Temporal abundance of Aedes aegypti in Manaus, Brazil, measured by two trap types for adult mosquitoes

A longitudinal study was conducted in Manaus, Brazil, to monitor changes of adult Aedes aegypti (L.) abundance. The objectives were to compare mosquito collections of two trap types, to characterise temporal changes of the mosquito population, to investigate the influence of meteorological variables on mosquito collections and to analyse the association between mosquito collections and dengue incidence. Mosquito monitoring was performed fortnightly using MosquiTRAPs (MQT) and BG-Sentinel (BGS) traps between December 2008-June 2010. The two traps revealed opposing temporal infestation patterns, with highest mosquito collections of MQTs during the dry season and highest collections of BGS during the rainy seasons. Several meteorological variables were significant predictors of mosquito collections in the BGS. The best predictor was the relative humidity, lagged two weeks (in a positive relationship). For MQT, only the number of rainy days in the previous week was significant (in a negative relationship). The correlation between monthly dengue incidence and mosquito abundance in BGS and MQT was moderately positive and negative, respectively. Catches of BGS traps reflected better the dynamic of dengue incidence. The findings help to understand the effects of meteorological variables on mosquito infestation indices of two different traps for adult dengue vectors in Manaus.

Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia

The Aedes aegypti vector for dengue virus (DENV) has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50%) and DENV-1 (35%). Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.

Apreçamento de opções sobre taxa de câmbio R$/US$ negociadas no Brasil: uma comparação entre os modelos Black e redes neurais artificiais

No estudo aqui apresentado, aplicou-se um modelo de rede neural multicamadas para o apreçamento de calls sobre taxa de câmbio R$/US$, negociadas na Bolsa de Valores, Mercadorias & Futuros de São Paulo (BM&FBovespa), para o período de janeiro de 2004 a dezembro de 2007. A partir dos preços efetivamente praticados no mercado, comparou-se o desempenho entre essa técnica e o modelo de Black, utilizando-se métricas usuais de erro e testes estatísticos. Os resultados obtidos revelaram, em geral, a melhor adequação do modelo de inteligência artificial, em comparação ao modelo de Black, nos diferentes graus de moneyness.

Use of medicinal plants by black women: ethnography study in a low-income community

Objective To explore beliefs, values and practices related to the use of medicinal plants among low-income black families. Method The research method was ethnography and the participant observation process was done in a low-income community in the peripheral area of the City of São Paulo. Twenty black women were interviewed. Results Two cultural sub-themes, I do use medicines that I learned to make with my mother and with religious practitioners to care for diseases and Home medicines are to treat problems that are not serious, and the cultural theme I do use home medicines to treat simple diseases because I always have them at my disposal, they are free and I don’t need a medical prescription represent beliefs, values, and practices related to the use of medicinal plants among low-income black families. Conclusion The development of such practices, which can hide ethnic and social vulnerability, reveals the resilience of low-income black women in the process of confronting problems during the health-illness process.

Larval endoparasitoids (Hymenoptera) of frugivorous flies (Diptera, Tephritoidea) reared from fruits of the cerrado of the State of Mato Grosso do Sul , Brazil

This paper presents a five years survey of endoparasitoids obtained from the larvae of frugivorous Tephritidae and Lonchaeidae flies. The insects were reared from cultivated and wild fruits collected in areas of the cerrado in the State of Mato Grosso do Sul, Brazil. The flies obtained from 14 host fruit species were eight Anastrepha species, Ceratitis capitata (Wiedemann, 1824) (Tephritidae); Dasiops sp. and Neosilba spp. (Lonchaeidae). Eleven parasitoid species were collected: Braconidae - Asobara anastrephae (Muesebek, 1958), Doryctobracon areolatus (Szépligeti, 1911), D. fluminensis (Costa Lima, 1938), Opius bellus Gahan, 1930 and Utetes anastrephae (Viereck, 1913); Figitidae - Aganaspis nordlanderi Wharton, 1998, Lopheucoila anastrephae (Rhower, 1919), Odontosema anastrephae (Borgmeier, 1935) and Trybliographa infuscata Gallardo, Díaz & Uchôa-Fernandes, 2000 and, Pteromalidae - Spalangia gemina Boucek, 1963 and S. endius Walker, 1839. In all cases only one parasitoid emerged per puparium. D. areolatus was the most abundant and frequent parasitoid of fruit fly species, as was L. anastrephae in Neosilba spp. larvae. This is the first record of A. nordlanderi in the midwestern Brazilian region.

Desenvolvimento de Ophyra albuquerquei Lopes (Diptera, Muscidae) em condições de laboratório

Ophyra albuquerquei may often be a potential predator of Musca domestica Linnaeus, 1758 in poultry and pig houses in southern Brazil. Here we address the developmental period of immatures stages and their viability. To obtain eggs, larvae and pupae, a colony was established in the laboratory. Adult flies were fed on a diet comprising two parts dry milk, two parts sugar and one part fish flour. Larval diet comprised one part fish flour and one part sawdust and water. The eggs, larvae and pupae were incubated at 26º ± 1ºC, 75% ± 10% R.H. and 12 h photoperiod. The egg to adult cycle took 573 h with a total viability of 64%. The shortest of the stages was the egg stage, which lasted about 20 h. The larval stage had the lowest viability (about 82%) and longest time interval (279 h). Overall, the results of this study show that O. albuquerquei can be readily maintained in the laboratory.

Influence of male nutritional conditions on the performance and alimentary selection of wild females of Anastrepha obliqua (Macquart)(Diptera, Tephritidae)

Influence of male nutritional conditions on the performance and alimentary selection of wild females of Anastrepha obliqua (Macquart) (Diptera, Tephritidae). The behavior of A. obliqua females is regulated by endogenous and exogenous factors and among these the presence of males. Experiments were carried out to investigate whether the presence of males and their nutritional condition may affect the behavior of self-selection feeding and the performance of A. obliqua females. Females were sorted in groups containing yeast-deprived females and males, and non-yeast-deprived females and males. The females were maintained apart from the males by a transparent plastic screen. Several yeast and sucrose combinations were offered to the females in a single diet block or in separate blocks. Ingestion, egg production, longevity and diet efficiency were determined. The non-yeast-deprived males positively influenced the females performance when the latter were fed with yeast and sucrose in distinct diet blocks. Performance was better in the groups without males and with yeast-deprived males where the females could not select the nutrient proportions (yeast and sucrose in a single diet block).

Floral biology of Stachytarpheta maximiliani Scham. (Verbenaceae) and its floral visitors

This study describes the reproductive system of Stachytarpheta maximiliani (Verbenaceae), including its floral biology, nectar and pollen availability and insect foraging patterns, identifying whose species act as pollinators. It was carried out in a Brazilian Atlantic rain forest site. Observations on the pollination biology of the Verbenaceae S. maximiliani indicate that their flowering period extends from September through May. Anthesis occurs from 5:30 a.m. to 5:00 p.m. and nectar and pollen are available during all the anthesis. Many species of beetles, hemipterans, flies, wasps, bees and butterflies visit their flowers, but bees and butterflies are the most frequent visitors. The flowers are generally small, gathered in dense showy inflorescences. A complex of floral characteristcs, such as violet-blue color of flowers, long floral tubes, without scents, nectar not exposed, high concentration of sugar in nectar (about 32%), allowed identification of floral syndromes (melittophily and psicophily) and function for each visitor. The bees, Bombus morio, B. atratus, Trigonopedia ferruginea, Xylocopa brasilianorum and Apis mellifera and the butterflies Corticea mendica mendica, Corticea sp., Vehilius clavicula, Urbanus simplicius, U. teleus and Heraclides thoas brasiliensis, are the most important pollinators.

Foraging by Polybia (Trichothorax) ignobilis (Hymenoptera, Vespidae) on flies at animal carcasses

Proteins for brood nutrition of social wasps are obtained from many prey, including insects (even bees and other wasps), spiders and bits of decaying meat. After being captured and killed, prey are reduced to a shapeless mass and distributed to the brood. Little is known about the foraging activity, especially on this group. Herein we describe the sequence of foraging behaviours of the social wasp Polybia (Trichothorax) ignobilis for hunting flies (Diptera: Calliphoridae and Muscidae) over pig carcasses. To our knowledge, there are few scientific descriptions of prey foraging behaviour on this species.

Key to the adults of the most common forensic species of Diptera in South America

Flies (Diptera, blow flies, house flies, flesh flies, horse flies, cattle flies, deer flies, midges and mosquitoes) are among the four megadiverse insect orders. Several species quickly colonize human cadavers and are potentially useful in forensic studies. One of the major problems with carrion fly identification is the lack of taxonomists or available keys that can identify even the most common species sometimes resulting in erroneous identification. Here we present a key to the adults of 12 families of Diptera whose species are found on carrion, including human corpses. Also, a summary for the most common families of forensic importance in South America, along with a key to the most common species of Calliphoridae, Muscidae, and Fanniidae and to the genera of Sarcophagidae are provided. Drawings of the most important characters for identification are also included.

Selection of artificial hosts for oviposition by wild Anastrepha obliqua (Macquart) (Diptera, Tephritidae): influence of adult food and effect of experience

Several factors influence the selection of oviposition substrates by insects. The aim of the present work was to find answers to the following questions related to the oviposition behavior of Anastrepha obliqua. Can carbohydrates (glucose or sucrose) present in the adult diet have influence on the female preference for an oviposition substrate with similar composition? Can the previous experience with a host containing one of mentioned carbohydrates interfere in further selection of oviposition substrates? The results showed that the kind of carbohydrate present in the adult diet did not affect the female preference for an artificial oviposition substrate, neither when it was presented by itself nor in combination with brewer's yeast. The effect of experience in the oviposition behavior was observed when there was a previous contact with artificial oviposition substrates containing yeast and sucrose. The data are discussed in terms of the behavioral plasticity presented by this species in relation to feeding and oviposition behaviors.

Review of semiochemicals that mediate the oviposition of mosquitoes: a possible sustainable tool for the control and monitoring of Culicidae

The choice for suitable places for female mosquitoes to lay eggs is a key-factor for the survival of immature stages (eggs and larvae). This knowledge stands out in importance concerning the control of disease vectors. The selection of a place for oviposition requires a set of chemical, visual, olfactory and tactile cues that interact with the female before laying eggs, helping the localization of adequate sites for oviposition. The present paper presents a bibliographic revision on the main aspects of semiochemicals in regard to mosquitoes' oviposition, aiding the comprehension of their mechanisms and estimation of their potential as a tool for the monitoring and control of the Culicidae.

Bat flies (Diptera, Streblidae and Nycteribiidae) in a Cerrado area of Goiás State, Brazil

A survey of bat flies was carried out in the Brazilian savanna (Cerrado) in the Goiás state, Brazil. We collected 227 specimens of seventeen species belonging to nine genera of Streblidae and seven specimens of four species of Basilia Miranda-Ribeiro, 1903 (Nycteribiidae). Except for Paratrichobius longicrus (Miranda-Ribeiro, 1907) (Streblidae), all species are new recorded in Goiás.

Mosquitoes (Diptera, Culicidae) inhabiting foliar tanks of Guzmania brasiliensis Ule (Bromeliaceae) in central Amazonia, Brazil

Mosquitoes in the family Culicidae develop their immature forms in different environments depending on various circumstances. This study represents the first contribution to the ecological knowledge of culicids living in the bromeliad G. brasiliensis. The objectives of the study were to compare the Culicidae fauna of bromeliads in two seasonal periods, analyzing their abundance, richness and the influence of pH, conductivity and water volume, on the populations. Sampling was done at Reserva Adolpho Ducke, Manaus, Amazonas, Brazil between 2003 and 2005. Six samplings were done in the rainy season and six in the dry season. On each sampling day, six terrestrial and six epiphytic bromeliads, totaling 144 sampling units, were retrieved. A total of 444 immature mosquitoes were collected, distributed in the following species: Culex (Microculex) stonei Lane & Whitman, Culex (Microculex) chryselatus Dyar & Knab, Culex (Microculex) sp., Wyeomyia (Hystatomyia) autocratica Dyar & Knab and Wyeomyia (Hystatomyia) splendida Bonne-Wepster & Bonne. The relationship between abundance of Culicidae and sampling period was not significant, although abundance was higher in the dry period. There were significant correlations between water volume and the abundance (p = 0.003) and richness (p = 0.001) of culicids. The pH was positively related to the occurrence of the species Wy. autocratica (p= 0.010) and Wy. splendida (p= 0.006), demonstrating the influence of this factor in the structuring of bromeliad-inhabiting communities.

Nyssomyia intermedia (Lutz & Neiva) and Nyssomyia neivai (Pinto) (Diptera, Psychodidae, Phlebotominae) in a sympatric area: seasonal and nocturnal hourly rhythm in black and white modified Shannon traps

Captures with black and white Shannon traps were undertaken to identify aspects of the behavior of the two cryptic and sympatric species implicated as vectors of cutaneous leishmaniasis, Nyssomyia intermedia (Lutz & Neiva, 1912) and Nyssomyia neivai (Pinto, 1926). The traps were installed side by side, monthly, from July 2001 to June 2002, from 18 to 07 hours, in a peridomicile of Iporanga municipality, state of São Paulo, Brazil. A total of 2,142 specimens were captured, Ny. intermedia (47.4%) and Ny. neivai (50.5%). The white trap was more attractive to both sexes of both species. Males of Ny. neivai predominated (70%) over those of Ny. intermedia on the two traps; on the black trap, the females of Ny. intermedia predominated (63.3%) over those of Ny. neivai (36.7%). Seventy percent of the specimens of both species were captured between 18 and 24 h. Females of Ny. intermedia presented the highest peak at 19-20 h, and those of Ny. neivai at 20-21 h. The highest hourly average for females of Ny. intermedia on the black trap occurred in the winter and that for males in the summer. For Ny. neivai, both sexes predominated in the summer. The two species probably transmit the cutaneous leishmaniasis in the area due to their great predominance.