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1.
Proc Natl Acad Sci U S A ; 117(13): 7271-7275, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32152101

RESUMO

Evidence for global insect declines mounts, increasing our need to understand underlying mechanisms. We test the nutrient dilution (ND) hypothesis-the decreasing concentration of essential dietary minerals with increasing plant productivity-that particularly targets insect herbivores. Nutrient dilution can result from increased plant biomass due to climate or CO2 enrichment. Additionally, when considering long-term trends driven by climate, one must account for large-scale oscillations including El Niño Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), and Pacific Decadal Oscillation (PDO). We combine long-term datasets of grasshopper abundance, climate, plant biomass, and end-of-season foliar elemental content to examine potential drivers of abundance cycles and trends of this dominant herbivore. Annual grasshopper abundances in 16- and 22-y time series from a Kansas prairie revealed both 5-y cycles and declines of 2.1-2.7%/y. Climate cycle indices of spring ENSO, summer NAO, and winter or spring PDO accounted for 40-54% of the variation in grasshopper abundance, mediated by effects of weather and host plants. Consistent with ND, grass biomass doubled and foliar concentrations of N, P, K, and Na-nutrients which limit grasshopper abundance-declined over the same period. The decline in plant nutrients accounted for 25% of the variation in grasshopper abundance over two decades. Thus a warming, wetter, more CO2-enriched world will likely contribute to declines in insect herbivores by depleting nutrients from their already nutrient-poor diet. Unlike other potential drivers of insect declines-habitat loss, light and chemical pollution-ND may be widespread in remaining natural areas.


Assuntos
Conservação dos Recursos Naturais/tendências , Demografia/tendências , Gafanhotos , Animais , Biomassa , Mudança Climática/estatística & dados numéricos , Ecossistema , El Niño Oscilação Sul , Pradaria , Herbivoria , Insetos , Kansas , Nutrientes , Poaceae , Estações do Ano , Tempo (Meteorologia)
2.
J Chem Ecol ; 48(2): 121-140, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35001201

RESUMO

Chemoreception plays a crucial role in the reproduction and survival of insects, which often rely on their sense of smell and taste to find partners, suitable habitats, and food sources, and to avoid predators and noxious substances. There is a substantial body of work investigating the chemoreception and chemical ecology of Diptera (flies) and Lepidoptera (moths and butterflies); but less is known about the Orthoptera (grasshoppers, locusts, crickets, and weta). Within the Orthoptera, the family Acrididae contains about 6700 species of short-horned grasshoppers. Grasshoppers are fascinating organisms to study due to their significant taxonomic and ecological divergence, however, most chemoreception and chemical ecology studies have focused on locusts because they are agricultural pests (e.g., Schistocerca gregaria and Locusta migratoria). Here we review studies of chemosensory systems and chemical ecology of all short-horned grasshoppers. Applications of genome editing tools and entomopathogenic microorganism to control locusts in association with their chemical ecology are also discussed. Finally, we identify gaps in the current knowledge and suggest topics of interest for future studies.


Assuntos
Borboletas , Gafanhotos , Animais , Ecossistema , Olfato
3.
Int J Mol Sci ; 23(2)2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35055035

RESUMO

Bacteria of the Wolbachia genus are maternally inherited symbionts of Nematoda and numerous Arthropoda hosts. There are approximately 20 lineages of Wolbachia, which are called supergroups, and they are designated alphabetically. Wolbachia strains of the supergroups A and B are predominant in arthropods, especially in insects, and supergroup F seems to rank third. Host taxa have been studied very unevenly for Wolbachia symbionts, and here, we turn to one of largely unexplored insect families: Acrididae. On the basis of five genes subject to multilocus sequence typing, we investigated the incidence and genetic diversity of Wolbachia in 41 species belonging three subfamilies (Gomphocerinae, Oedipodinae, and Podisminae) collected in Turkey, Kazakhstan, Tajikistan, Russia, and Japan, making 501 specimens in total. Our results revealed a high incidence and very narrow genetic diversity of Wolbachia. Although only the strains belonging to supergroups A and B are commonly present in present, the Acrididae hosts here proved to be infected with supergroups B and F without A-supergroup variants. The only trace of an A-supergroup lineage was noted in one case of an inter-supergroup recombinant haplotype, where the ftsZ gene came from supergroup A, and the others from supergroup B. Variation in the Wolbachia haplotypes in Acrididae hosts within supergroups B and F was extremely low. A comprehensive genetic analysis of Wolbachia diversity confirmed specific features of the Wolbachia allelic set in Acrididae hosts. This result can help to elucidate the crucial issue of Wolbachia biology: the route(s) and mechanism(s) of Wolbachia horizontal transmission.


Assuntos
Variação Genética , Gafanhotos/microbiologia , Wolbachia/classificação , Wolbachia/genética , Animais , Transferência Genética Horizontal , Insetos/microbiologia , Tipagem de Sequências Multilocus , Filogenia , Simbiose
4.
Genomics ; 112(1): 289-296, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30790624

RESUMO

Oxya is a genus of grasshoppers (Orthoptera: Acridoidea) attacking rice and other gramineous plants in Africa and Asia. In the present study, we characterized complete mitochondrial genomes (mitogenomes) of three species, Oxya japonica japonica (15,427 bp), Oxya hainanensis (15,443 bp) and Oxya agavisa robusta (15,552 bp) collected from China. The three mitogenomes contained a typical gene set of metazoan mitogenomes and shared the same gene order with other Acridid grasshoppers, including the rearrangement of tRNAAsp and tRNALys. Analyses of pairwise genetic distances showed that ATP8 was the least conserved gene, while COI the most conserved. To determine the position of Oxya grasshoppers in the phylogeny of Acrididae, we reconstructed phylogenetic trees among 64 species from across 11 subfamilies using nucleotide sequences of mitogenomes. While the tree confirms traditional classifications of Acrididae at major higher-levels, it suggests a few modifications for classifications at lower-levels.


Assuntos
Genoma Mitocondrial , Gafanhotos/genética , Animais , Composição de Bases , DNA Mitocondrial/química , Genes de RNAr , Gafanhotos/classificação , Proteínas Mitocondriais/genética , Filogenia , RNA de Transferência/genética
5.
Syst Parasitol ; 98(4): 487-501, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34215970

RESUMO

Mites (Acari) represent important parasites for a diverse range of hosts. Within the Acari, the Prostigmata represent a diverse suborder of the order Trombidiformes with about 20 000 species, including parasitic forms on both vertebrates and invertebrates. Within the Prostigmata, the genus Locustacarus (Heterostigmata: Podapolipidae) is particularly known as an intratracheal parasite of bumblebees and grasshoppers. In a survey on prostigmatic mites (Acari: Trombidiformes: Prostigmata) associated with insects in the eastern parts of Iran, one new species of the endoparasitic Locustacarus was collected associated to the grasshopper Aiolopus thalassinus (Fabricius) (Orthoptera: Acrididae). This new species, Locustacarus aiolopi Rahmatzaei & Hajiqanbar n. sp., is described here and compared morphologically with other species of the genus. This new species represents the first record of a grasshopper-associated Locustacarus species in the Palearctic. We further provide a comprehensive review of the global distribution of this genus as well as its host range.


Assuntos
Gafanhotos/parasitologia , Especificidade de Hospedeiro , Ácaros/classificação , Animais , Irã (Geográfico) , Ácaros/anatomia & histologia , Especificidade da Espécie
6.
BMC Evol Biol ; 20(1): 63, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32487064

RESUMO

BACKGROUND: Local coexistence of distinct, genetically determined color morphs can be unstable and transitional. Stable, long-term coexistence requires some form of balancing selection to protect morphs from getting lost by directional selection or genetic drift. However, not all phenotypic polymorphism need to have a genetic basis. We here report on the genetic basis of two color polymorphisms in the club-legged grasshopper Gomphocerus sibiricus: a green-brown polymorphism that is phylogenetically and geographically widespread among orthopteran insects and a pied-brown pattern polymorphism that is shared among many gomphocerine grasshoppers. RESULTS: We found a remarkably clear outcome of matings within and between morph that suggest not only that the green-brown polymorphism is heritable in this species, but that results can be most parsimoniously explained by a single autosomal locus with two alleles in which the green allele is dominant over the brown allele. A few individuals did not match this pattern and suggest the existence of genetic modifiers and/or developmental phenocopies. We also show that the pied-brown polymorphism is highly heritable, although the evidence for the involvement of one or more loci is less clear-cut. CONCLUSIONS: Overall, our data demonstrate that the two polymorphisms are heritable in the club-legged grasshopper and appear genetically simple, at least with respect to green morphs. The results are consistent with the idea that the synthesis or transport of a pigment involved in the production of green coloration (likely biliverdin) is lost by homozygosity for loss-of-function alleles in brown individuals. The apparently simple genetic architecture of the green-brown polymorphism offer potential for studying balancing selection in the field and for genetic mapping in this species.


Assuntos
Gafanhotos/genética , Pigmentação/genética , Polimorfismo Genético , Alelos , Animais , Fenótipo
7.
J Invertebr Pathol ; 177: 107504, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33217422

RESUMO

En masse inoculations with Paranosema locustae, an intracellular parasite of adipose tissue of grasshoppers and locusts and the only microsporidium registered as a biocontrol agent, were conducted against crowded fourth-instar nymphs of the South American locust Schistocerca cancellata and the grasshoppers Dichroplus schulzi and Ronderosia bergii. Infection did not develop in the locust, but was highly prevalent in the two grasshopper species. We hypothesize that absolute absence of infection in S. cancellata may constitute a case of density-dependent prophylactic resistance, an elevation of the baseline immunity of an organism in order to cope with disease that is prevalent in species exhibiting phase polyphenism.


Assuntos
Agentes de Controle Biológico/farmacologia , Gafanhotos/microbiologia , Microsporídios/fisiologia , Controle Biológico de Vetores , Animais , Gafanhotos/crescimento & desenvolvimento , Controle de Insetos , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologia
8.
BMC Genomics ; 20(1): 370, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088494

RESUMO

BACKGROUND: The club-legged grasshopper Gomphocerus sibiricus is a Gomphocerinae grasshopper with a promising future as model species for studying the maintenance of colour-polymorphism, the genetics of sexual ornamentation and genome size evolution. However, limited molecular resources are available for this species. Here, we present a de novo transcriptome assembly as reference resource for gene expression studies. We used high-throughput Illumina sequencing to generate 5,070,036 paired-end reads after quality filtering. We then combined the best-assembled contigs from three different de novo transcriptome assemblers (Trinity, SOAPdenovo-trans and Oases/Velvet) into a single assembly. RESULTS: This resulted in 82,251 contigs with a N50 of 1357 and a TransRate assembly score of 0.325, which compares favourably with other orthopteran transcriptome assemblies. Around 87% of the transcripts could be annotated using InterProScan 5, BLASTx and the dammit! annotation pipeline. We identified a number of genes involved in pigmentation and green pigment metabolism pathways. Furthermore, we identified 76,221 putative single nucleotide polymorphisms residing in 8400 contigs. We also assembled the mitochondrial genome and investigated levels of sequence divergence with other species from the genus Gomphocerus. Finally, we detected and assembled Wolbachia sequences, which revealed close sequence similarity to the strain pel wPip. CONCLUSIONS: Our study has generated a significant resource for uncovering genotype-phenotype associations in a species with an extraordinarily large genome, while also providing mitochondrial and Wolbachia sequences that will be useful for comparative studies.


Assuntos
Perfilação da Expressão Gênica/métodos , Gafanhotos/genética , Mitocôndrias/genética , Análise de Sequência de RNA/métodos , Animais , Mapeamento de Sequências Contíguas , Feminino , Estudos de Associação Genética , Tamanho do Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Anotação de Sequência Molecular
9.
J Evol Biol ; 32(4): 331-342, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30693584

RESUMO

A fundamental part of the quantitative genetic theory deals with the partitioning of the phenotypic variance into additive genetic and environmental components. During interaction with conspecifics, the interaction partner becomes a part of the environment from the perspective of the focal individual. If the interaction effects have a genetic basis, they are called indirect genetic effects (IGEs) and can evolve along with direct genetic effects. Sexual reproduction is a classic context where potential conflict between males and females can arise from trade-offs between current and future investments. We studied five female fecundity traits, egg length and number, egg pod length and number and latency to first egg pod, and estimated the direct and IGEs using a half-sib breeding design in the grasshopper Chorthippus biguttulus. We found that the male IGEs were an order of magnitude lower than the direct genetic effects and were not significantly different from zero. However, there was some indication that IGEs were larger shortly after mating, consistent with the idea that IGEs fade with time after interaction. Female direct heritabilities were moderate to low. Simulation shows that the variance component estimates can appear larger with less data, calling for care when interpreting variance components estimated with low power. Our results illustrate that the contribution of male IGEs is overall low on the phenotypic variance of female fecundity traits. Thus, even in the relevant context of sexual conflict, the influence of male IGEs on the evolutionary trajectory of female reproductive traits is likely to be small.


Assuntos
Gafanhotos/genética , Animais , Feminino , Masculino , Preferência de Acasalamento Animal , Óvulo/citologia , Reprodução/genética
10.
Ecol Lett ; 21(10): 1467-1476, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30039540

RESUMO

The canonical factors typically thought to determine herbivore community structure often explain only a small fraction of the variation in herbivore abundance and diversity. We tested how macronutrients and relatively understudied micronutrients interacted to influence the structure of insect herbivore (orthopteran) communities. We conducted a factorial fertilisation experiment manipulating macronutrients (N and P, added together) and micronutrients (Ca, Na and K) in large plots (30 × 30 m2 ) in a Texas coastal prairie. Although no single or combination of micronutrients affected herbivore communities in the absence of additional macronutrients, macronutrients and sodium added together increased herbivore abundance by 60%, richness by 15% and diversity by 20%. These results represent the first large-scale manipulation of single micronutrients and macronutrients in concert, and revealed an herbivore community co-limited by macronutrients and Na. Our work supports an emerging paradigm that Na may be important in limiting herbivore communities.


Assuntos
Herbivoria , Insetos , Sódio , Animais , Ecossistema , Pradaria , Nutrientes , Texas
11.
J Chem Ecol ; 42(12): 1304-1313, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27873056

RESUMO

Living in high-density groups of animals has advantages and disadvantages for mating. The advantage of facilitated mate finding is compromised by difficulties in protecting a suitable partner from competitors. Thus, males regularly are faced with increased competition for sperm, and females with harassment by males at high population densities. To cope with these problems, mating tactics and mate choice mechanisms have to be adjusted. An adaptation to gregarious condition observed in locusts includes the use of male-emitted pheromones. Males of the Central American locust, Schistocerca piceifrons, release sex-specific volatiles, which were identified as phenethyl alcohol (synonym: phenyl-ethyl-alcohol, 2-phenyl-1-ethanol, 2-phenylethanol, PEA), (Z)-3-nonen-1-ol (3-Nol), and (Z)-2-octen-1-ol (2-Ool). The emission of the two major compounds, PEA and 3-Nol, was restricted to crowded conditions. Furthermore, the release of both volatiles was coupled to males reaching sexual maturity, indicating a function in reproductive behavior. However, neither the single substances nor their mixtures were attractive or repellent to the locusts. Instead, females prefer the sperm of high pheromone-emitting males to fertilize their ova. In this way, the male-specific volatiles act as mate assessment pheromones utilized in a context of cryptic female choice. This function is well supported by the highly variable but individual-specific emission rates of the three compounds. Schistocerca piceifrons males release a virtually unique personal pheromone signature, a prerequisite for mate assessment pheromones.


Assuntos
Gafanhotos/fisiologia , Álcool Feniletílico/metabolismo , Atrativos Sexuais/metabolismo , Comportamento Sexual Animal , Animais , Aglomeração , Feminino , Fertilização , Masculino , Álcool Feniletílico/análise , Reprodução , Atrativos Sexuais/análise , Olfato
12.
Mol Phylogenet Evol ; 71: 224-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24071559

RESUMO

The Podismini are melanopline grasshoppers with a Holarctic distribution and well represented in the Eurasian fauna. To investigate their controversial taxonomy and evolutionary history, we studied 86%, 78% and 33% respectively of the Eurasian, European and Asian Palaearctic genera (Otte, 1995; Eades et al., 2013). We reconstructed parsimony, maximum likelihood and Bayesian phylogenies using fragments of four genes (ITS1, 16S, 12S, CO2). We applied a Bayesian molecular clock to estimate the times of species divergence, and the event-based parsimony method to depict the biogeographic framework of the diversification. Our results suggest that the selected Eurasian Podismini constitute a monophyletic group inside the Melanoplinae, provided it includes the North American genus Phaulotettix. The clades proposed by the present study inside the Podismini do not fit the older morphological or cytological classifications, but are in agreement with more recent proposals. Furthermore, our results can be explained by a plausible biogeographic history in which the present geographical distribution of the Eurasian Podismini resulted from known changes, to the Cenozoic climate and vegetation, induced by major geological events including the genesis of high mountain chains (e.g., Himalayas, Altay, Alps) and large deserts (e.g., Gobi, Karakoum, Taklamakan), and the opening of marginal seas (e.g., Bering, Japanese and Yellow Seas).


Assuntos
Gafanhotos/genética , Filogenia , Animais , Teorema de Bayes , Funções Verossimilhança , Filogeografia , Análise de Sequência de DNA
13.
Biodivers Data J ; 12: e115845, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481856

RESUMO

The migratory locust, Locustamigratoria (L.), a significant grasshopper species known for its ability to form large swarms and cause extensive damage to crops and vegetation, is subject to the influence of climate change. This research paper employs geographic information system (GIS) and MaxEnt ecological modelling techniques to assess the impact of climate change on the distribution patterns of L.migratoria. Occurrence data and environmental variables are collected and analysed to create predictive models for the current and future distribution of the species. The study highlights the crucial role of climate factors, particularly temperature and precipitation, in determining the locust's distribution. The MaxEnt models exhibit high-performance indicators, accurately predicting the potential habitat suitability of L.migratoria. Additionally, specific bioclimatic variables, such as mean temperature and annual precipitation, are identified as significant factors influencing the species' presence. The generated future maps indicate how this species will invade new regions especially in Europe. Such results predict the risk of this destructive species for many agriculture communities as a direct result of a warming world. The research provides valuable insights into the complex relationship between locust distribution and environmental factors, enabling the development of effective strategies for locust management and early warning systems to mitigate the impact on agriculture and ecosystems.

14.
Insects ; 14(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36662013

RESUMO

Clarifying phylogenetic position and reconstructing robust phylogeny of groups using various evidences are an eternal theme for taxonomy and systematics. In this study, the complete mitogenomes of Longzhouacris mirabilis, Ranacris albicornis, and Conophyma zhaosuensis were sequenced using next-generation sequencing (NGS), and the characteristics of the mitogenomes are presented briefly. The mitogenomes of the three species are all circular molecules with total lengths of 16,164 bp, 15,720 bp, and 16,190 bp, respectively. The gene structures and orders, as well as the characteristics of the mitogenomes, are similar to those of other published mitogenomes in Caelifera. The phylogeny of the main subfamilies of Acrididae with prosternal process was reconstructed using a selected dataset of mitogenome sequences under maximum likelihood (ML) and Bayesian inference (BI) frameworks. The results showed that the genus Emeiacris consistently fell into the subfamily Melanoplinae rather than Oxyinae, and the genus Choroedocus had the closest relationship with Shirackiacris of the subfamily Eyprepocnemidinae in both phylogenetic trees deduced from mitogenome protein coding genes (PCGs). This finding is entirely consistent with the morphological characters, which indicate that Emeiacris belongs to Melanoplinae and Choroedocus belongs to Eyprepocnemidinae. In addition, the genera Conophymacris and Xiangelilacris, as well as Ranacris and Menglacris, are two pairs of the closest relatives, but their phylogenetic positions need further study to clarify.

15.
Biodivers Data J ; 11: e96705, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327285

RESUMO

Background: Grasshoppers (Acridoidea, Orthoptera) are the dominant herbivores in grassland ecosystems worldwide. They can increase rangeland productivity by stimulating plant growth and accelerating nutrient cycling. This article presents a comprehensive checklist of grasshoppers in Mongolia. Until then, the available information was very scattered, based on old studies of Mongolian grasshoppers, recorded in a few international catalogues and databases, individual records and research work on agroecosystem communities. However, the available information on the composition of the Orthopteran fauna in Mongolia was sometimes unclear or non-existent and these dubious data were excluded from the present study. In addition, the grasshopper distribution analysis used the standardised personal collection of D. Altanchimeg. We also present a list of grasshoppers, as well as their distribution and abundance, in countries adjacent to Mongolia, such as Russia, China and South Korea. The surveys covered six types of natural zones: high mountain, taiga, forest-steppe, steppe, desert steppe and desert; desert steppe and steppe zones are the most widely distributed. We hope to have contributed significantly to the study of the distribution of grasshopper species in all these natural zones. New information: In this study, a total of three families of Acridoidea belonging to eight subfamilies, 17 tribes, 52 genera and 128 species are reported for the various natural zones. The recorded species belong to eight subfamilies: Gomphocerinae are the most numerous with 56 species recorded, followed by Oedipodinae (51 species), Thrinchinae (nine species), Melanoplinae (six species), Calliptaminae (three species), Dericorythinae, Acridinae, Egnatiinae (one species each).

16.
Mitochondrial DNA B Resour ; 7(4): 616-618, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35402711

RESUMO

The complete mitochondrial genome (mitogenome) of Sinopodisma hengshanica (Orthoptera: Acrididae) was firstly determined and analyzed in the present study. Assembled mitogenome sequence of S. hengshanica is 15,623 bp in size, containing 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), as well as one A + T-rich region. Its gene component and arrangement are identical with other Acrididae species. The overall nucleotide composition is as follows: A (42.89%), G (10.34%), T (33.07%), and C (13.70%). All PCGs are initiated by typical ATN codons, and terminated with harboring complete stop codons TAA and TAG. Furthermore, phylogenetic trees were reconstructed based on 13 PCGs to validate the taxonomic status of S. hengshanica, exhibiting a close relationship with Sinopodisma rostellocerca.

17.
J Parasitol ; 108(5): 487-499, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302369

RESUMO

Herein, we reaffirm the validity of Coronoepimeritus and its junior synonym, Quadruspinospora, provide new combinations for existing species of Quadruspinospora, recognize Monospinospora n. gen. to receive Coronoepimeritus monospinus, and describe Coronoepimeritus otoensis n. sp. from the alimentary canal of the admirable grasshopper, Syrbula admirabilis (Orthoptera: Acrididae), from Nemaha County (40°45'69.49″N, 95°71'60.39″W) near Peru, Nebraska. Our specimens differ from all known species by differences in total gamont length (TL), oocyst length (OL), and oocyst spine length (OSL). Coronoepimeritus atractomorphii n. comb. is most like the new species on the basis of OL and OSL (10 µm and 33 µm, respectively, for both species), but the new species possesses gamonts whose TL is less than 60% of that reported for C. atractomorphii (average TL, 703 µm vs. 1,020 µm, respectively). Nucleotide sequences (18S) and phylogenetic analyses confirm the placement of the new species in Coronoepimeritus, and the K/Θ test (the ratio between the average distance separating 2 species-level clades and the genetic diversity of these clades) is consistent with a species distinct from the only other known sequence sample in the group, Coronoepimeritus mexicana n. comb.


Assuntos
Gafanhotos , Animais , Filogenia , Oocistos , Peru
18.
Behav Ecol ; 33(1): 17-26, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35197804

RESUMO

Orthopteran insects are characterized by high variability in body coloration, in particular featuring a widespread green-brown color polymorphism. The mechanisms that contribute to the maintenance of this apparently balanced polymorphism are not yet understood. To investigate whether morph-dependent microhabitat choice might contribute to the continued coexistence of multiple morphs, we studied substrate choice in the meadow grasshopper Pseudochorthippus parallelus. The meadow grasshopper occurs in multiple discrete, genetically determined color morphs that range from uniform brown to uniform green. We tested whether three common morphs preferentially choose differently colored backgrounds in an experimental arena. We found that a preference for green backgrounds was most pronounced in uniform green morphs. If differential choices improve morph-specific performance in natural habitats via crypsis and/or thermoregulatory benefits, they could help to equalize fitness differences among color morphs and potentially produce frequency-dependent microhabitat competition, though difference appear too small to serve as the only explanation. We also measured the reflectance of the grasshoppers and backgrounds and used visual modeling to quantify the detectability of the different morphs to a range of potential predators. Multiple potential predators, including birds and spiders, are predicted to distinguish between morphs chromatically, while other species, possibly including grasshoppers themselves, will perceive only differences in brightness. Our study provides the first evidence that morph-specific microhabitat choice might be relevant to the maintenance of the green-brown polymorphisms in grasshoppers and shows that visual distinctness of color morphs varies between perceivers.

19.
Ecol Evol ; 11(10): 5413-5423, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34026017

RESUMO

We contrast the response of arthropod abundance and composition to bison grazing lawns during a drought and non-drought year, with an emphasis on acridid grasshoppers, an important grassland herbivore.Grazing lawns are grassland areas where regular grazing by mammalian herbivores creates patches of short-statured, high nutrient vegetation. Grazing lawns are predictable microsites that modify microclimate, plant structure, community composition, and nutrient availability, with likely repercussions for arthropod communities.One year of our study occurred during an extreme drought. Drought mimics some of the effects of mammalian grazers: decreasing above-ground plant biomass while increasing plant foliar percentage nitrogen.We sampled arthropods and nutrient availability on and nearby ("off") 10 bison-grazed grazing lawns in a tallgrass prairie in NE Kansas. Total grasshopper abundance was higher on grazing lawns and the magnitude of this difference increased in the wetter year of 2019 compared to 2018, when drought led to high grass foliar nitrogen concentrations on and off grazing lawns. Mixed-feeding grasshopper abundances were consistently higher on grazing lawns while grass-feeder and forb-feeder abundances were higher on lawns only in 2019, the wetter year. In contrast, the abundance of other arthropods (e.g., Hemiptera, Hymenoptera, and Araneae) did not differ on and off lawns, but increased overall in 2019, relative to the drought of 2018.Understanding these local scale patterns of abundances and community composition improves predictability of arthropod responses to ongoing habitat change.

20.
J Insect Physiol ; 134: 104296, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34411586

RESUMO

Olfaction plays an important role in the behavioural ecology of the desert locust Schistocerca gregaria (Orthoptera:Acrididae). Different locust life stages and sexes use olfactory cues for different behaviours such as grouping, mating, oviposition, feeding, maturation and gregarization, which can be exploited for management of the desert locust. However, the full spectrum of the chemistry of volatiles released by the desert locust remains unknown. Here, we compared the volatile emissions of different life stages of a natural wild population reared in the laboratory for one generation with those of a population that has been reared in the laboratory for seven generations. Coupled gas chromatography-mass spectrometric analysis was used to identify captured volatiles. Analysis of similarities (ANOSIM) and non-metric multidimensional scaling of the volatile organic compounds (VOCs) showed significant chemo-diversity between different life stages, and sexes for the adults of the two populations. Additionally, chemical analysis showed that nymphs and adults of the field population released ~4- to 40-fold more volatiles, and they were compositionally richer than their laboratory counterparts. These results demonstrate the composition and variation in odors of field and laboratory populations of the desert locust, and that the discriminating odors warrant further investigation to determine their roles in the bioecology and management of this locust species.


Assuntos
Comportamento Animal , Gafanhotos , Compostos Orgânicos Voláteis/metabolismo , Animais , Comportamento Animal/fisiologia , Gafanhotos/metabolismo , Gafanhotos/fisiologia , Controle de Insetos , Laboratórios , Odorantes , Densidade Demográfica , Olfato/fisiologia
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