ResearchPad - moths-and-butterflies https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Natural history museum collection and citizen science data show advancing phenology of Danish hoverflies (Insecta: Diptera, Syrphidae) with increasing annual temperature]]> https://www.researchpad.co/article/elastic_article_14485 We explore the phenological response by Danish hoverflies (Syrphidae) to continually rising annual temperatures by analysing >50.000 natural history collection and citizen science records for 37 species collected between 1900 and 2018, a period during which the annual average temperature in Denmark rose significantly (p << 0.01). We perform a simple linear regression analysis of the 10th percentile observation date for each species against year of observation. Fourteen of the species showed a statistically significant (p < 0.05) negative correlation between 10th percentile date and year of observation, indicating earlier emergence as a likely response to climatic warming. Eighteen species showed a non-significant (p ≥ 0.05) negative correlation between 10th percentile date and year of observation, while four species showed a non-significant (p ≥ 0.05) positive correlation, and one showed neither a positive nor a negative correlation. We explore the possible impact of the length of the data series on the regression analysis by dividing the species into four groups depending on how far back in time we have data: ultra-short series (with data from 2003–2018); short series (data from 1998–2018); medium series (data from 1980–2018); long series (data from 2018 to before 1980). The length of the series seems to have an effect on the results as 60% of the long series species (nine out of 15) showed a statistically significant negative correlation, while for the shorter series species less than 35% showed a statistically significant negative correlation. When we reduced the long series in length to short series, the proportion of statistically significant negative correlations fell to 33%, confirming this assumption. We conclude that northern temperate hoverflies generally react to the ongoing climatic warming by emerging earlier.

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<![CDATA[Global survey of mobile DNA horizontal transfer in arthropods reveals Lepidoptera as a prime hotspot]]> https://www.researchpad.co/article/5c5df307d5eed0c484580b72

More than any other genome components, Transposable Elements (TEs) have the capacity to move across species barriers through Horizontal Transfer (HT), with substantial evolutionary consequences. Previous large-scale surveys, based on full-genomes comparisons, have revealed the transposition mode as an important predictor of HT rates variation across TE superfamilies. However, host biology could represent another major explanatory factor, one that needs to be investigated through extensive taxonomic sampling. Here we test this hypothesis using a field collection of 460 arthropod species from Tahiti and surrounding islands. Through targeted massive parallel sequencing, we uncover patterns of HT in three widely-distributed TE superfamilies with contrasted modes of transposition. In line with earlier findings, the DNA transposons under study (TC1-Mariner) were found to transfer horizontally at the highest frequency, closely followed by the LTR superfamily (Copia), in contrast with the non-LTR superfamily (Jockey), that mostly diversifies through vertical inheritance and persists longer within genomes. Strikingly, across all superfamilies, we observe a marked excess of HTs in Lepidoptera, an insect order that also commonly hosts baculoviruses, known for their ability to transport host TEs. These results turn the spotlight on baculoviruses as major potential vectors of TEs in arthropods, and further emphasize the importance of non-vertical TE inheritance in genome evolution.

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<![CDATA[Moderate plant water stress improves larval development, and impacts immunity and gut microbiota of a specialist herbivore]]> https://www.researchpad.co/article/5c76fe62d5eed0c484e5b9b6

While host plant drought is generally viewed as a negative phenomenon, its impact on insect herbivores can vary largely depending on the species involved and on the intensity of the drought. Extreme drought killing host plants can clearly reduce herbivore fitness, but the impact of moderate host plant water stress on insect herbivores can vary, and may even be beneficial. The populations of the Finnish Glanville fritillary butterfly (Melitaea cinxia) have faced reduced precipitation in recent years, with impacts even on population dynamics. Whether the negative effects of low precipitation are solely due to extreme desiccation killing the host plant or whether moderate drought reduces plant quality for the larvae remains unknown. We assessed the performance of larvae fed on moderately water-stressed Plantago lanceolata in terms of growth, survival, and immune response, and additionally were interested to assess whether the gut microbial composition of the larvae changed due to modification of the host plant. We found that larvae fed on water-stressed plants had increased growth, with no impact on survival, up-regulated the expression of one candidate immune gene (pelle), and had a more heterogeneous bacterial community and a shifted fungal community in the gut. Most of the measured traits showed considerable variation due to family structure. Our data suggest that in temperate regions moderate host plant water stress can positively shape resource acquisition of this specialized insect herbivore, potentially by increasing nutrient accessibility or concentration. Potentially, the better larval performance may be mediated by a shift of the microbiota on water-stressed plants, calling for further research especially on the understudied gut fungal community.

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<![CDATA[Genetic dissection of assortative mating behavior]]> https://www.researchpad.co/article/5c65dcb4d5eed0c484dec08b

The evolution of new species is made easier when traits under divergent ecological selection are also mating cues. Such ecological mating cues are now considered more common than previously thought, but we still know little about the genetic changes underlying their evolution or more generally about the genetic basis for assortative mating behaviors. Both tight physical linkage and the existence of large-effect preference loci will strengthen genetic associations between behavioral and ecological barriers, promoting the evolution of assortative mating. The warning patterns of Heliconius melpomene and H. cydno are under disruptive selection due to increased predation of nonmimetic hybrids and are used during mate recognition. We carried out a genome-wide quantitative trait locus (QTL) analysis of preference behaviors between these species and showed that divergent male preference has a simple genetic basis. We identify three QTLs that together explain a large proportion (approximately 60%) of the difference in preference behavior observed between the parental species. One of these QTLs is just 1.2 (0–4.8) centiMorgans (cM) from the major color pattern gene optix, and, individually, all three have a large effect on the preference phenotype. Genomic divergence between H. cydno and H. melpomene is high but broadly heterogenous, and admixture is reduced at the preference–optix color pattern locus but not the other preference QTLs. The simple genetic architecture we reveal will facilitate the evolution and maintenance of new species despite ongoing gene flow by coupling behavioral and ecological aspects of reproductive isolation.

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<![CDATA[Leafflower–leafflower moth mutualism in the Neotropics: Successful transoceanic dispersal from the Old World to the New World by actively-pollinating leafflower moths]]> https://www.researchpad.co/article/5c5b529ed5eed0c4842bccc2

In the Old World tropics, several hundred species of leafflowers (Phyllanthus sensu lato; Phyllanthaceae) are engaged in obligate mutualisms with species-specific leafflower moths (Epicephala; Gracillariidae) whose adults actively pollinate flowers and larvae consume the resulting seeds. Considerable diversity of Phyllanthus also exists in the New World, but whether any New World Phyllanthus is pollinated by Epicephala is unknown. We studied the pollination biology of four woody Phyllanthus species occurring in Peru over a period of four years, and found that each species is associated with a species-specific, seed-eating Epicephala moth, here described as new species. Another Epicephala species found associated with herbaceous Phyllanthus is also described. This is the first description of Epicephala from the New World. Field-collected female moths of the four Epicephala species associated with woody Phyllanthus all carried pollen on the proboscises, and active pollination behavior was observed in at least two species. Thus, Epicephala moths also pollinate New World Phyllanthus. However, not all of these Epicephala species may be mutualistic with their hosts, because we occasionally observed females laying eggs in developing fruits without pollinating. Also, the flowers of some Phyllanthus species were visited by pollen-bearing thrips or gall midges, which potentially acted as co-pollinators or primary pollinators. Phylogenetic analysis showed that the New World Epicephala associated with woody Phyllanthus are nested within lineages of Old World active pollinators. Thus, actively-pollinating Epicephala moths, which originated in the Old World, successfully colonized the New World probably across the Pacific and established mutualisms with resident Phyllanthus species, although whether any of the relationships are obligate requires further study. There is likely a major radiation of Epicephala still to be found in the New World.

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<![CDATA[Artificial selection on storage protein 1 possibly contributes to increase of hatchability during silkworm domestication]]> https://www.researchpad.co/article/5c50c457d5eed0c4845e85bf

Like other domesticates, the efficient utilization of nitrogen resources is also important for the only fully domesticated insect, the silkworm. Deciphering the way in which artificial selection acts on the silkworm genome to improve the utilization of nitrogen resources and to advance human-favored domestication traits, will provide clues from a unique insect model for understanding the general rules of Darwin's evolutionary theory on domestication. Storage proteins (SPs), which belong to a hemocyanin superfamily, basically serve as a source of amino acids and nitrogen during metamorphosis and reproduction in insects. In this study, through blast searching on the silkworm genome and further screening of the artificial selection signature on silkworm SPs, we discovered a candidate domestication gene, i.e., the methionine-rich storage protein 1 (SP1), which is clearly divergent from other storage proteins and exhibits increased expression in the ova of domestic silkworms. Knockout of SP1 via the CRISPR/Cas9 technique resulted in a dramatic decrease in egg hatchability, without obvious impact on egg production, which was similar to the effect in the wild silkworm compared with the domestic type. Larval development and metamorphosis were not affected by SP1 knockout. Comprehensive ova comparative transcriptomes indicated significant higher expression of genes encoding vitellogenin, chorions, and structural components in the extracellular matrix (ECM)-interaction pathway, enzymes in folate biosynthesis, and notably hormone synthesis in the domestic silkworm, compared to both the SP1 mutant and the wild silkworm. Moreover, compared with the wild silkworms, the domestic one also showed generally up-regulated expression of genes enriched in the structural constituent of ribosome and amide, as well as peptide biosynthesis. This study exemplified a novel case in which artificial selection could act directly on nitrogen resource proteins, further affecting egg nutrients and eggshell formation possibly through a hormone signaling mediated regulatory network and the activation of ribosomes, resulting in improved biosynthesis and increased hatchability during domestication. These findings shed new light on both the understanding of artificial selection and silkworm breeding from the perspective of nitrogen and amino acid resources.

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<![CDATA[A quadratic trigonometric spline for curve modeling]]> https://www.researchpad.co/article/5c40f762d5eed0c48438600c

An imperative curve modeling technique has been established with a view to its applications in various disciplines of science, engineering and design. It is a new spline method using piecewise quadratic trigonometric functions. It possesses error bounds of order 3. The proposed curve model also owns the most favorable geometric properties. The proposed spline method accomplishes C2 smoothness and produces a Quadratic Trigonometric Spline (QTS) with the view to its applications in curve design and control. It produces a C2 quadratic trigonometric alternative to the traditional cubic polynomial spline (CPS) because of having four control points in its piecewise description. The comparison analysis of QTS and CPS verifies the QTS as better alternate to CPS. Also, the time analysis proves QTS computationally efficient than CPS.

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<![CDATA[Mark-release-recapture meets Species Distribution Models: Identifying micro-habitats of grassland butterflies in agricultural landscapes]]> https://www.researchpad.co/article/5c0841abd5eed0c484fca667

Habitat demands and species mobility strongly determine the occurrence of species. Sedentary species with specific habitat requirements are assumed to occur more patchy than mobile habitat generalist species, and thus suffer stronger under habitat fragmentation and habitat deterioration. In this study we measured dispersal and habitat preference of three selected butterfly species using mark-release-recapture technique. We used data on species abundance to calculate Species Distribution Models based on high-resolution aerial photographs taken using RGB / NIR cameras mounted on a UAV. We found that microhabitats for species with specific habitat requirements occur spatially restricted. In contrast, suitable habitats are more interconnected and widespread for mobile habitat generalists. Our models indicate that even managed grassland sites have comparatively little habitat quality, while road verges provide high quality micro-habitats. In addition, dispersal was more restricted for specialist butterfly species, and higher for the two other butterfly species with less ecological specialisation. This study shows synergies arising when combining ecological data with high precision aerial pictures and Species Distribution Models, to identify micro-habitats for butterflies. This approach might be suitable to identify and conserve high quality habitats, and to improve nature conservation at the ground.

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<![CDATA[Interactive effects of precipitation and nitrogen enrichment on multi-trophic dynamics in plant-arthropod communities]]> https://www.researchpad.co/article/5b6da1b0463d7e4dccc5faeb

Patterns of precipitation and nitrogen (N) deposition are changing in ecosystems worldwide. Simultaneous increases in precipitation and N deposition can relieve co-limiting soil resource conditions for plants and result in synergistic plant responses, which may affect animals and plant responses to higher trophic levels. However, the potential for synergistic effects of precipitation and N deposition on animals and plant responses to herbivores and predators (via trophic cascades) is unclear. We investigated the influence of precipitation and N enrichment on ecological dynamics across three trophic levels, hypothesizing that herbivores and plants would exhibit synergistic responses to the combined influence of precipitation, N amendments and predators. To test this, we conducted a field experiment with arthropods on two model plant species, Nicotiana tabacum and Nicotiana rustica. First, we characterized the plant-arthropod assemblages, finding that N. tabacum hosted greater abundances of caterpillars, while N. rustica hosted more sap-sucking herbivores. Next, we evaluated the effects of rainwater, soil N, and predatory spider manipulations for both plant-arthropod assemblages. On N. tabacum, water and N availability had an interactive effect on caterpillars, where caterpillars were most abundant with rainwater additions and least abundant when both rainwater and N were added. For N. rustica, foliar chemistry had a synergistic response to all three experimental factors. Compared to spider-absent conditions, leaf N concentration increased and C/N decreased when spiders were present, but this response only occurred under high water and N availability. Spiders indirectly altered plant chemistry via a facilitative effect of spiders on sap-sucking herbivores, potentially due to intra-guild predation, and a positive effect of sap-suckers on foliar N concentration. Our study suggests that predictions of the ecological impacts of altered precipitation and N deposition may need to account for the effects of resource co-limitation on dynamics across trophic levels.

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<![CDATA[<i>PLoS Computational Biology</i> Issue Image | Vol. 14(11) November 2018]]> https://www.researchpad.co/article/5c0ae482d5eed0c484589d9c

Moth antennal neurons adjust their encoding optimally with respect to pheromone fluctuations

Sensory neural systems of living organisms encode the representation of their environment with remarkable efficiency. This is manifested, e.g., in the way how male moths perform long-distance searches of their females by tracking the pheromone plumes. In the study "Moth olfactory receptor neurons adjust their encoding efficiency to temporal statistics of pheromone fluctuations" Levakova et al. analyzed responses of pheromone-specific antennal neurons to naturalistic stimulation. It was shown that the coding accuracy and the stimulus distribution are in the optimal relationship as predicted by both information theory and statistical estimation theory.

Image Credit: Marie Levakova

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<![CDATA[Changes in Species Richness and Composition of Tiger Moths (Lepidoptera: Erebidae: Arctiinae) among Three Neotropical Ecoregions]]> https://www.researchpad.co/article/5989daf3ab0ee8fa60bc206a

Paraná, Yungas and Chaco Serrano ecoregions are among the most species-rich terrestrial habitats at higher latitude. However, the information for tiger moths, one of the most speciose groups of moths, is unknown in these ecoregions. In this study, we assess their species richness and composition in all three of these ecoregions. Also we investigated whether the species composition of tiger moths is influenced by climatic factors and altitude. Tiger moth species were obtained with samples from 71 sites using standardized protocols (21 sites were in Yungas, 19 in Paraná and 31 in Chaco Serrano). Rarefaction-extrapolation curves, non-parametric estimators for incidence and sample coverage indices were performed to assess species richness in the ecoregions studied. Non metric multidimensional scaling and adonis tests were performed to compare the species composition of tiger moths among ecoregions. Permutest analysis and Pearson correlation were used to evaluate the relationship among species composition and annual mean temperature, annual temperature range, annual precipitation, precipitation seasonality and altitude. Among ecoregions Paraná was the richest with 125 species, followed by Yungas with 63 species and Chaco Serrano with 24 species. Species composition differed among these ecoregions, although Yungas and Chaco Serrano were more similar than Paraná. Species composition was significantly influenced by climatic factors and altitude. This study showed that species richness and species composition of tiger moths differed among the three ecoregions assessed. Furthermore, not only climatic factors and altitude influence the species composition of tiger moths among ecoregions, but also climatic seasonality at higher latitude in Neotropical South America becomes an important factor.

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<![CDATA[Is the Combination of Insecticide and Mating Disruption Synergistic or Additive in Lightbrown Apple Moth, Epiphyas postvittana?]]> https://www.researchpad.co/article/5989da37ab0ee8fa60b86c16

Pest suppression from combinations of tactics is fundamental to pest management and eradication. Interactions may occur among tactical combinations and affect suppression. The best case is synergistic, where suppression from a combination is greater than the sum of effects from single tactics (AB >> A+B). We explored how mating disruption and insecticide interacted at field scale, additively or synergistically. Use of a pheromone delivery formulation (SPLAT) as either a mating disruption treatment (i.e. a two-component pheromone alone) or as a lure and kill treatment (i.e. the two-component pheromone plus a permethrin insecticide) was compared for efficacy against the lightbrown apple moth Epiphyas postvittana. Next, four point-source densities of the SPLAT formulations were compared for communication disruption. Finally, the mating disruption and lure and kill treatments were applied with a broadcast insecticide. Population assessment used virgin female traps and synthetic pheromone in replicated 9-ha vineyard plots compared with untreated controls and insecticide-treated plots, to investigate interactions. Lure and kill and mating disruption provided equivalent suppression; no additional benefit accrued from including permethrin with the pheromone suggesting lack of contact. The highest point-source density tested (625/ha) was most effective. The insect growth regulator methoxyfenoxide applied by broadcast application lowered pest prevalence by 70% for the first ten weeks compared to pre-trial. Pheromone addition suppressed the pest further by an estimated 92.5%, for overall suppression of 97.7% from the treatment combination of insecticide plus mating disruption. This was close to that expected for an additive model of interactivity between insecticide and mating disruption (AB = A+B) estimated from plots with single tactics as 98% suppression in a combination. The results indicate the need to examine other tactical combinations to achieve the potential cost-efficiencies of synergistic interactions.

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<![CDATA[Population Explosions of Tiger Moth Lead to Lepidopterism Mimicking Infectious Fever Outbreaks]]> https://www.researchpad.co/article/5989da4fab0ee8fa60b8d9d0

Lepidopterism is a disease caused by the urticating scales and toxic fluids of adult moths, butterflies or its caterpillars. The resulting cutaneous eruptions and systemic problems progress to clinical complications sometimes leading to death. High incidence of fever epidemics were associated with massive outbreaks of tiger moth Asota caricae adult populations during monsoon in Kerala, India. A significant number of monsoon related fever characteristic to lepidopterism was erroneously treated as infectious fevers due to lookalike symptoms. To diagnose tiger moth lepidopterism, we conducted immunoblots for tiger moth specific IgE in fever patients’ sera. We selected a cohort of patients (n = 155) with hallmark symptoms of infectious fevers but were tested negative to infectious fevers. In these cases, the total IgE was elevated and was detected positive (78.6%) for tiger moth specific IgE allergens. Chemical characterization of caterpillar and adult moth fluids was performed by HPLC and GC-MS analysis and structural identification of moth scales was performed by SEM analysis. The body fluids and chitinous scales were found to be highly toxic and inflammatory in nature. To replicate the disease in experimental model, wistar rats were exposed to live tiger moths in a dose dependant manner and observed similar clinico-pathological complications reported during the fever epidemics. Further, to link larval abundance and fever epidemics we conducted cointegration test for the period 2009 to 2012 and physical presence of the tiger moths were found to be cointegrated with fever epidemics. In conclusion, our experiments demonstrate that inhalation of aerosols containing tiger moth fluids, scales and hairs cause systemic reactions that can be fatal to human. All these evidences points to the possible involvement of tiger moth disease as a major cause to the massive and fatal fever epidemics observed in Kerala.

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<![CDATA[Past Human Disturbance Effects upon Biodiversity are Greatest in the Canopy; A Case Study on Rainforest Butterflies]]> https://www.researchpad.co/article/5989db25ab0ee8fa60bd011f

A key part of tropical forest spatial complexity is the vertical stratification of biodiversity, with widely differing communities found in higher rainforest strata compared to terrestrial levels. Despite this, our understanding of how human disturbance may differentially affect biodiversity across vertical strata of tropical forests has been slow to develop. For the first time, how the patterns of current biodiversity vary between three vertical strata within a single forest, subject to three different types of historic anthropogenic disturbance, was directly assessed. In total, 229 species of butterfly were detected, with a total of 5219 individual records. Butterfly species richness, species diversity, abundance and community evenness differed markedly between vertical strata. We show for the first time, for any group of rainforest biodiversity, that different vertical strata within the same rainforest, responded differently in areas with different historic human disturbance. Differences were most notable within the canopy. Regenerating forest following complete clearance had 47% lower canopy species richness than regenerating forest that was once selectively logged, while the reduction in the mid-storey was 33% and at ground level, 30%. These results also show for the first time that even long term regeneration (over the course of 30 years) may be insufficient to erase differences in biodiversity linked to different types of human disturbance. We argue, along with other studies, that ignoring the potential for more pronounced effects of disturbance on canopy fauna, could lead to the underestimation of the effects of habitat disturbance on biodiversity, and thus the overestimation of the conservation value of regenerating forests more generally.

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<![CDATA[Fast Census of Moth Diversity in the Neotropics: A Comparison of Field-Assigned Morphospecies and DNA Barcoding in Tiger Moths]]> https://www.researchpad.co/article/5989da94ab0ee8fa60ba12a6

The morphological species delimitations (i.e. morphospecies) have long been the best way to avoid the taxonomic impediment and compare insect taxa biodiversity in highly diverse tropical and subtropical regions. The development of DNA barcoding, however, has shown great potential to replace (or at least complement) the morphospecies approach, with the advantage of relying on automated methods implemented in computer programs or even online rather than in often subjective morphological features. We sampled moths extensively for two years using light traps in a patch of the highly endangered Atlantic Forest of Brazil to produce a nearly complete census of arctiines (Noctuoidea: Erebidae), whose species richness was compared using different morphological and molecular approaches (DNA barcoding). A total of 1,075 barcode sequences of 286 morphospecies were analyzed. Based on the clustering method Barcode Index Number (BIN) we found a taxonomic bias of approximately 30% in our initial morphological assessment. However, a morphological reassessment revealed that the correspondence between morphospecies and molecular operational taxonomic units (MOTUs) can be up to 94% if differences in genitalia morphology are evaluated in individuals of different MOTUs originated from the same morphospecies (putative cases of cryptic species), and by recording if individuals of different genders in different morphospecies merge together in the same MOTU (putative cases of sexual dimorphism). The results of two other clustering methods (i.e. Automatic Barcode Gap Discovery and 2% threshold) were very similar to those of the BIN approach. Using empirical data we have shown that DNA barcoding performed substantially better than the morphospecies approach, based on superficial morphology, to delimit species of a highly diverse moth taxon, and thus should be used in species inventories.

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<![CDATA[LBD1 of Vitellogenin Receptor Specifically Binds to the Female-Specific Storage Protein SP1 via LBR1 and LBR3]]> https://www.researchpad.co/article/5989d9e7ab0ee8fa60b6ba3d

Storage proteins are the major protein synthesized in the fat body, released into hemolymph and re-sequestered into the fat body before pupation in most insect species. Storage proteins are important amino acid and nutrition resources during the non-feeding pupal period and play essential roles for the metamorphosis and oogenesis of insects. The sequestration of storage protein is a selective, specific receptor-mediated process. However, to date, the potential receptor mediating the sequestration of storage protein has not been determined in Bombyx mori. In this study, we expressed and purified the first ligand binding domain of Bombyx mori vitellogenin receptor (BmVgR), LBD1, and found LBD1 could bind with an unknown protein from the hemolymph of the ultimate silkworm larval instar via pull-down assay. This unknown protein was subsequently identified to be the female-specific storage protein SP1 by mass spectrometry. Furthermore, far western blotting assay, immunoprecipitation and isothermal titration calorimetry analysis demonstrated LBD1 specifically bound with the female-specific SP1, rather than another unisex storage protein SP2. The specific binding of LBD1 with SP1 was dependent on the presence of Ca2+ as it was essential for the proper conformation of LBD1. Deletion mutagenesis and ITC analysis revealed the first and third ligand binding repeats LBR1 and LBR3 were indispensable for the binding of LBD1 with SP1, and LBR2 and LBR4 also had a certain contribution to the specific binding. Our results implied BmVgR may mediate the sequestration of SP1 from hemolymph into the fat body during the larval-pupal transformation of Bombyx mori.

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<![CDATA[Molecular Characterization of a Lysozyme Gene and Its Altered Expression Profile in Crowded Beet Webworm (Loxostege sticticalis)]]> https://www.researchpad.co/article/5989dae3ab0ee8fa60bbc642

There is growing evidence that insects living in high-density populations exhibit an increase in immune function to counter a higher risk of disease. This phenomenon, known as density-dependent prophylaxis, has been experimentally tested in a number of insect species. Although density-dependent prophylaxis is especially prevalent in insects exhibiting density-dependent phase polyphenism, the molecular mechanism remains unclear. Our previous study demonstrated that the antibacterial activity of lysozyme is important for this process in the beet webworm Loxostege sticticalis. In this study, a lysozyme cDNA from L. sticticalis was cloned and characterized. The full-length cDNA is 1078 bp long and contains an open reading frame of 426 bp that encodes 142 amino acids. The deduced protein possesses structural characteristics of a typical c-type lysozyme and clusters with c-type lysozymes from other Lepidoptera. LsLysozyme was found to be expressed throughout all developmental stages, showing the highest level in pupae. LsLysozyme was also highly expressed in the midgut and fat body. Elevated LsLysozyme expression was observed in L. sticticalis larvae infected by Beauveria bassiana and in larvae reared under crowding conditions. In addition, the expression level of LsLysozyme in infected larvae reared at a density of 10 larvae per jar was significantly higher compared to those reared at a density of l or 30 larvae per jar. These results suggest that larval crowding affects the gene expression profile of this lysozyme. This study provides additional insight into the expression of an immune-associated lysozyme gene and helps us to better understand the immune response of L. sticticalis under crowding conditions.

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<![CDATA[Development of a Genomic Resource and Quantitative Trait Loci Mapping of Male Calling Traits in the Lesser Wax Moth, Achroia grisella]]> https://www.researchpad.co/article/5989da5fab0ee8fa60b90b49

In the study of sexual selection among insects, the Lesser Waxmoth, Achroia grisella (Lepidoptera: Pyralidae), has been one of the more intensively studied species over the past 20 years. Studies have focused on how the male calling song functions in pair formation and on the quantitative genetics of male song characters and female preference for the song. Recent QTL studies have attempted to elucidate the genetic architecture of male song and female preference traits using AFLP markers. We continued these QTL studies using SNP markers derived from an EST library that allowed us to measure both DNA sequence variation and map loci with respect to the lepidopteran genome. We report that the level of sequence variation within A. grisella is typical among other Lepidoptera that have been examined, and that comparison with the Bombyx mori genome shows that macrosynteny is conserved. Our QTL map shows that a QTL for a male song trait, pulse-pair rate, is situated on the Z chromosome, a prediction for sexually selected traits in Lepidoptera. Our findings will be useful for future studies of genetic architecture of this model species and may help identify the genetics associated with the evolution of its novel acoustic communication.

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<![CDATA[Ellenberg's indicator values support prediction of suitable habitat for pre-diapause larvae of endangered butterfly Euphydryas aurinia]]> https://www.researchpad.co/article/5989db5dab0ee8fa60be0479

In spite of the great popularity of Ellenberg’s Indicator Values (EIVs) in plant ecology, animal ecologists seldom use EIVs to address ecological questions. In this study we used EIVs to test their potential usefulness for the prediction of suitable habitat for pre-diapause larvae of the endangered butterfly species Euphydryas aurinia. Nine transects crossing grasslands in SW Poland with abundant populations of E. aurinia were designed. We sampled 76 vegetation plots along the transects. In addition, the presence of the larval webs of E. aurinia in sampled plots was also recorded. We then calculated the mean community EIVs of light, nitrogen, soil reaction, moisture and temperature for each sample plots. Generalized linear mixed-effects models (GLMMs) were used to assess which factors determine the local occurrence of larval webs of E. aurinia. We found the larval webs only in 12 plots, while the host plant was present in 39 of the examined plots. The presence of the host plant was the most important predictor in both models including all plots or including only plots with host plants. The other significant predictor was the mean EIV of light, and its importance increased in models considering all plots. We attributed the importance of the EIV of light to the site openness and density of the vegetation layer. A positive relationship between this predictor and the presence of larval webs indicates that sites with looser vegetation, a lower contribution of shrubs and tall herbs and better penetration of photosynthetically active radiation to lower vegetation layers are preferred by E. aurinia for oviposition. Moreover, the significance of EIV of light may be linked with management practices. Many light-demanding species decline after cessation of mowing as a result of litter accumulation and the dominance of tall herbs. An absence of light-demanding species decreases the community’s mean EIV of light and thus indicates the influence of meadow abandonment.

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<![CDATA[Hygienic and grooming behaviors in African and European honeybees—New damage categories in Varroa destructor]]> https://www.researchpad.co/article/5989db5fab0ee8fa60be1105

Varroa destructor is an ectoparasitic pest of honeybees, and a threat to the survival of the apiculture industry. Several studies have shown that unlike European honeybees, African honeybee populations appear to be minimally affected when attacked by this mite. However, little is known about the underlying drivers contributing to survival of African honeybee populations against the mite. We hypothesized that resistant behavioral defenses are responsible for the survival of African honeybees against the ectoparasite. We tested this hypothesis by comparing grooming and hygienic behaviors in the African savannah honeybee Apis mellifera scutellata in Kenya and A. mellifera hybrids of European origin in Florida, USA against the mite. Grooming behavior was assessed by determining adult mite infestation levels, daily mite fall per colony and percentage mite damage (as an indicator of adult grooming rate), while hygienic behavior was assessed by determining the brood removal rate after freeze killing a section of the brood. Our results identified two additional undescribed damaged mite categories along with the six previously known damage categories associated with the grooming behavior of both honeybee subspecies. Adult mite infestation level was approximately three-fold higher in A. mellifera hybrids of European origin than in A. m. scutellata, however, brood removal rate, adult grooming rate and daily natural mite fall were similar in both honeybee subspecies. Unlike A. mellifera hybrids of European origin, adult grooming rate and brood removal rate did not correlate with mite infestation levels on adult worker honeybee of A. m. scutellata though they were more aggressive towards the mites than their European counterparts. Our results provide valuable insights into the tolerance mechanisms that contribute to the survival of A. m. scutellata against the mite.

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