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ABSTRACT The significant role of Aedes aegypti as a vector of several arboviruses has intensified studies on vector control tools, including Attractive Toxic Sugar Baits containing Pyriproxyfen (ATSB-PPF). PPF is an insect growth regulator (IGR) that has been used to control immature mosquitoes, but it also has direct effects on female reproduction. This study evaluated the effect of physical exposure of Ae. aegypti females with ATSB-PPF on fecundity and fertility at different times before and after blood meal. Females were confined in cages impregnated with ATSB-PPF at different concentrations (5, 50, and 500 ppm). One group of females was exposed to the baits 24 and 48 hours Before the Blood Meal (BBM), and in the other group, exposure occurred 24 and 48 hours After the Blood Meal (ABM). The number of eggs laid, larvae, and pupation rate were analyzed. Exposure of Ae. aegypti females to ATSB-PPF bait 24 hours after the blood meal was able to reduce the number of eggs laid, especially at the higher concentrations used, but the number of larvae obtained was reduced regardless of the exposure time to ATSB-PPF, i.e., 24 hours before or after the blood meal, or the concentration of PPF used. No changes were observed in the number of pupae from larvae obtained from eggs laid by mosquitoes exposed to ATSB-PPF. Physical exposure of mosquitoes to sugar baits is sufficient to reduce the investigated reproductive parameters of Ae. aegypti.

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The maintenance of the symbiosis between leaf-cutting ants and their mutualistic fungus Leucoagaricus gongylophorus Singer (Moller) is vital for the survival of both species. The specialist fungal parasite Escovopsis weberi Muchovej & Della Lucia is a threat to this symbiosis, causing severe damage to the fungal garden. Mycelial pellets are resistant fungal structures that can be produced under laboratory conditions. These structures were studied for use in biological pest control, but the production of mycelial pellets has not previously been documented in Escovopsis. One of the aims of this study was to induce Escovopsis weberi to produce mycelial pellets and investigate the potential of these pellets for the control of leaf-cutting ants. We compared the pathogenicity of Escovopsis weberi mycelial pellets and conidia against mini-colonies of Acromyrmex subterraneus subterraneus Forel when applied in the form of baits. Worker ants were able to distinguish mycelial pellets from conidia, as baits with mycelial pellets were more attractive to workers than those with conidia, causing a greater negative impact on colony health. All types of baits containing Escovopsis weberi influenced the foraging activity but only treatments with viable fungal propagules resulted in an increase in the quantity of waste material, with a significant negative impact on the fungal garden biomass. The results provided novel information regarding Escovopsis recognition by worker ants and differences between conidia and mycelial pellet dynamics in leaf-cutting ant colonies, with new perspectives for the biological control of these important pests.

RESUMO

Males of euglossine bees, also known as orchid bees, are attracted to aromatic compounds and this feature has been exploited to collect them. Here we sampled orchid bee males using a rapid passive method in a Neotropical savanna ecosystem in Rio Preto State Park (PERP), southeastern Brazil. The sampling protocol consisted of 5-day surveys using scent traps at the beginning and end of the rainy seasons. PERP is inserted in a Brazilian savanna characterized by a mosaic of vegetation types, and elevational gradients. We also analyzed whether the habitat complexity and elevational gradients influence the richness and abundance of these bees. We collected a total of 996 individuals belonging to 14 species and four genera (Eufriesea Cockerell 1908, Euglossa Latreille 1802, Eulaema Lepeletier 1841, and Exaerete Hoffmannsegg 1817). Comparing our results with previous sampling protocols at PERP, higher abundance and richness were observed using traps than insect nets to survey these bees. In addition, the orchid bee fauna in PERP was successfully assessed by our rapid passive protocol, showing that this protocol seems to be useful for collecting orchid bees in open vegetation environments. We observed that the abundance of bees was lower at higher elevations, and both abundance and richness increased in more complex habitat. This may be due to the characteristics of Brazilian savannas where the lower elevations have higher habitat complexity, with more places for nest construction and resources for feeding and nesting.

Assuntos

RESUMO

Ants (Hymenoptera: Formicidae), especially the Argentine ant, Linepithema humile (Mayr), can be significant nuisance pests in urban and suburban environments. Conventional interventions have primarily relied on the use of chemical insecticides, namely fipronil and bifenthrin, applied as residual, contact treatments around the outside perimeter of infested structures. Despite tightening regulation limiting the scope of insecticide applications in urban settings, dependence on these products to manage ants continues, resulting in significant water contamination. The U.S. EPA, in response, has further restricted the use patterns of many insecticides used for ant control in professional and over-the-counter markets. The purpose of this review is to summarize the relevant literature associated with controlling nuisance pest ants, with emphasis on L. humile, without the use of liquid broadcast applications of EPA-registered insecticides while focusing on low-impact, alternative (to broadcast applications) pest control methods. Specific subsections include Trail Pheromone; Use of Behavior-Modifying Chemicals; Mass Trapping; Hydrogels, "Virtual" Baiting, and Exceedingly-Low Bait Concentrations; Food Source Reduction; Deterrents; and RNA Interference (RNAi).

RESUMO

Biting midges are of interest to public health because they play an important role as vectors of disease-causing pathogens, as well as being a biting nuisance to humans and domestic animals. Although these insects are common in mangrove areas, they have not yet been studied in this ecosystem in the state of Maranhão (MA), Brazil. The objective of this study was to characterize the Culicoides community structure found in a mangrove swamp and verify if the use of vertebrate feces as bait interferes with their composition, richness, abundance, or seasonality. CDC light traps with vertebrate (chicken, ox, control, donkey, capuchin monkey and pig) feces baits were used to capture biting midges in a mangrove area of the Island of São Luís, MA. A total of 4,087 individuals representing 22 species of Culicoides were captured, the most abundant being C. (Oecacta) furens Poey (23.46%), C. (gr. Fluviatilis) leopoldoi Ortiz (21.58%), C. (Hoffmania) ignacioi Forattini (16.98%), C. (Hoffmania) maruim Lutz (13.85%), C. (Diphaomyia) iriartei Fox (10.57%), C. (Hoffmania) insignis Lutz (7.07%), and C. (gr. Limai) limai Barreto (3.03%). Species richness and abundance were higher when baits of capuchin monkey (15 species; 26.84% of the individuals) and pig (15; 25.3%) feces were used. The least attractive baits were donkey (12 species; 9.3%) and ox (nine species; 11.52%) feces. Biting midges were more abundant in the rainy season (67%), but richness was higher in the dry season (19 species). These results show that vertebrate feces may serve as olfactory cues and increase the attraction of biting midges to traps.

Assuntos

RESUMO

Field studies in forensic entomology seem to assume that a cadaver is a resource equally accessible to flies, irrespective of the species' size, behavior, and sensorial capacity. We aimed to challenge this assumption by experimentally manipulating baited traps in order to test whether the accessibility to decomposing baits is related to the following: (i) the diversity of necrophagous dipterans; (ii) the body size of adults; and (iii) the female sexual maturity stage. The experiment was performed in a rainforest fragment in Northeastern Brazil, in an area characterized by high levels of homicides. Traps baited with decomposing chicken liver had three levels of access: easy (six openings on the trap), intermediate (three), and difficult (one). A total of 750 adults of Calliphoridae, Fanniidae, Muscidae, Phoridae, and Sarcophagidae were collected. Of the 18 species recorded, Megaselia scalaris was the most abundant (46.8%) followed by Lucilia eximia (29.7%) and Chrysomya megacephala (9.8%). The number of species increased significantly with the accessibility level, but overall abundance did not differ, as a consequence of the numerical dominance of M. scalaris. A strong female bias (>91%) was observed in all traps. For Calliphoridae specimens, 90% of the females caught in traps under intermediate and difficult access were sexually mature. By empirically demonstrating that limitation of access and exclusion of visual stimuli do not deter several dipteran species from reaching a substrate, we expand the knowledge on the factors that can shape the colonization of concealed human cadavers, including variables such as insect size and stage of sexual maturity.

Assuntos

RESUMO

Abstract The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.

Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como "centros de endemismo". Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.

Assuntos

RESUMO

The distribution of most species occurs in delimited regions with unique characteristics called centers of endemism. In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70s. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.(AU)

A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como centros de endemismo. Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.(AU)

Assuntos

RESUMO

The effect of catch-and-release fishing on the survival of peacock bass (Cichla spp.) was evaluated by comparing two types of artificial bait (jig and shallow-diver plugs) and two types of post-catch confinement. Two experiments were conducted during the periods January-February and October-November 2012 in the Unini River, a right-bank tributary of the Negro River. In total, 191 peacock bass were captured. Both groups of fish were subjected to experimental confinement (collective and individual) for three days. Additionally, 11 fish were tagged with radio transmitters for telemetry monitoring. Mortality rate was estimated as the percentage of dead individuals for each type of bait and confinement. For peacock bass caught with jig baits, mortality was zero. The corresponding figure for shallow-diver bait was 1.66% for fish in collective containment, 18.18% for fish monitored by telemetry and 0% for individuals confined individually. Our results show low post-release mortality rates for peacock bass. Furthermore, neither the type of confinement nor the type of bait had a statistically significant influence on mortality rates. While future studies could include other factors in the analysis, our results show that catch-and-release fishing results in low mortality rates.(AU)

O efeito do pesque-solte na sobrevivência do tucunaré (Cichla spp.) foi avaliado comparando dois tipos de iscas artificiais, jig e de meia-água, e dois tipos de confinamento pós-captura. Dois experimentos foram conduzidos durante os períodos de janeiro-fevereiro e outubro-novembro de 2012, no Rio Unini, afluente da margem direita do Rio Negro. No total, 191 tucunarés foram capturados. Os peixes foram submetidos a um confinamento experimental (coletivo e individual) com duração de três dias. Além disso, 11 peixes foram marcados com radiotransmissores e liberados imediatamente após a captura, sendo monitorados por telemetria. A taxa de mortalidade foi calculada como a porcentagem de indivíduos mortos para cada tipo de isca e tratamento (confinamento individual, coletivo e sem confinamento). Não houve mortalidade para o grupo de tucunarés capturados com isca jig. A isca de meia-água mostrou uma taxa de mortalidade de 1,66% para o confinamento coletivo e 18,18% para os peixes monitorados por telemetria. Nossos resultados mostraram baixas taxas de mortalidade pós-soltura para tucunaré. Além disso, nem o tipo de confinamento, nem o tipo de isca tiveram influência significativa nas taxas de mortalidade. Ainda que estudos futuros possam incluir novos fatores na análise, os nossos resultados mostram que a prática do pesque-solte resulta em baixas taxas de mortalidade.(AU)

Assuntos

RESUMO

Abstract The effect of catch-and-release fishing on the survival of peacock bass (Cichla spp.) was evaluated by comparing two types of artificial bait (jig and shallow-diver plugs) and two types of post-catch confinement. Two experiments were conducted during the periods January-February and October-November 2012 in the Unini River, a right-bank tributary of the Negro River. In total, 191 peacock bass were captured. Both groups of fish were subjected to experimental confinement (collective and individual) for three days. Additionally, 11 fish were tagged with radio transmitters for telemetry monitoring. Mortality rate was estimated as the percentage of dead individuals for each type of bait and confinement. For peacock bass caught with jig baits, mortality was zero. The corresponding figure for shallow-diver bait was 1.66% for fish in collective containment, 18.18% for fish monitored by telemetry and 0% for individuals confined individually. Our results show low post-release mortality rates for peacock bass. Furthermore, neither the type of confinement nor the type of bait had a statistically significant influence on mortality rates. While future studies could include other factors in the analysis, our results show that catch-and-release fishing results in low mortality rates.

Resumo O efeito do pesque-solte na sobrevivência do tucunaré (Cichla spp.) foi avaliado comparando dois tipos de iscas artificiais, jig e de meia-água, e dois tipos de confinamento pós-captura. Dois experimentos foram conduzidos durante os períodos de janeiro-fevereiro e outubro-novembro de 2012, no Rio Unini, afluente da margem direita do Rio Negro. No total, 191 tucunarés foram capturados. Os peixes foram submetidos a um confinamento experimental (coletivo e individual) com duração de três dias. Além disso, 11 peixes foram marcados com radiotransmissores e liberados imediatamente após a captura, sendo monitorados por telemetria. A taxa de mortalidade foi calculada como a porcentagem de indivíduos mortos para cada tipo de isca e tratamento (confinamento individual, coletivo e sem confinamento). Não houve mortalidade para o grupo de tucunarés capturados com isca jig. A isca de meia-água mostrou uma taxa de mortalidade de 1,66% para o confinamento coletivo e 18,18% para os peixes monitorados por telemetria. Nossos resultados mostraram baixas taxas de mortalidade pós-soltura para tucunaré. Além disso, nem o tipo de confinamento, nem o tipo de isca tiveram influência significativa nas taxas de mortalidade. Ainda que estudos futuros possam incluir novos fatores na análise, os nossos resultados mostram que a prática do pesque-solte resulta em baixas taxas de mortalidade.

Assuntos

RESUMO

Dung beetles are globally used in ecological research and are useful for assessing the effects of anthropic and natural changes in environment on biodiversity. Here we investigate how the choice of baits (human feces, cattle dung, carrion or a combination of all three) and sampling season influence the taxonomic and functional diversity of insects captured in traps in Brazilian pastures. We sampled dung beetles in July 2011 (dry season) and January 2012 (rainy season) in eight areas: four pastures with native grasses (e.g., Andropogon spp. and Axonopus spp.) and four pastures with introduced grasses (Urochloa spp.) in Aquidauana, Mato Grosso do Sul, Brazil. To collect the insects, we used pitfall traps baited with carrion, cattle dung and human feces. A total of 7,086 dung beetles of 32 species were captured. In both pasture types, only traps baited with human feces captured similar abundance, species richness, and functional diversity compared with the sum total of beetles captured by the three bait types. The species richness and functional diversity were higher in the rainy season in both pasture types. Our results demonstrate that using human feces alone as bait and sampling dung beetles in the rainy season are potentially sufficient to ensure the greatest number of functional traits, species, and individuals in both pasture types. Thus, the best sampling method observed in this study may be useful for studies focused on dung beetle fauna survey and rigorous comparison among studies on these insects in Brazilian pastures.

Assuntos

RESUMO

Abstract The distribution of most species occurs in delimited regions with unique characteristics called centers of endemism. In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70s. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.

Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como centros de endemismo. Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.

RESUMO

This study aimed to monitor the population fluctuation of Cophes notaticeps (Marshall) (Coleoptera: Curculionidae) in a jatropha (Jatropha curcas L.) plantation in the Federal District, Brazil, through the use of a new trap, combined with different attractive lures and trap colors. The study was conducted at Embrapa Cerrados (Planaltina/DF) in a field trial with 720 plants. The new trap, named CPAC16, was made with PVC pipes (100 mm in diameter) of about 40 cm in length, with a window (8 × 10 cm2) in its center to enable insect access. A lure compartment was fixed on the inside of the trap`s top, and a pot, containing water and detergent, was placed at its bottom to collect the insects. The traps were painted in red, yellow, blue and green. Molasses, ethanol and pineapple were used as attractive lures. The traps were in the field trial area between May 2013 and April 2014 and the insects were collected weekly. The incidence of plants presenting damage caused by C. notaticeps was evaluated in the beginning and at the end of the study. The CPAC16 trap proved efficient in monitoring C. notaticeps. About 3494 of C. notaticeps adults were collected during the study. There were no significant differences among traps painted with different colors. The most attractive lure was molasses collecting 75.2% (n = 2627) of the specimens. Although the population peak occurred in December (n = 1162), C. notaticeps were collected throughout the year. The incidence of plants attacked by C. notaticeps ranged from 66.4% (start) to 100% (end).

Assuntos

RESUMO

Abstract The effect of catch-and-release fishing on the survival of peacock bass (Cichla spp.) was evaluated by comparing two types of artificial bait (jig and shallow-diver plugs) and two types of post-catch confinement. Two experiments were conducted during the periods January-February and October-November 2012 in the Unini River, a right-bank tributary of the Negro River. In total, 191 peacock bass were captured. Both groups of fish were subjected to experimental confinement (collective and individual) for three days. Additionally, 11 fish were tagged with radio transmitters for telemetry monitoring. Mortality rate was estimated as the percentage of dead individuals for each type of bait and confinement. For peacock bass caught with jig baits, mortality was zero. The corresponding figure for shallow-diver bait was 1.66% for fish in collective containment, 18.18% for fish monitored by telemetry and 0% for individuals confined individually. Our results show low post-release mortality rates for peacock bass. Furthermore, neither the type of confinement nor the type of bait had a statistically significant influence on mortality rates. While future studies could include other factors in the analysis, our results show that catch-and-release fishing results in low mortality rates.

Resumo O efeito do pesque-solte na sobrevivência do tucunaré (Cichla spp.) foi avaliado comparando dois tipos de iscas artificiais, jig e de meia-água, e dois tipos de confinamento pós-captura. Dois experimentos foram conduzidos durante os períodos de janeiro-fevereiro e outubro-novembro de 2012, no Rio Unini, afluente da margem direita do Rio Negro. No total, 191 tucunarés foram capturados. Os peixes foram submetidos a um confinamento experimental (coletivo e individual) com duração de três dias. Além disso, 11 peixes foram marcados com radiotransmissores e liberados imediatamente após a captura, sendo monitorados por telemetria. A taxa de mortalidade foi calculada como a porcentagem de indivíduos mortos para cada tipo de isca e tratamento (confinamento individual, coletivo e sem confinamento). Não houve mortalidade para o grupo de tucunarés capturados com isca jig. A isca de meia-água mostrou uma taxa de mortalidade de 1,66% para o confinamento coletivo e 18,18% para os peixes monitorados por telemetria. Nossos resultados mostraram baixas taxas de mortalidade pós-soltura para tucunaré. Além disso, nem o tipo de confinamento, nem o tipo de isca tiveram influência significativa nas taxas de mortalidade. Ainda que estudos futuros possam incluir novos fatores na análise, os nossos resultados mostram que a prática do pesque-solte resulta em baixas taxas de mortalidade.

RESUMO

Abstract The effect of catch-and-release fishing on the survival of peacock bass (Cichla spp.) was evaluated by comparing two types of artificial bait (jig and shallow-diver plugs) and two types of post-catch confinement. Two experiments were conducted during the periods January-February and October-November 2012 in the Unini River, a right-bank tributary of the Negro River. In total, 191 peacock bass were captured. Both groups of fish were subjected to experimental confinement (collective and individual) for three days. Additionally, 11 fish were tagged with radio transmitters for telemetry monitoring. Mortality rate was estimated as the percentage of dead individuals for each type of bait and confinement. For peacock bass caught with jig baits, mortality was zero. The corresponding figure for shallow-diver bait was 1.66% for fish in collective containment, 18.18% for fish monitored by telemetry and 0% for individuals confined individually. Our results show low post-release mortality rates for peacock bass. Furthermore, neither the type of confinement nor the type of bait had a statistically significant influence on mortality rates. While future studies could include other factors in the analysis, our results show that catch-and-release fishing results in low mortality rates.

Resumo O efeito do pesque-solte na sobrevivência do tucunaré (Cichla spp.) foi avaliado comparando dois tipos de iscas artificiais, jig e de meia-água, e dois tipos de confinamento pós-captura. Dois experimentos foram conduzidos durante os períodos de janeiro-fevereiro e outubro-novembro de 2012, no Rio Unini, afluente da margem direita do Rio Negro. No total, 191 tucunarés foram capturados. Os peixes foram submetidos a um confinamento experimental (coletivo e individual) com duração de três dias. Além disso, 11 peixes foram marcados com radiotransmissores e liberados imediatamente após a captura, sendo monitorados por telemetria. A taxa de mortalidade foi calculada como a porcentagem de indivíduos mortos para cada tipo de isca e tratamento (confinamento individual, coletivo e sem confinamento). Não houve mortalidade para o grupo de tucunarés capturados com isca jig. A isca de meia-água mostrou uma taxa de mortalidade de 1,66% para o confinamento coletivo e 18,18% para os peixes monitorados por telemetria. Nossos resultados mostraram baixas taxas de mortalidade pós-soltura para tucunaré. Além disso, nem o tipo de confinamento, nem o tipo de isca tiveram influência significativa nas taxas de mortalidade. Ainda que estudos futuros possam incluir novos fatores na análise, os nossos resultados mostram que a prática do pesque-solte resulta em baixas taxas de mortalidade.

RESUMO

Abstract The distribution of most species occurs in delimited regions with unique characteristics called centers of endemism. In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70s. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.

Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como centros de endemismo. Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.

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The Cuatro Ciénegas Basin (CCB) comprises several oligotrophic aquatic ecosystems limited by phosphorus. These aquatic systems are dominated by a high prokaryotic diversity, shaped by the stress of low nutrient supplies and interspecific competition. Although fungi constitute a diverse and important component of microbial diversity, the microfungal diversity in the CCB remains to be unveiled. With the aim to explore microfungal diversity and ecological patterns in this area, we present the first investigation analyzing cultivable taxa from sediment and water, as well as lignocellulolytic taxa obtained from incubated submerged plant debris, and wood panels in three contrasting freshwater systems in the CCB: Churince, Becerra and Pozas Rojas. We chose a culture-based approach to analyze sediment and water samples in order to obtain fungal cultures, providing opportunities for a posteriori studies, and the possibility of ex situ preservation of the diversity. We evaluated sequence data from the nuclear ribosomal internal transcribed spacer including the 5.8 rDNA region for 126 isolates, revealing 37 OTUs. These OTUs were phylogenetically affiliated to several genera in the fungal phyla: Zygomycota, Basidiomycota, and Ascomycota. We recorded two OTUs with saline affinity, agreeing with previous findings on the prokaryotic communities with ancestral marine resemblances. All the studied systems showed moderate diversity levels, however discrepancies among the diversity indexes were observed, due to the occurrence of abundant taxa in the samples. Our results indicated that lignocellulolytic microfungal communities are dominated by transient fungal taxa, as resident species were not recorded perhaps as a result of the long-term strong competition with the highly adapted prokaryotic community. Moreover, the obtained microfungal taxa occurred mostly on the resident plant debris, rather than submerged wood panels, perhaps as a result of the high adaptation to specific environmental conditions. In conclusion, the CCB possess a moderate taxonomical diversity compared to other arid environments, probably as a result of high selective pressures. Nonetheless, due to high spatial and temporal heterogeneity, the functional fungal diversity was considerable as predicted by the intermediate disturbance hypothesis. Decisively, the assessment of microfungal diversity freshwater systems is relevant, since this ecological group of microorganisms represents an important indicator of trophic complexity and biotic interactions among microbial communities, having important implications for understanding eukaryotic survival at the oligotrophic limit for life.

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Linepithema micans (Forel) is considered to be the main ant species responsible for the spread of Eurhizococcus brasiliensis (Wille), a soil scale that damages vine plants in southern Brazil. In this work, the seasonal life cycle of L. micans was evaluated in vineyards to define the most appropriate time for the application of toxic baits for control. Ant nests were transported to the laboratory in plastic bags, and individual ants were separated into groups of eggs, larvae, pupae, workers, males, and queens, recording the number of individuals per colony. The seasonal life cycle of L. micans in the vineyards began in spring with the deposition of eggs by queens. During the warm months of the year (spring and summer), it was possible to observe nests consisting primarily of eggs and pupae. During the autumn and winter months, the colonies were composed predominantly of larvae and a reduction in eggs was observed. Because the main control strategy targets the larval stage of the insect, the application of toxic baits for the control of L. micans must be performed during the winter.

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This paper presents information about the species richness and abundance of orchid bees in the transitional area between the Cerrado and the Amazon Forest in the Xingu river basin. The males were collected in a forest fragment in the municipality of Ribeirão Cascalheira, northeast Mato Grosso state, Brazil, between 1 and 5 November 2011. Benzyl benzoate, 1.8 cineole, eugenol and vanillin were used as baits, to attract the bees using insect nets and methyl salicylate was used only in the bottle traps. A total of 168 males belonged to four of five Euglossini genera distributed among 16 species were recorded. The greatest species richness was registered in the genus Euglossa, however Eulaema nigrita, was the most abundant Euglossine species in the community. The species richness varied between the edge and the first point within the fragment. The males were more active between 10:00 and 11:00 h, and the 1.8 cineole was the most attractive substance. The fragment studied contained representative species richness of orchid bees in a region of widespread environmental heterogeneity, which is still largely unknown as regards its pollinators and deserves attention for the compilation of new inventories.

En este trabajo se presenta información sobre la riqueza de especies y abundancia de Euglossini en la zona de transición entre el Cerrado y la selva amazónica, en la cuenca del río Xingu. Las muestras se recogieron en un fragmento de bosque en el municipio de Ribeirão Cascalheira, nordeste de Mato Grosso, Brasil, entre el 1 y 5 de noviembre de 2011. Las sustancias puras de benzoato de bencilo, 1,8 cineol, eugenol y la vainillina fueron utilizadas como cebos para atraer los machos usando red de insectos aunque el salicilato de metilo se utilizó en trampas pasivas. Un total de 168 machos pertenecientes a cuatro géneros fueron registrados, distribuidos en 16 especies. La mayor riqueza de especies se registró en el género Euglossa, aunque Eulaema nigrita fue la especie más abundante en la comunidad. La riqueza de especies varió entre el borde y el primer punto dentro del fragmento. Los machos de abejas de orquídeas eran más activos entre 10:00-11:00 h, y el 1,8 cineol fue la sustancia pura más atractiva. El fragmento estudiado contenía un alto grado de riqueza de especies de abejas de orquídeas en una región de heterogeneidad ambiental extensa, que sigue siendo en gran parte desconocido con relación a su fauna de insectos polinizadores y merece la atención para la elaboración de nuevos inventarios.

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Polyculture systems can promote greater economic efficiency with decreased use of inputs, making the activity more sustainable. The aim of this study was to evaluate the economic feasibility to grow-out lambari (Deuterodon iguape) in cages installed in Nile tilapia (Oreochromis niloticus) ponds. We calculated operational costs and determined the Internal Rate of Return (IRR), Net Present Value (NPV) and the Pay Back Period (PBP) to assess the economic viability of the investment. In a ten-year horizon, the largest positive NPV obtained was $ 83,082.55 for the sale price of $ 0.09 unit-1 of lambari and $ 2.11 kg-1 of Nile tilapia. Under these conditions, the IRR was 61% and PBP was 1.58 years, considered a low risk result due to the speed of the return on invested capital. A simulation of increase the prices of commercial diets shows that the polyculture system can be economic unfeasible if the farmer cannot access the market of live baits for lambari. The polyculture system is economic feasible, even assuming an annual loss of production, considering selling lambari as live baits.

Sistemas de policultivo podem promover maior eficiência econômica com redução do uso de insumos, tornando a atividade mais sustentável. O objetivo deste estudo foi avaliar a viabilidade econômica para criação de lambari (Deuterodon iguape) em tanques-rede instalados em viveiros de tilápia-do-nilo (Oreochromis niloticus). Foi calculado o custo operacional e determinada a Taxa Interna de Retorno (TIR), o Valor Presente Líquido (VPL) e o Período de Retorno do Capital Investido (PRC) para avaliar a viabilidade econômica do investimento. Em um horizonte de dez anos, o maior VPL positivo obtido foi de US$ 83.082,55 para o preço de venda de US$ 0,09 unidade-1 de lambari e US$ 2,11 kg-1 de tilápia-do-nilo. Sob essas condições, a TIR foi de 61% e o PRC foi de 1,58 anos, considerado um resultado de baixo risco devido à velocidade do retorno sobre o capital investido. O sistema de policultivo é economicamente viável, mesmo assumindo uma perda anual de produção, considerando a comercialização de lambaris como iscas vivas.

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