offspring) with annual changes in the environment (i.e. photoperiodism). This response is mediated by a measurement of time based on photoperiod (photoperiodic time measurement), which is thought to be regulated by a circadian clock. However, some studies also demonstrate the involvement of the circadian clock in an output process that generates phenotypes associated with diapause. To gain further insight into this, we silenced the Clock (Clk) gene, the main regulator of the circadian clock, in the band-legged ground cricket Dianemobius nigrofasciatus (Orthoptera: Trigonidiidae). Silencing the Clk gene using RNA interference (Clk RNAi) in female crickets resulted in abnormal circadian rhythms under constant darkness and light-dark conditions, thereby indicating the central role of this gene in the circadian clock mechanism. Clk RNAi females exhibited long-day oviposition behaviour, even when reared under short-day conditions, thereby indicating the involvement of Clk in photoperiodic time measurement. In addition, Clk RNAi females immediately laid non-diapause-type eggs, which was not recorded in control females under either short-day or long-day conditions and cannot be explained in terms of dysfunction of photoperiodic time measurement. Accordingly, we speculate that Clk could also be involved in a downstream process that results in the laying of diapause-type eggs. |
Six new species of the subgenus Habronychus (Habronychus) (Coleoptera: Cantharidae) from the Oriental region, with key to speciesOriginal articleShujuan GE, Haoyu LIU, Xingke YANG, Yuxia YANGEur. J. Entomol. 119: 201-214, 2022 | DOI: 10.14411/eje.2022.022 Six new species of Habronychus (Habronychus) Wittmer, 1981 are described, including H. (H.) laticeps Y. Yang, Ge & X. Yang, sp. n., H. (H.) honestus Y. Yang, Ge & X. Yang, sp. n., H. (H.) crassatus Y. Yang, Ge & X. Yang, sp. n. and H. (H.) tengchongensis Y. Yang, Ge & X. Yang, sp. n. from China, and H. (H.) longiplatus Y. Yang, Ge & Liu, sp. n. and H. (H.) trianguliceps Y. Yang, Ge & Liu, sp. n. from Vietnam. In addition, a previously known species, H. (H.) parallelicollis (Pic, 1921), is redescribed. The above species are illustrated with habitus photographs, aedeagi, abdominal sternites VIII and internal genitalia of females. Key for identification of the species of this subgenus worldwide is provided. |
The role of 10-hydroxy-Δ2-decenoic acid in the formation of fibrils of the major royal jelly protein 1/apisimin/24-methylenecholesterol complex isolated from honey bee (Apis mellifera) royal jellyOriginal articleAnja BUTTSTEDTEur. J. Entomol. 119: 448-453, 2022 | DOI: 10.14411/eje.2022.047 Queen larvae of the honey bee (Apis mellifera) are fed with royal jelly, a glandular secretion produced by the hypopharyngeal and mandibular glands of worker honey bees. The necessary consistency of royal jelly is dependent on a protein-sterol complex (MRJP14/apisimin4/24MC8). At low pH, this complex forms fibrillar structures, which increase the viscosity of royal jelly. While the proteins in this complex are produced in the hypopharyngeal gland, the low pH is achieved by the secretion of the mandibular gland, which contains fatty acids. It is shown for the first time that fibril formation of MRJP14/apisimin4/24MC8 is not only induced by low pH via a buffer system, but also by the addition of the major fatty acid 10-hydroxy-Δ2-decenoic acid (10-HDA) of the mandibular gland secretion. This result further substantiates that fibril formation of the MRJP14/apisimin4/24MC8 complex only occurs after mixing the hypopharyngeal and mandibular gland secretions. |
Screening for stable internal reference genes for quantitative PCR analysis of Wolbachia-host interactions in whitefly Bemisia tabaci (Homoptera: Aleyrodidae)Original articleXin-Chao LIU, Zheng-Xi LIEur. J. Entomol. 116: 402, 2019 | DOI: 10.14411/eje.2019.041 Stable reference genes (RGs) determine the reliability of quantitative polymerase chain reaction (qPCR) analyses and it is recommended that different reference genes are used for different types of DNA and tissues. The present study aimed to screen for stable RGs for the qPCR analysis of the immune responses of the whitefly Bemisia tabaci to the Wolbachia wMel strain from Drosophila melanogaster. A total of eight candidate RGs were evaluated using five different methods, i.e., Coefficient of Variation analysis, GeNorm, NormFinder, BestKeeper and ΔCt. The stability of these RGs was assessed for both genomic DNA (gDNA) and complementary DNA (cDNA). The results indicate that β-actin (Actin) and elongation factor 1 alpha (EF-1α) were the most stable RGs for gDNA, whereas 18S rRNA (18S) and glyceraldehyde phosphate dehydrogenase (GAPDH) were the least stable; in contrast, Actin and GAPDH were the most stable for cDNA, whereas RPL29 and ATPase were the least stable. The effectiveness of the most stable RGs was then validated against the least stable using qPCR analysis of the titre of wMel (gDNA) and the transcriptional responses of the antimicrobial peptide Alo-3-like and the phosphatidylinositol-bisphosphate 3-kinase catalytic subunit delta isoform (cDNA) to wMel transfection. The results support the notion that reliable RGs are essential for a qPCR analysis of samples of both gDNA and cDNA. |
Functional responses of two predatory bugs (Hemiptera: Anthocoridae) to changes in the abundance of Tetranychus urticae (Acari: Tetranychidae) and Bemisia tabaci (Hemiptera: Aleyrodidae)Original articleSerkan PEHLİVAN, Tuğcan ALINÇ, Tange Denis ACHIRI, Ekrem ATAKANEur. J. Entomol. 117: 49-55, 2020 | DOI: 10.14411/eje.2020.005 Orius spp. (Hemiptera: Anthocoridae) is well-known genus of generalist predators, which feed on numerous pest insects and mites infesting crops. In this study, the functional responses of the predatory bugs, Orius laevigatus (Fieber) and Orius vicinus (Ribaut), to different densities of the eggs of the whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and red spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), were determined under laboratory conditions. Different numbers of eggs (2, 4, 6, 8, 16, 32, 64 and 128) of both species of prey were offered to females of the above predators for 24-h in a controlled environment of 25 ± 1°C, 60 ± 10% RH and under a 16L : 8D photoperiod. The parameters of the functional responses were assessed using Holling's Disc Equation. Both predators showed a Type II response to both prey. The attack rates (a) and handling times (Th) of the predators were computed for spider mites eggs: O. laevigatus (a: 0.972, Th: 0.007) and O. vicinus (a: 1.113, Th: 0.005), and whitefly eggs: O. laevigatus (a: 1.022, Th: 0.002) and O. vicinus (a: 0.772 Th: 0.006). Furthermore, the average number of B. tabaci eggs consumed by O. laevigatus females was greater than by those of O. vicinus. In contrast, O. vicinus was a more efficient predator of T. urticae eggs than O. laevigatus. Consequently, these results indicate that together these predators might be effective biological control agents in regulating populations of B. tabaci and T. urticae in agricultural ecosystems. |
Screening of immune-related genes against bacterial infection in Ostrinia furnacalis (Lepidoptera: Crambidae)Original articleWan ZHOU, Zengxia WANG, Baohong HUANGEur. J. Entomol. 119: 388-397, 2022 | DOI: 10.14411/eje.2022.040 Ostrinia furnacalis Guenée is an important pest of maize. The current use of microbial agents to control O. furnacalis have been relatively successful. However, upon infestation with microorganisms, O. furnacalis initiates an innate immune response to defend itself against foreign invaders. Therefore, understanding the immune mechanisms in O. furnacalis is important to ensure a more efficient use of microbial agents for the control of this pest. In the present study, a gram-positive bacterium, Staphylococcus aureus, and a gram-negative bacterium, Escherichia coli, were used to induce an immune response in O. furnacalis. Transcriptomic sequencing was then used to screen for genes that were significantly differentially expressed after microbial induction and sequence comparison and phylogenetic analysis to identify immune-related genes the expression of which was significantly induced. The results show a large number of genes were differentially expressed in O. furnacalis after microbial induction, the majority of which were immune-related genes. The expression of some immune-related genes such as those encoding antimicrobial peptides, peptidoglycan recognition proteins and serine protease inhibitors were strongly induced. Overall, our study increases the understanding of the mechanism of the innate immune response in O. furnacalis and provides a theoretical basis for better biological control using microbial agents. |
Invasive brown marmorated stink bug (Hemiptera: Pentatomidae) facilitates feeding of European wasps and ants (Hymenoptera: Vespidae, Formicidae) on plant exudatesOriginal articleDavide SCACCINI, Alberto POZZEBONEur. J. Entomol. 118: 24-30, 2021 | DOI: 10.14411/eje.2021.003 The brown marmorated stink bug, Halyomorpha halys, is a polyphagous species from eastern Asia, which has spread to America and Europe where it damages many crops. In recently colonized areas, facilitative interactions between H. halys and native insects are poorly investigated. In this study, we report for the first time facilitation of native wasp and ant feeding by H. halys in Europe. The facilitation was related to the outflow of plant exudates caused by H. halys feeding on manna ash trees, where they have aggregated in response to an aggregation pheromone, which then attracted species of Hymenoptera to the infested trees. Trees other than manna ash were not involved in the facilitation between these two taxa. The species that frequently visited infested manna ash were Polistes dominula, Vespa crabro, Formica (Serviformica) cunicularia and Lasius emarginatus, while Polistes cf. nimpha, Vespula germanica, Crematogaster scutellaris and Tapinoma subboreale were occasional visitors. The numbers of wasps and ants feeding on plant exudates differed at different times in a day, with more Hymenoptera foraging in the afternoon, when more H. halys individuals were actively feeding. Facilitative interactions, such as those recorded in this study, are important for furthering our understanding of the ecology of invasive species in terms of creating sources of food for native organisms. |
DNA barcoding reveals long-term speciation processes in subspecies of the Melipona (Michmelia) seminigra complex (Hymenoptera: Apidae)Original articleIzaura Bezerra FRANCINI, João Marcos Guimarães CAPURUCHO, Antônio Saulo Cunha MACHADO, Carlos Gustavo NUNES-SILVA, Jacqueline Da Silva BATISTA, Luciano COSTA, Gislene Almeida CARVALHO-ZILSEEur. J. Entomol. 119: 309-317, 2022 | DOI: 10.14411/eje.2022.032 The stingless bee Melipona (Michmelia) seminigra Friese is a polytypic species widely distributed in Brazilian Amazon and Bolivia. Seven subspecies are recognized, four are described, which inhabit mutually exclusive areas in the Amazon basin, although zones of hybridization are recorded. The three other subspecies, despite being recognized by taxonomists are undescribed. Melipona seminigra is a good honey-producer and an important pollinator of native flora and crops. Partial DNA sequence of cytochrome c oxidase subunit 1 (COI) mitochondrial gene (526 bp) was used to identify the four described subspecies of M. seminigra (M. s. abunensis, M. s. merrillae, M. s. pernigra, M. s. seminigra) and two other possible subspecies (M. s. ssp1 and M. s. ssp2). We added public data (sequences of ten other Melipona species) of the same subgenera and carried out phylogenetic analyses. The aim was to evaluate if subspecies in the M. seminigra complex could be delimited using COI and measure the genetic distances between them. Our results revealed that the genetic distances between subspecies of M. seminigra ranged from 0.4 to 2.7% (average 1.80 ± 0.47) and among Melipona species from 0.2 to 2.9% (average 2.13 ± 0.5). The average haplotype diversity was 0.8770 ± 0.0140 and average nucleotide diversity 0.0166 ± 0.0004. Phylogenetic and clustering analysis revealed well delimited clusters for subspecies of M. seminigra and that the inter subspecies divergences are similar to inter species divergence. Our findings indicate that the COI gene can be used for delimiting subspecies of M. seminigra. |
Evolutionary and ecological signals in Wolbachia-beetle relationships: A reviewReview£ukasz KAJTOCHEur. J. Entomol. 119: 215-226, 2022 | DOI: 10.14411/eje.2022.023 Intracellular bacteria of the genus Wolbachia are the most abundant endosymbionts infecting many arthropods, with Coleoptera being the most diverse hosts in terms of taxonomy and ecology. There has been great progress in studies on the relations between Wolbachia and beetles, however, only some of the research details the consequences of infection. In this review, I summarise the knowledge on the evolutionary relations or ecological associations between Wolbachia and its beetle hosts. These bacteria often cause cytoplasmic incompatibility in the infected hosts and are responsible for a selective sweep of the mitochondrial genomes in some beetles. Wolbachia can manipulate the sex ratio or reproduction of some species of beetles, however, it does not induce parthenogenesis, with the possible rare exception of some Naupactini. Proof of the co-evolution of Wolbachia with beetles is missing, but some aquatic groups seem to be prone to co-speciation, unlike terrestrial taxa. On the other hand, there is a growing number of studies indicating or proving horizontal transmission of Wolbachia among beetle hosts, mostly via common host plants or the foraging substrate (such as dung). Wolbachia is not alone in infecting beetles as other endosymbiotic bacteria occur in beetles (Rickettsia, Spiroplasma, Cardinium, Arsenophorus), which have often been reported as interchangeable, suggesting the infection by various bacteria is dynamic. Nonetheless, there are still many issues associated with Wolbachia that are not yet been described in beetles (like the provision of nutrition or protection against pathogens) and high-throughput sequencing should be used to improve our understanding of Wolbachia-Coleoptera relations. |
Oviposition preference and olfactory response of Diaphania indica (Lepidoptera: Pyralidae) to volatiles of uninfested and infested cucurbitaceous host plantsOriginal articleAmin MOGHBELI GHARAEI, Mahdi ZIAADDINI, Mohammad Amin JALALI, Brigitte FREROTEur. J. Entomol. 116: 392-401, 2019 | DOI: 10.14411/eje.2019.040 The cucumber moth, Diaphania indica (Saunders) (Lepidoptera: Pyralidae), is a major pest of cucurbitaceous plants. The oviposition preference and olfactory response of larvae, mated and unmated male and female adults to volatiles emanating from uninfested and infested plants of four species of cucurbitaceous host plants and odours of conspecifics were recorded. Also the role of experience in the host finding behaviour of D. indica was evaluated. The experiments were done using a wind tunnel, olfactometer attraction assays and oviposition bioassays. The results reveal that fewer eggs were laid on infested plants than on uninfested plants. Females significantly preferred cucumber over squash, melon and watermelon. Cucurbitaceous plants elicited adults of D. indica to fly upwind followed by landing on the plants. The effect of experience on the olfactory preference of D. indica was dependent on the host plant. Females that had experience of cucumber, squash and melon plants were significantly attracted to the same plant, but not in the case of watermelon. Larvae of this pest were attracted only to volatiles of uninfested cucumber, squash and melon, whereas volatiles of conspecifics, infested plants and intact watermelon did not attract larvae. This study is an initial attempt to investigate the role of volatile infochemicals in the host-finding behaviour of D. indica. These results provide baseline information for the development of new control strategies against D. indica. |
Sexual dimorphism and phylogenetic position of Chilodendron (Coleoptera: Curculionidae: Scolytinae) - a long isolated lineage endemic to MadagascarOriginal articleBjarte H. JORDALEur. J. Entomol. 119: 152-158, 2022 | DOI: 10.14411/eje.2022.017 Chilodendron Schedl, 1953 is resurrected as a valid genus based on Chilodendron planicolle Schedl, 1953. This is the only representative of the tribe Hylesinini Erichson, 1836 found on Madagascar and a molecular phylogenetic analysis of several genes supports a position separate from Hylesinopsis Eggers, 1920 and other putatively close relatives. It is likely that Chilodendron is the oldest living lineage of bark beetles on Madagascar and possibly originated in the late Cretaceous not long after the separation of Madagascar from the Indian subcontinent. |
Oviposition-site preferences of a declining butterfly Erebia medusa (Lepidoptera: Satyrinae) in nutrient-poor grasslandsGregor STUHLDREHER, Thomas FARTMANNEur. J. Entomol. 112 (3): 493-499, 2015 | DOI: 10.14411/eje.2015.067 Butterflies belong to one of the most intensively studied invertebrate groups. However, detailed information on the larval ecology is still lacking in many species. This is especially true for the grass-feeding subfamily Satyrinae, to which our study species, the Woodland Ringlet (Erebia medusa Fabricius, 1787), belongs. At the habitat level, E. medusa exhibits a clear preference for abandoned grasslands with litter accumulation. In this study, we assessed the host-plant and oviposition preferences of E. medusa at the microhabitat level, i.e., within occupied habitat patches, in the Diemel Valley (Central Germany). Only two species of grass, Festuca ovina agg. and F. rubra agg., were systematically used for oviposition. Egg density was positively correlated with patchiness of herb layer, potential daily length of sunshine, and abandonment. However, the explanatory power of these parameters was low. We attribute this primarily to an ample supply of host plants growing under suitable conditions in the occupied habitat patches of E. medusa. The positive effect of abandonment is probably due to the fact that the average height of oviposition sites of E. medusa is greater than in most other satyrine species, which renders the eggs more vulnerable to mechanical disturbance. Moreover, thick layers of litter, which develop after the cessation of grazing or mowing, might be important as they modify the microclimate at the locations of the immature stages. |
The DNA barcoding project on German Diptera: An appreciative and critical analysis with four suggestions for improving the development and reliability of DNA-based identificationOriginal articleMarion KOTRBAEur. J. Entomol. 117: 315-327, 2020 | DOI: 10.14411/eje.2020.037 The progress in constructing a DNA barcode library for German Diptera as published by Morinière et al. (2019, Mol. Ecol. Resour. 19: 900-928) is appraised from a dipterists' perspective. The coverage of the diversity of German Diptera in terms of barcode index numbers (BINs) and identified barcodes is analysed and visualized in simple diagrams. The influence of the project setup, methodology and/or systematic effects on the emerging numbers and trends is elucidated and extensively discussed. In addition, the documentation on the species identification methods in the database is assessed. Based on this evaluation, four ways for improving the future development, utility and reliability of this DNA database and similar projects in general are identified: (1) Sample the collections of experts. This results in a greater and more reliable coverage within a limited time frame, as opposed to random collecting and relying on a posteriori identification. (2) Give priority to medically, agriculturally or ecologically important families. Addressing these gaps will meet the most pressing needs of the community and serve as a good advertisement for the usefulness and wide applicability of the DNA barcode library. (3) Allocate resources to recruiting established experts as opposed to trainees. The fact that half of the recovered BINs remained unidentified mostly results from the insufficient involvement of experts (and expert time). (4) Appropriately document the morphological identifications by experts in the database. This will allow to assess the reliability of DNA-based identifications and to prioritize conflicting identifications within a BIN accordingly. |
Ecological niche modelling of species of the rose gall wasp Diplolepis (Hymenoptera: Cynipidae) on the Iberian PeninsulaOriginal articleSara SARDÓN-GUTIÉRREZ, Diego GIL-TAPETADO, José F. GÓMEZ, José L. NIEVES-ALDREYEur. J. Entomol. 118: 31-45, 2021 | DOI: 10.14411/eje.2021.004 Diplolepis (Hymenoptera: Cynipidae) are gall wasps that induce conspicuous galls on Rosa spp. (Rosaceae). These species are distributed globally and in Europe some are especially common and are founder organisms of biological communities composed of different insects. However, the ecological niches of these species have not been studied in detail. We modelled the potential distributions of these species using the locations of the galls of the four most abundant species of Diplolepis on the Iberian Peninsula (Diplolepis mayri, Diplolepis rosae, Diplolepis eglanteriae and Diplolepis nervosa, the galls of latter two are indistinguishable) using four different algorithms and identified the resulting consensus for the species. We compared the potential distributions of these species, considering their spatial complementarity and the distributions of their host plants. We found that D. mayri and D. eglanteriae/nervosa have complementary distributions on the Iberian Peninsula. The former species is found in the Mediterranean region, while D. eglanteriae and D. nervosa are distributed mainly in the Eurosiberian region. Diplolepis rosae has the widest distribution on the Iberian Peninsula. Our models constitute the first effort to identify suitable areas for species of Diplolepis species on the Iberian Peninsula and could be useful for understanding the evolutionary ecology of these species throughout their distribution in the western Palearctic. |
Biogeography and habitat preferences of red wood ants of the Formica rufa group (Hymenoptera: Formicidae) in Finland, based on citizen science dataOriginal articleJouni SORVARIEur. J. Entomol. 119: 92-98, 2022 | DOI: 10.14411/eje.2022.010 Red wood ants (RWA) of the Formica rufa group are ecosystem engineers and important species in boreal and temperate forests. However, the permanent and temporal loss of forest habitats is a serious threat to their existence and is likely to increase with climate change. Due to the current threat of losing species, quick actions are needed. Reported here is the biogeography, relative abundance and habitat preferences of five species of RWA in Finland based on citizen science data. Species that occur in the lowlands of the Alps also occur throughout the southern parts of Finland. Only two of the five species, F. aquilonia Yarrow, 1955 and F. lugubris Zetterstedt, 1838, were common throughout the country, including northern Lapland. As their name suggests, RWAs occur mostly in forests and forest edges, but they also sometimes inhabit open or semi-open yards, mires and meadows. The most forest-specialist species is F. aquilonia and the least F. rufa Linnaeus, 1761. Surprisingly, the meadow wood ant F. pratensis Retzius, 1783 is the second most forest dwelling species, however, its preference for forest edges is clearly higher than for forest interiors. Based on current data, F. rufa may be the most tolerant of living close to buildings as its relative abundance in yards was much higher than that of the other species. The data obtained on distributions and relative abundances could be compared in the future with the results of similar surveys to detect changes in species distributions, relative abundances and habitat preferences. |
Diversity of ant assemblages (Hymenoptera: Formicidae) in an urban environment in Cameroon during and after colonization of the area by Wasmannia auropunctataOriginal articlePaul Serge MBENOUN MASSE, Maurice TINDO, Champlain DJIÉTO-LORDON, Ruth MONY, Martin KENNEEur. J. Entomol. 116: 461-467, 2019 | DOI: 10.14411/eje.2019.047 Invasive species disrupt the organization and functioning of many ant communities. Little is known about ant assemblages formerly in areas invaded by the little fire ant. In this study, we surveyed the same areas and compared the ant communities there when an invasive species first colonized the areas and 10 years later, using the same methodology (quadrat and baiting). A total of 83,299 worker ants from 17 species or morphospecies, in 4 subfamilies and 10 genera were recorded in the two periods sampled. Seven ant species were found to co-occur with W. auropunctata while 12 species were collected in the same area 10 years later, with no W. auropunctata recorded in any of the traps. In the absence of W. auropunctata, the number and diversity of ant species increased and the ant communities were dominated by the African big-headed ant, Pheidole megacephala. Our findings indicate that the disappearance of W. auropunctata is probably related to population increases in P. megacephala associated with dramatic changes in landscape. Further studies at other invaded locations should be carried out in order to reveal the generality of these patterns throughout this country. |
Oxymorus (Coleoptera: Curculionidae: Entiminae: Oosomini), a new genus with nine new species from South AfricaOriginal articleRoman BOROVEC, Massimo MEREGALLIEur. J. Entomol. 117: 442-462, 2020 | DOI: 10.14411/eje.2020.048 A new genus Oxymorus Borovec & Meregalli gen. n., belonging to the tribe Oosomini Lacordaire, 1863 of the curculionid subfamily Entiminae, is described. It includes nine new species, all from South Africa: Oxymorus uitkyk sp. n., type species, O. antennalis sp. n., O. johnprinei sp. n., O. minor sp. n., O. obesus sp. n., O. oculatus sp. n., O. rikae sp. n., O. strictifrons sp. n. and O. sulcaticollis sp. n. All species are illustrated and keyed. |
Temporal and climatic variation in the colour forms of Adalia bipunctata and Harmonia axyridis (Coleoptera: Coccinellidae) populations in the United KingdomIvo Hodek special issueOriginal articleAyman ASIRI, Chris FOSTEREur. J. Entomol. 119: 250-259, 2022 | DOI: 10.14411/eje.2022.027 Colour form polymorphism in Adalia bipunctata (Linnaeus, 1785) and Harmonia axyridis (Pallas, 1773) has been extensively studied in the past. Climate, season, and region are known to influence the colour form frequencies of these species, however, this effect is region specific, and the response of populations has changed over time. Here, 5862 photographic records from the UK Ladybird Survey from 2013-2017 were used to assess the geographic variation in colour form frequency (melanic versus non-melanic) of A. bipunctata and H. axyridis across the United Kingdom (UK) in relation to climate and season. Climate data from the UK Met Office were used to determine the effect of climate on melanic form. Seasonal variation in melanic form was observed in H. axyridis but not A. bipunctata. For H. axyridis, the probability of being melanic decreased in areas with higher annual sunlight hours. In A. bipunctata, there was an interaction between sunlight hours and rainfall. In areas with low rainfall, the probability of being melanic was negatively correlated with sunlight hours. Where rainfall was high, the probability of being melanic was positively correlated with sunlight hours. These findings highlight the role of climate in determining the proportion of colour forms in UK populations of A. bipunctata and H. axyridis. Furthermore, the results support the hypothesis that seasonal variation in melanism does not occur in A. bipunctata populations with a low overall proportion of melanics. |
Current and predicted distribution of the rare and threatened beetle Bolbelasmus (Bolbelasmus) unicornis (Coleoptera: Geotrupidae) in SerbiaOriginal articleSreæko ÆURÈIÆ, Dragan PAVIÆEVIÆ, Dejan RADOVIÆ, Nikola VESOVIÆ, Rostislav BEKCHIEV, Nina ÆURÈIÆ, Borislav GUÉORGUIEVEur. J. Entomol. 116: 413-424, 2019 | DOI: 10.14411/eje.2019.042 Bolbelasmus (Bolbelasmus) unicornis (Schrank, 1789) (Coleoptera: Geotrupidae) is a rare and threatened beetle distributed mostly in Central, Eastern and Southeast Europe. As a species of special conservation significance it is included in Annexes II and IV of the Habitat Directive of the European Union. Several new records of this species documented using light traps and soil sampling were recently reported in Serbia (the central part of the Balkan Peninsula). In this paper we present and discuss the current distribution of this species in the region studied based on GIS occurrence data. The distribution is mapped and values of environmental variables within this beetle's range are quantified using GIS technology. In addition, we predict its potential range in Serbia using a model based on the current distribution of this beetle, environmental variables and distribution of its food source. |
Using sentinel prey to assess predation pressure from terrestrial predators in water-filled tree holesOriginal articleMartin M. GOSSNER, Elena GAZZEA, Valeriia DIEDUS, Marlotte JONKER, Mykola YAREMCHUKEur. J. Entomol. 117: 226-234, 2020 | DOI: 10.14411/eje.2020.024 Tree-related microhabitats are important for forest biodiversity. Water-filled tree holes are one such microhabitat and can be abundant in temperate forests. The arthropod community in this microhabitat not only contribute to forest biodiversity but also provides food for terrestrial predators such as arthropods, small mammals and birds. The extent of the threat of attack from terrestrial predators on insect larvae in this microhabitat, however, is poorly known. To measure predation in this microhabitat, we produced fake prey resembling insect larvae using white plasticine and exposed them at the aquatic-terrestrial habitat interface. We recorded: (1) which predators attacked the fake larvae, (2) the predation probability on the fake larvae after two days and after two weeks and (3) whether predation probability on fake larvae differed between managed and unmanaged forest zones in one of the last primeval beech forests, the Uholka division of the Carpathian Biosphere Reserve in the Ukrainian Carpathians. By addressing these questions, we aimed to quantify the predation pressure of terrestrial predators on insect larvae in tree-holes. The probability that a fake larva in a tree hole was attacked by predators ranged between 25-58% (95% CI) after two days and between 76-96% (95% CI) after two weeks. Overall, the highest attack rates were recorded for small mammals, followed by arthropods and birds. Arthropods took longer to detect potential prey items than small mammals and birds, and they were the only group that showed significant differences in attack rates between forest zones (unmanaged > managed). This study revealed that sentinel prey might be a suitable method for measuring the predation pressure from terrestrial predators on insect larvae in water-filled tree holes. |
The effects of oviposition site on the development of the wood borer Coraebus florentinus (Coleoptera: Buprestidae)Ana M. CÁRDENAS, Patricia GALLARDOEur. J. Entomol. 110 (1): 135-144, 2013 | DOI: 10.14411/eje.2013.019 Coraebus florentinus (Herbst) is one of the most important wood borer pests of oaks in forest ecosystems in the Mediterranean Region. It is considered to be a heliophilous species as it prefers the sunniest parts of the canopy of isolated trees. The biological significance of this preference is still unknown. Recently, the effect of temperature on the preimaginal development of this insect was established: high temperatures increase its probability of survival and shorten its developmental time. Continuing this line of research, this study was designed to determine whether C. florentinus exhibits selective oviposition behaviour and how variation in temperature due to differences in the position of the branches in which the larvae develop could affect the subsequent development of this species. To determine whether this insect selects the branches in which to lay its eggs, location data (north, south, upper half and lower half of the tops of the trees) for 112 damaged branches were analysed. The results confirm that females of C. florentinus do not lay their eggs at random at the tops of trees but rather choose branches that are exposed to the sun. To determine the effects of larval rearing temperature on the later development stages, an experiment consisting of five treatments was performed. Four of these treatments, each containing 25 infested branches derived from different orientations and positions in a tree (upper half of tree and north facing, upper half and south facing, lower half and north facing and lower half and south facing) were kept in culture chambers maintained at optimal conditions for pupal development (28 ± 2°C and 60-65% relative humidity). The fifth treatment with 25 branches infested collected from the most sun-exposed locations were kept in outdoor conditions. The results indicate that variation in temperature during larval development due to differences in branch location does not significantly affect survival, duration of developmental of pupae, emergence success or sex ratio of the adults. |



