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1.
Ecotoxicol Environ Saf ; 211: 111869, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33450537

RESUMO

Solitary bees are among the most important pollinators worldwide however population declines especially in croplands has been noticed. The novel pesticide sulfoxaflor is a competitive modulator of nicotinic acetylcholine receptors (nAChR) in insects. While there is evidence of a negative impact of neonicotinoids on bees of several social organization levels, our overall knowledge on the impact of sulfoxaflor on bees is poor. Here we present for the first time a study showing effects of field realistic doses of sulfoxaflor on solitary bees. Bees submitted to long term exposure of field realistic doses of sulfoxaflor (5 µg dm-3, 10 µg dm-3, 50 µg dm-3) and control were observed regarding their survival rate. Moreover, we recorded metrics related to flower visitation and flight performance. We discover that the highest field realistic dose is lethal to Osmia bicornis along five days of exposure. The effect of sulfoxaflor reduces the outcome of foraging, important features for fruit and seed production of cross-pollinated plant species. Bees exposed to pesticide visited flowers mostly walking rather than flying. Flight performance was also impaired by the pesticide.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Animais , Comportamento Alimentar/efeitos dos fármacos , Flores/efeitos dos fármacos , Neonicotinoides/toxicidade , Praguicidas/toxicidade , Polinização/efeitos dos fármacos , Piridinas , Compostos de Enxofre , Taxa de Sobrevida
2.
An Acad Bras Cienc ; 92(suppl 2): e20190745, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33174912

RESUMO

Differences in species composition between sites (ß diversity) may be the result of spatial species replacement (turnover) or nestedness (subgroups of species from a more diverse site). In fragmented landscapes, the environmental factors that lead to these differences may be spatially structured. Herein, our objective is to determine if the ß diversity of Chrysomelidae (Coleoptera) is due to turnover or nestedness and whether the observed pattern is due to loss of forest cover or spatial processes in forest remnants immersed in a matrix dominated by intense agricultural practice. We used an incidence matrix of 99 species sampled from 16 forest remnants and found that the difference in species composition among the fragments is mostly determined by turnover and that this variation is not explained by forest cover or spatial variables. In regions where high habitat loss has generated landscapes containing small and islated forest fragments, structural features, related both to habitat (area, isolation, shape, etc.) and landscape (land use, landscape heterogeneity, etc.) could predict diversity patterns.


Assuntos
Besouros , Agricultura , Animais , Biodiversidade , Ecossistema , Florestas
3.
Insects ; 11(7)2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32635667

RESUMO

Environmental quality (e.g., diversity of resource availability, nesting sites, environmental display) plays an important role in an animal's life. While homogeneous environments can restrict organisms from developing activities such as food seeking (behavioral impairment), more complex environments allow animals to perform activities with learning and behavioral perfecting outcomes. Pesticides are known to affect the learning and foraging behaviors of bees; however, little is known about the counterbalance displayed by the environment. Herein, we conducted two experiments that simulated distinct environmental displays, in which the effects of a fungicide (IndarTM 5EW-febunconazole) on solitary bee foraging activities were tested. We found that the fungicide only impaired the activities of bees in one of the studied environments. The difference in visitation rates and flower exploitation of bees between the two different environmental displays led to changes in metrics of bee-flower networks across environments. Linkage density, a metric associated with pollination efficiency that is known to be impacted by different environments, differed across environments. Our results showed that ecological interaction network metrics can differ regarding the different environmental displays. This study indicates that environmental complexity helps balance the negative effects of pesticides on solitary bees and highlights the potential use of solitary bees as model organisms for experimental simulations of environmental change.

4.
Environ Entomol ; 48(5): 1095-1103, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31287500

RESUMO

Insect-resistant genetically modified (GM) plants have been cultivated in several countries on a large scale. These plants express the Cry toxins from the bacterium Bacillus thuringiensis Berliner (Bacillales: Bacillaceae) (Bt), which confers target-pest resistance to plants. Studies on the effects of GM plants on nontarget organisms are important to assess the technology's impact on biodiversity. The objective of this study was to determine whether there are differences in the species richness and composition of ants and ground beetles in Bt maize (four different toxins: Cry1Ab, Cry1F, and Cry1A.105/Cry2Ab2) and conventional isoline (non-Bt) fields, in the first (summer) and second (winter) cropping seasons in 13 localities of Mato Grosso do Sul State, Brazil, over a 2-yr period (2009-2011). The assessment of Coleoptera and Formicidae species was performed using pitfall traps placed in fields throughout the period of vegetative growth and maturation of plants. Data were analyzed using faunistic indices of species richness, ordination by nonmetric multidimensional scaling, and multivariate analysis of variance. No statistically significant difference was found in the species richness of ant and ground beetle communities when comparing sites of Bt with those of non-Bt maize. Overall, Bt technology did not affect the composition of ant and ground beetles; however, municipality and cropping season exerted influence on the beetle composition. Some species were only observed in the first crop, whereas others were only observed in the second crop. This research suggests that Bt maize does not affect ant and ground beetle populations differently from its isoline.


Assuntos
Formigas , Bacillus thuringiensis , Besouros , Animais , Proteínas de Bactérias , Brasil , Endotoxinas , Proteínas Hemolisinas , Plantas Geneticamente Modificadas , Zea mays
5.
Ecotoxicol Environ Saf ; 164: 548-553, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30149353

RESUMO

Throughout evolutionary history bees have developed complex communication systems. For social bees, communication is important for both the individual and the development of the colony. Successful communication helps bees to recognize relatives, defend the colony, and promote recruitment to optimize foraging of floral resources. Bees' contribution to pollination is of broad environmental and economic importance. However, studies have reported that anthropogenic actions, such as the use of pesticides, negatively affect bee survival and behavior. We tested the effect of a commercially available pesticide mix containing two pesticide classes, a neonicotinoid and a pyrethroid, on the social behavior of the stingless bee, Melipona quadrifasciata (Lepeletier, 1863). After determining a sublethal dose of the pesticides, we tested the effect of an acute dose on antennation and trophallaxis behaviors of worker bees. Our results showed a drastic reduction in the communication and social interactions of bees.


Assuntos
Abelhas/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Praguicidas/toxicidade , Piretrinas/toxicidade , Comportamento Social , Comunicação Animal , Animais , Exposição Ambiental , Polinização
6.
Iheringia Ser. Zool. ; 107(Supl.): e2017109, 2017.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15521

RESUMO

Nós compilamos uma lista de espécies de aranhas registradas no Mato Grosso do Sul (Brasil) a partir da literatura taxonômica e de inventários não publicados. A lista inclui 228 espécies em 134 gêneros e 32 famílias. Apenas cerca de 35% da área do estado apresenta registros de ocorrência de espécies de aranhas, e não mais que 5% apresenta mais de um registro de ocorrência por quadrícula de 0,5° (˜2.916 km2). Existem grandes lacunas de amostragem no estado, particularmente na porção norte do Pantanal. A maioria das espécies tem menos de 10 registros de ocorrência, ou seja, sua distribuição geográfica é praticamente desconhecida. Extrapolando a curva de acumulação de espécies dessas aranhas, concluímos que seria necessário ampliar em 10 vezes a área amostrada para que sejam listadas 90% das espécies que ocorrem no estado. Número de espécies: no mundo, 44.906; no Brasil, 3.730; no Mato Grosso do Sul, 228. Portanto, novos inventários são essenciais para que a araneofauna do Mato Grosso do Sul seja minimamente conhecida.


Here we compile a list of spider species recorded in Mato Grosso do Sul state (Brazil), based on information from the taxonomic literature and unpublished inventories. The list includes 228 species in 134 genera and 32 families. Only approximately 35% of the state area have records of spider species, and no more than 5% of the area presents more than one record per 0.5° grid cell (˜2,916 km2). There are large gaps in the knowledge of the state’s spider fauna, particularly in the northern Pantanal. Most of the species are known by less than 10 distribution records, indicating that their geographic distribution is virtually unknown. Extrapolating a species accumulation curve, we show that a ten-time increase in sampled area would be necessary to discover 90% of the species occurring in the state. Number of species: in the world, 44,906; in Brazil, 3,730; in Mato Grosso do Sul, 228. Therefore new inventories are essential for an adequate description of the spider fauna of the state of Mato Grosso do Sul.

7.
Iheringia Ser. Zool. ; 107(Supl.): e2017108, 2017.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15519

RESUMO

Nesse artigo é fornecida uma lista de espécies de Scorpiones do estado do Mato Grosso do Sul, Brasil. Até o momento 16 espécies e uma subespécie não-nominotípica estão registradas para o estado, porém é discutida a presença e/ou o status taxonômico de três destas espécies. Assim, considera-se que a escorpiofauna do Mato Grosso do Sul é composta, até o momento, por 13 espécies, o que representa mais de 50% de todas as espécies de escorpiões conhecidas para o Centro-Oeste brasileiro. Duas espécies de bothriurídeos são conhecidas apenas para este estado e consideradas endêmicas Bothriurus pora Mattoni & Acosta, 2005 e Brazilobothriurus pantanalensis Lourenço & Monod, 2000. A distribuição dos registros de escorpiões no Mato Grosso do Sul é heterogênea, uma vez que as áreas dominadas por Mata Atlântica e pelo Pantanal são menos amostradas em relação àquelas de domínios do Cerrado.


In this paper it is provided a checklist of Scorpiones species in the state of Mato Grosso do Sul, Brazil. There are 16 species and one non-nominotypical subspecies recorded for the state, although it is discussed the presence and/or the taxonomic status of three of these species. This, it is considered that the scorpiofauna of the Mato Grosso do Sul is actually composed of 13 species, which represents more than 50% of all known species from Central-western Brazil. Two bothriurid species are known only for this state and are considered endemics: Bothriurus pora Mattoni & Acosta, 2005 and Brazilobothriurus pantanalensis Lourenço & Monod, 2000. The distribution of the scorpion registries in the Mato Grosso do Sul is heterogeneous, being the areas dominated by Atlantic Forest and Pantanal is sampled worse than those covered by the Cerrado domains.

8.
Mem. Inst. Oswaldo Cruz ; 110(4): 551-559, 09/06/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748859

RESUMO

This study updates the geographic distributions of phlebotomine species in Central-West Brazil and analyses the climatic factors associated with their occurrence. The data were obtained from the entomology services of the state departments of health in Central-West Brazil, scientific collections and a literature review of articles from 1962-2014. Ecological niche models were produced for sandfly species with more than 20 occurrences using the Maxent algorithm and eight climate variables. In all, 2,803 phlebotomine records for 127 species were analysed. Nyssomyia whitmani, Evandromyia lenti and Lutzomyia longipalpis were the species with the greatest number of records and were present in all the biomes in Central-West Brazil. The models, which were produced for 34 species, indicated that the Cerrado areas in the central and western regions of Central-West Brazil were climatically more suitable to sandflies. The variables with the greatest influence on the models were the temperature in the coldest months and the temperature seasonality. The results show that phlebotomine species in Central-West Brazil have different geographical distribution patterns and that climate conditions in essentially the entire region favour the occurrence of at least one Leishmania vector species, highlighting the need to maintain or intensify vector control and surveillance strategies.


Assuntos
Animais , Insetos Vetores/classificação , Phlebotomus/classificação , Distribuição Animal , Brasil , Clima , Leishmaniose/transmissão , Densidade Demográfica , Estações do Ano
9.
Mem Inst Oswaldo Cruz ; 110(4): 551-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26018450

RESUMO

This study updates the geographic distributions of phlebotomine species in Central-West Brazil and analyses the climatic factors associated with their occurrence. The data were obtained from the entomology services of the state departments of health in Central-West Brazil, scientific collections and a literature review of articles from 1962-2014. Ecological niche models were produced for sandfly species with more than 20 occurrences using the Maxent algorithm and eight climate variables. In all, 2,803 phlebotomine records for 127 species were analysed. Nyssomyia whitmani, Evandromyia lenti and Lutzomyia longipalpis were the species with the greatest number of records and were present in all the biomes in Central-West Brazil. The models, which were produced for 34 species, indicated that the Cerrado areas in the central and western regions of Central-West Brazil were climatically more suitable to sandflies. The variables with the greatest influence on the models were the temperature in the coldest months and the temperature seasonality. The results show that phlebotomine species in Central-West Brazil have different geographical distribution patterns and that climate conditions in essentially the entire region favour the occurrence of at least one Leishmania vector species, highlighting the need to maintain or intensify vector control and surveillance strategies.


Assuntos
Insetos Vetores/classificação , Phlebotomus/classificação , Distribuição Animal , Animais , Brasil , Clima , Leishmaniose/transmissão , Densidade Demográfica , Estações do Ano
10.
Mem. Inst. Oswaldo Cruz ; 108(8): 992-996, 6/dez. 2013. graf
Artigo em Inglês | LILACS | ID: lil-697138

RESUMO

To understand the geographic distribution of visceral leishmaniasis (VL) in the state of Mato Grosso do Sul (MS), Brazil, both the climatic niches of Lutzomyia longipalpis and VL cases were analysed. Distributional data were obtained from 55 of the 79 counties of MS between 2003-2012. Ecological niche models (ENM) of Lu. longipalpis and VL cases were produced using the maximum entropy algorithm based on eight climatic variables. Lu. longipalpis showed a wide distribution in MS. The highest climatic suitability for Lu. longipalpis was observed in southern MS. Temperature seasonality and annual mean precipitation were the variables that most influenced these models. Two areas of high climatic suitability for the occurrence of VL cases were predicted: one near Aquidauana and another encompassing several municipalities in the southeast region of MS. As expected, a large overlap between the models for Lu. longipalpis and VL cases was detected. Northern and northwestern areas of MS were suitable for the occurrence of cases, but did not show high climatic suitability for Lu. longipalpis . ENM of vectors and human cases provided a greater understanding of the geographic distribution of VL in MS, which can be applied to the development of future surveillance strategies.


Assuntos
Animais , Humanos , Insetos Vetores/classificação , Psychodidae/classificação , Brasil , Clima , Geografia Médica , Leishmaniose Visceral/transmissão , Densidade Demográfica , Estações do Ano
11.
Mem Inst Oswaldo Cruz ; 108(8): 992-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24402151

RESUMO

To understand the geographic distribution of visceral leishmaniasis (VL) in the state of Mato Grosso do Sul (MS), Brazil, both the climatic niches of Lutzomyia longipalpis and VL cases were analysed. Distributional data were obtained from 55 of the 79 counties of MS between 2003-2012. Ecological niche models (ENM) of Lu. longipalpis and VL cases were produced using the maximum entropy algorithm based on eight climatic variables. Lu. longipalpis showed a wide distribution in MS. The highest climatic suitability for Lu. longipalpis was observed in southern MS. Temperature seasonality and annual mean precipitation were the variables that most influenced these models. Two areas of high climatic suitability for the occurrence of VL cases were predicted: one near Aquidauana and another encompassing several municipalities in the southeast region of MS. As expected, a large overlap between the models for Lu. longipalpis and VL cases was detected. Northern and northwestern areas of MS were suitable for the occurrence of cases, but did not show high climatic suitability for Lu. longipalpis. ENM of vectors and human cases provided a greater understanding of the geographic distribution of VL in MS, which can be applied to the development of future surveillance strategies.


Assuntos
Insetos Vetores/classificação , Psychodidae/classificação , Animais , Brasil , Clima , Geografia Médica , Humanos , Leishmaniose Visceral/transmissão , Densidade Demográfica , Estações do Ano
12.
J Insect Sci ; 12: 21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22954231

RESUMO

The division of labor between castes and the division of labor in workers according to age (temporal polyethism) in social wasps are crucial for maintaining social organization. This study evaluated the division of labor between castes, and the temporal polyethism in workers of Mischocyttarus consimilis Zikán (Hymenoptera: Vespidae). To describe the behavioral repertory of this species, observations were made of 21 colonies, with 100 hours of observations. In order to observe temporal polyethism, each newly emerged wasp was marked with colored dots on the upper area of the thorax. This allowed the observation of behavioral acts performed by each worker from the time of emergence to its death. Through hybrid multidimensional scaling, a clear division between queens and workers could be identified, in which the behaviors of physical dominance and food solicitation characterized the queen caste; while behaviors such as adult-adult trophallaxis, destruction of cells, alarm, foraging for prey, foraging for nectar, and unsuccessful foraging characterized the worker caste. Hybrid multidimensional scaling characterized two groups, with intra-nest activities preferentially accomplished by younger workers, while extra-nest activities such as foraging were executed more frequently by older workers.


Assuntos
Comportamento Animal , Vespas/fisiologia , Fatores Etários , Animais , Evolução Biológica , Brasil , Comportamento Alimentar , Feminino , Dinâmica Populacional , Reprodução , Comportamento Social
13.
Journal of Arachnology ; 39(3): 537-540, 2011.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1064196

RESUMO

The presence of buds, flowers, and fruits increases structural complexity in plants, but can also attract potentialprey for predators, thus determining faunistic composition. To understand how a spider assemblage living in the shrub Byrsonima intermedia (Malpighiaceae) varies with habitat structure in terms of reproductive elements and height of plant,we collected spider specimens and measured bud, flower, fruit, and leaf masses of 44 plants, as well as their height. Spider family composition was found to depend on habitat structure, following a pattern of family turnover occurring along gradients of reproductive plant elements and height, regardless of plant biomass. Theridiidae occurred in samples with themajor proportions of buds and flowers, while Oxyopidae occurred only in samples with major proportions of fruits.Multiple linear regression revealed the strong relation between the composition in reproductive plant elements and thecomposition in families of spiders and a relation between shrub height and spider family composition. These results help us to understand the temporal dynamics between structural complexity of vegetation and spider assemblages, because during plant phenology the proportions of reproductive elements are also varying.


Assuntos
Animais , Aranhas/classificação , Aranhas/crescimento & desenvolvimento , Ecossistema/análise , Malpighiaceae
14.
Braz. arch. biol. technol ; 51(6): 1199-1207, Nov.-Dec. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-504042

RESUMO

This study had the objective of assessing the differences in foraging activity of the predacious ants between two areas, one conventional and other with no-till agriculture systems. The research was conducted in two contiguous 1.5 ha plots in Dourados MS, Brazil, from February 2001 to December 2003. Each plot received 750 baits (Nasutitermes termites), 425 at daylight and 325 at night. The termites were placed on the filter paper, on the ground, and ant attack was monitored for 15 min, until removed. Sixteen ant species were found in the no-till system and nine in the conventional system. Baits removed from no-till were significantly higher than the conventional plots and were influenced by the sampling time, at day or night. The seasons of the year did not significantly explain the variations in the structure of the predacious ant communities in neither of the systems. The significant differences at foraging activity and ant richness between the areas indicated that the no-tillage system could improve environmental quality of the cropping and therefore, became an important tool for the integrated pest management programs.


O objetivo do trabalho foi avaliar se a atividade de forrageamento de formigas predadoras em agroecossistemas varia entre duas áreas, uma com sistema de cultivo direto e outra com cultivo convencional. A pesquisa foi realizada em Dourados, MS, de fevereiro de 2001 a dezembro de 2003 em duas áreas contíguas de 1,5 ha cada. Como isca utilizou-se cupins do gênero Nasutitermes. Em cada área foram colocadas 750 iscas, sendo 425 durante o dia e 325 à noite. Cada cupim permanecia exposto sobre o solo por 15 minutos, ou até ser atacado. Foram encontradas 16 espécies de formigas no plantio direto e nove no convencional. A proporção de iscas retiradas por formigas no plantio direto (167 de 750) e convencional (97 de 750) dependeu do turno de amostragem. Nos dois turnos a proporção de iscas removidas por formigas foi significativamente maior no plantio direto. As estações do ano não explicaram significativamente as variações na estrutura da comunidade de formigas nas áreas. As variações observadas em atividade de forageamento e em riqueza de espécies de formigas predadoras entre as duas áreas que diferiam em sistema de cultivo, indicam que o sistema de cultivo direto acrescentou uma melhora ambiental, tornando-se assim uma importante ferramenta para programas de manejo integrado de pragas.

15.
Biota neotrop. (Online, Ed. port.) ; 5(1a): 125-140, 2005. graf, tab
Artigo em Português | LILACS-Express | LILACS, Sec. Est. Saúde SP | ID: lil-459537

RESUMO

As aranhas são excelentes objetos de estudo para a avaliação da organização das comunidades animais e da influência do hábitat sobre estas comunidades. Contudo, para o entendimento da organização de uma dada comunidade é preciso o registro dos seus componentes (espécies). Para tanto, foi feito um levantamento das espécies de aranhas na região das cabeceiras da Bacia do Rio Paraguai. Foram realizadas coletas sistemáticas (guarda-chuva entomológico e transecto noturno) e ocasionais. Este esforço de coleta permitiu a descoberta de pelo menos 16 novas espécies, além do registro de 39 novas ocorrências de espécies para o estado do Mato Grosso. Foram coletadas 2114 aranhas (601 adultas), agrupadas em 206 morfoespécies de 35 famílias (sete apenas com indivíduos imaturos) e 105 gêneros, sendo que as estimativas estatísticas apontam para a existência de 290 espécies na área. As famílias mais ricas em espécies foram Araneidae (51 espécies), Theridiidae (46 spp.) e Salticidae (36 spp.), que representam juntas mais de 65 por cento das espécies registradas. A estrutura da comunidade apresenta alto número de espécies e baixo número de indivíduos por espécie, o que é característico de comunidades tropicais de aranhas. Comparando-se a distribuição das espécies no pantanal e na Amazônia Legal, vê-se que a influência amazônica existe já em localidades mais ao sul, como Cáceres (47 por cento fauna amazônica), aumentando progressivamente à medida que se prossegue para o norte (Indiavaí - 75 por cento; Reserva do Cabaçal - 82 por cento; Jauru - 86 por cento).


Spiders are good study subjects when it comes to the evaluation of animal community organization and of the habitat's influence over it. Nevertheless, the first step to understand the organization of a specific community is to record its species. An inventory of the spider fauna of the headwaters of the Paraguay River basin was carried out using systematic (beating tray and nocturnal transects) and casual samplings. As a result, at least 16 new species, as well as 39 new occurrences for the state of Mato Grosso were recorded. A total of 2114 spiders (602 of them adults), distributed among 206 morphospecies (35 families and 105 genera) were collected. Statistical estimates point towards the existence of a much larger number of spider species (at least 290) in the sampled areas. Together, Araneidae, Theridiidae and Salticidae, the most species rich families (51, 46 and 36 spp., respectively), represent more than 65 percent of the overall spider richness. A high number of species and a low number of individuals per species characterize community structure, a result that is typical for tropical spider communities. Amazonian influence, as depicted from faunal comparisons between species composition at Pantanal and Legal Amazonia, increases continuously from more southern localities, such as Cáceres (47 percent amazonian fauna) to northern localities, such as Indiavaí (75 percent), Reserva do Cabaçal (82 percent) or Jauru (86 percent).

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