Diversity of Mosquitoes (Diptera: Culicidae) in the Caatinga Biome, Brazil, from the Widespread to the Endemic.

Mosquito fauna in the northeast semiarid region of Brazil, Caatinga biome, are poorly known. Studies on the diversity are scarce and the few surveys available focus on local fauna. In order to understand the ecological pattern of mosquito's distribution, information available from studies from 2008 to 2015 were gathered. A partitioning framework of the beta diversity, the turnover (ßJTU) and nestedness (ßJNE) components were used to determine dissimilarity among communities. Eighty-two morphospecies were recorded and 47 of the species were not shared between the areas. The most representative genera were Aedes, Anopheles, Psorophora, Haemagogus, Coquillettidia, and Mansonia, which all include species of medical interest. The communities had high rates of variation, and the mechanism of turnover accounted for the observed diversity pattern. Despite differences in collection methods, the observed dissimilarity may be related to the broad environmental heterogeneity of the biome, the intrinsic relationships of the species with their habitats, and the environmental degradation caused by different types of anthropogenic interference. Considering the mosquito species richness and endemicity, the hypothesis that the Caatinga harbor poor biodiversity is rejected. The spatial variation observed is of particular importance and should be taken into account for the knowledge of Caatinga biodiversity.

Mosquitoes of the Caatinga. III. Larval Habitats, Frequency, and Dynamics of Immature and Adult Stages in a Dry Brazilian Forest.

Even though the seasonally dry tropical Caatinga forest is an historically neglected biome, recent studies have enhanced our knowledge of its biodiversity. We investigated larval habitats as well as the frequency and dynamics of immature and adult Culicidae in a conservation unit within the Caatinga in the Brazilian state of Sergipe. We carried out monthly surveys between July 2011 and October 2012 to count both immature (tree holes, bromeliad tanks, ponds, and rock holes and depressions) and adult individuals (Shannon traps baited with light). In total 8,021 individuals representing 32 taxa, eight of which are currently undescribed, were collected. The majority of the specimens collected came from tree holes followed by bromeliads, ponds, and rock depressions. Ponds had the highest species richness in this survey while the bromeliad fauna exhibited high endemicity. We also reveal a correlation between precipitation during the month prior to collection and the abundance of immature individuals in tree holes. Peaks in Haemagogus sp. near spegazzinii and Aedes terrens abundance were observed soon after rain, whereas Culex conservator was abundant during the rainy season in tree holes evidencing a species rotation within this habitat. Although the results of this study contribute to our knowledge regarding the distribution of mosquitoes in Brazilian semiarid region, further taxonomic studies will be required to fully understand the richness and endemism of the Neotropical Culicidae fauna.

Variation in temephos resistance in field populations of Aedes aegypti (Diptera: Culicidae) in the State of Sergipe, Northeast Brazil.

INTRODUCTION: The organophosphate temephos was first used in Brazil in the 1960s for the control of Aedes aegypti. Because of its extensive and longstanding use worldwide, selection for mosquito populations resistant to the chemical has been observed not only in different regions of Brazil but also in several parts of the world. The objective of this study was to evaluate the susceptibility of Ae. aegypti to the organophosphate temephos, a larvicide used in vector control activities in Sergipe/Northeast Brazil. METHODS: This study included mosquito populations from seven municipalities of Sergipe and was carried out from October 2010 to August 2011. Qualitative bioassays of diagnostic dose and dose responses were performed. The resistance ratio was calculated based on lethal concentrations for mosquitoes of the susceptible Rockefeller strain. RESULTS: All populations were classified as resistant to temephos. The resistance ratio ranged from 22.2 to 297.9, the lowest being seen in Aracaju, a coastal area of the state, and the highest in Pinhão, a semi-arid region, 96.6km from Aracaju. CONCLUSIONS: High levels of temephos resistance were observed in the Ae. aegypti populations of Sergipe. The variation between regions indicates that there have been different regimes of insecticide use and also points to the potential of small cities to generate and spread insecticide resistance.

Variation in temephos resistance in field populations of Aedes aegypti (Diptera: Culicidae) in the State of Sergipe, Northeast Brazil

Abstract INTRODUCTION The organophosphate temephos was first used in Brazil in the 1960s for the control of Aedes aegypti. Because of its extensive and longstanding use worldwide, selection for mosquito populations resistant to the chemical has been observed not only in different regions of Brazil but also in several parts of the world. The objective of this study was to evaluate the susceptibility of Ae. aegypti to the organophosphate temephos, a larvicide used in vector control activities in Sergipe/Northeast Brazil. METHODS This study included mosquito populations from seven municipalities of Sergipe and was carried out from October 2010 to August 2011. Qualitative bioassays of diagnostic dose and dose responses were performed. The resistance ratio was calculated based on lethal concentrations for mosquitoes of the susceptible Rockefeller strain. RESULTS: All populations were classified as resistant to temephos. The resistance ratio ranged from 22.2 to 297.9, the lowest being seen in Aracaju, a coastal area of the state, and the highest in Pinhão, a semi-arid region, 96.6km from Aracaju. CONCLUSIONS: High levels of temephos resistance were observed in the Ae. aegypti populations of Sergipe. The variation between regions indicates that there have been different regimes of insecticide use and also points to the potential of small cities to generate and spread insecticide resistance.

Mosquitoes of the Caatinga: 2. Species from periodic sampling of bromeliads and tree holes in a dry Brazilian forest.

The Caatinga is a dry tropical forest, located in the Brazilian semiarid region and rich in phytotelmata. This study investigated the culicid fauna of phytotelmata of the caatinga by sampling for 19 consecutive months aquatic immatures from tree holes and bromeliads. A total of 127L of water was taken from the plants, containing 6764 immature culicids of 16 species, of which 11 (69%) are undescribed and respond to 90% of the total abundance of the specimens collected. Epiphytic bromeliads harbor a large number of immature Culicidae, although terrestrial bromeliads are the most abundant and widely distributed in the region. The richness of culicid species was similar between terrestrial and epiphytic bromeliads and lower in habitats represented by tree hole phytotelmata. There was no similarity in the composition of culicid species that developed in bromeliads or tree holes. Temperature and humidity were the environmental parameters most strongly associated with the proportion of positive plants. The Caatinga has a great number of endemic species that remain unknown to science and many additional culicid species may await discovery from there.

Mosquitoes of the Caatinga: 1. Adults stage survey and the emerge of seven news species endemic of a dry tropical forest in Brazil.

The Caatinga is the least known Brazilian biome in terms of the diversity of Culicidae. No systematic study of the diversity or ecology of the mosquitoes of this biome is available, despite the importance of vector diseases in Brazil. The present study addressed the mosquito biodiversity in the Caatinga biome by sampling adult populations. Specimens were sampled monthly from March 2013 to September 2014 in a Caatinga conservation unit located in the Brazilian semiarid zone. Mosquito collections were carried out in Shannon traps from late afternoon to early evening, and manual aspiration was used to capture diurnal species as well. A total of 4,692 mosquitoes were collected. The most dominant and constant species were all undescribed species belonging to the genera Wyeomyia and Runchomyia, which together represented 80% of the specimens. The most abundant species of epidemiological importance was Haemagogus (Con.) leucocelaenus. The abundance of mosquitoes was positively associated with the relative humidity and temperature recorded during the month preceding the collection date. In the Caatinga, the diversity of adult mosquitoes was associated with the availability (quantity and diversity) of natural larval habitats found in the different phytophysiognomies of the biome, which vary according to temperature and humidity. The number of species unknown to science reflects the levels of endemism that exist in the study area, and reinforces the need to further taxonomic investigation in the biome.

Mosquitos da Caatinga: biodiversidade, aspectos ecológicos e importância epidemiológica da fauna Culicidae do semiárido brasileiro / Mosquitoes of the Caatinga biodiversity, ecology and epidemiological importance of Culicidae fauna of the Brazilian semiarid

Em relação à fauna Culicidae, a Caatinga é um dos biomas mais desconhecidos do Brasil. Há carência de registro de ocorrência de culicídeos, bem como de estudos sobre as interações deles com o ambiente silvestre. Assim, o objetivo deste estudo foi investigar biodiversidade e aspectos ecológicos e epidemiológicos da fauna Culicidae em áreas de conservação do bioma Caatinga. Para isso foram consideradas duas unidades de conservação da Caatinga e realizados 19 levantamentos entomológicos mensais e consecutivos. Foram realizadas coletas de formas imaturas de mosquitos em bromélias, ocos de árvore e criadouros de solo, além da coleta de mosquitos adultos de hábitos diurno, crepuscular e noturno. Ao todo, entre mosquitos adultos e imaturos associados a habitats fitotelmatas, foram coletados 11.456 culicídeos distribuídos em 28 espécies, das quais 11 eram desconhecidas para a ciência. A fauna de imaturos coletados em bromélias e ocos de árvore interferiu na composição da fauna de mosquitos adultos e houve variações na abundância e nos padrões de diversidade de acordo com fitofisionomia do ambiente. Temperatura e umidade foram os parâmetros ambientais mais fortemente associados à abundância de culicídeos. Foram registradas novas ocorrências de anofelinos, coletados em criadouros de solo, ampliando a distribuição das espécies para o semiárido brasileiro

Regarding Culicidae fauna, Caatinga is one of the most unknown biomes of Brazil. There are few records of mosquitoes occurrence, as well as studies on their interactions with the wild environment. Therefore, the aimof this study was to investigate the biodiversity, ecological and epidemiological aspects of Culicidae fauna in conservation areas of the Caatinga biome. Two protected areas were considered for the study and 19 entomological surveys were performed monthly. Immature forms of mosquitoes were collected in bromeliads, tree holes and ground pools, as well as collection of adult mosquitoes with day time, twilight and nocturnal habits. Between adults and immatures associated with phytotelmatas habits, a total of 11,456 mosquitoes were collected, distributed in 28 species, 11 of which were unknown to science. The immature fauna collected in bromeliads and tree holes interfered in the fauna composition of adults and there were variations in the abundance and diversity patterns according to the environment phytophysiognomy. Temperature and humidity were the most strongly environmental factors associated with the abundance of mosquitoes. New records of anophelines collected inground pools were registered, broadening the distribution of species in the Brazilian semiarid region

[Identification and spatial distribution of key premises for Aedes aegypti in the Porto Dantas neighborhood, Aracaju, Sergipe State, Brazil, 2007-2008]. / Identificação e distribuição espacial de imóveis-chave de Aedes aegypti no bairro Porto Dantas, Aracaju, Sergipe, Brasil entre 2007 e 2008.

Currently the best way to avoid new dengue epidemics is to control the mosquito vector Aedes aegypti. This study thus aimed to identify and analyze the spatial distribution of "key premises" for Ae. aegypti in Aracaju, Sergipe State, Brazil. Three entomological surveys were performed prior to, during, and after the dengue epidemic and in different conditions of precipitation: the end of the rainy season, beginning of the rainy season, and the dry season. Key premises were identified by positivity in more than one survey and presence of pupae. Spatial distribution and dispersal of mosquitoes used analysis of point patterns, with the kernel and buffer density estimator. Key premises were responsible for maintaining infestation of the area, independently of environmental conditions and the period in the epidemic, serving as foci generating mosquitoes that can spread to areas adjacent to the neighborhood. Thus, in order to be more effective, vector control measures should target these properties.

Identificação e distribuição espacial de imóveis-chave de Aedes aegypti no bairro Porto Dantas, Aracaju, Sergipe, Brasil entre 2007 e 2008 / Identification and spatial distribution of key premises for Aedes aegypti in the Porto Dantas neighborhood, Aracaju, Sergipe State, Brazil, 2007-2008 / Identificación y distribución espacial de recipientes-clave de Aedes aegypti en el barrio Porto Dantas, Aracaju, Sergipe, Brasil entre 2007 y 2008

A melhor forma de evitar novas epidemias de dengue é controlar o vetor, o mosquito Aedes aegypti. Assim, este estudo objetivou identificar e analisar a distribuição espacial dos imóveis-chave para Ae. aegypti em Aracaju, Sergipe, Brasil. Para isso, três levantamentos entomológicos foram realizados em períodos antes, durante e após a epidemia de dengue e em diferentes condições de precipitação: fim do período chuvoso, início da estação chuvosa e estiagem. Para identificar os imóveis-chave, foram consideradas as variáveis: positividade em mais de um levantamento e presença de pupas; e para verificar a distribuição espacial e dispersão dos mosquitos, foi realizada análise de padrões pontuais, por meio do estimador de densidade de kernel e buffer. Constatou-se que os imóveis-chave são responsáveis pela manutenção da infestação na localidade independente das condições ambientais e do período epidêmico e são focos geradores de mosquitos que podem se dispersar para áreas vizinhas ao bairro. Dessa forma, as ações de controle vetorial, para serem mais efetivas, devem ser direcionadas para esses imóveis.

Currently the best way to avoid new dengue epidemics is to control the mosquito vector Aedes aegypti. This study thus aimed to identify and analyze the spatial distribution of "key premises" for Ae. aegypti in Aracaju, Sergipe State, Brazil. Three entomological surveys were performed prior to, during, and after the dengue epidemic and in different conditions of precipitation: the end of the rainy season, beginning of the rainy season, and the dry season. Key premises were identified by positivity in more than one survey and presence of pupae. Spatial distribution and dispersal of mosquitoes used analysis of point patterns, with the kernel and buffer density estimator. Key premises were responsible for maintaining infestation of the area, independently of environmental conditions and the period in the epidemic, serving as foci generating mosquitoes that can spread to areas adjacent to the neighborhood. Thus, in order to be more effective, vector control measures should target these properties.

La mejor forma de evitar nuevas epidemias de dengue es controlar el vector, el mosquito Aedes aegypti. Por ello, este estudio tuvo por objetivo identificar y analizar la distribución espacial de los recipientes-clave para Ae. aegypti en Aracaju, Sergipe, Brasil. Con este fin, tres estudios entomológicos se realizaron en períodos anteriores, durante y después de la epidemia de dengue y en diferentes condiciones de precipitación pluvial: fin del período lluvioso, inicio de la estación de lluvias y período seco. Para identificar los recipientes-clave, se consideraron las variables: positividad en más de un estudio y presencia de crisálidas; y para verificar la distribución espacial y la dispersión de los mosquitos, se realizó un análisis de padrones puntuales, por medio del estimador de densidad de kernel y buffer. Se constató que los recipientes-clave son responsables del mantenimiento de la infestación en la localidad, independientemente de las condiciones ambientales y del período epidémico, además, son focos generadores de mosquitos que pueden dispersarse hacia áreas vecinas del barrio. De esta forma, las acciones de control vectorial, para ser más efectivas, deben estar dirigidas hacia esos inmuebles.

Risk of dengue occurrence based on the capture of gravid Aedes aegypti females using MosquiTRAP.

We assessed the risk classification of dengue fever based on the capture of Aedes aegypti adults using MosquiTRAP, a type of sticky trap, in comparison with traditional larval infestation indices. A total of 27 MosquiTRAPs were installed, with one trap per block, and were inspected weekly between November 2008-February 2009. Infestation baseline data were obtained from a survey conducted prior to trap installation. The index generated by MosquiTRAP and house index (HI) classified the area "in alert situation". The set for risk of dengue occurrence proposed by the use of MosquiTRAP classify areas in the same way of the traditional HI.

Risk of dengue occurrence based on the capture of gravid Aedes aegypti females using MosquiTRAP

We assessed the risk classification of dengue fever based on the capture of Aedes aegypti adults using MosquiTRAP, a type of sticky trap, in comparison with traditional larval infestation indices. A total of 27 MosquiTRAPs were installed, with one trap per block, and were inspected weekly between November 2008-February 2009. Infestation baseline data were obtained from a survey conducted prior to trap installation. The index generated by MosquiTRAP and house index (HI) classified the area "in alert situation". The set for risk of dengue occurrence proposed by the use of MosquiTRAP classify areas in the same way of the traditional HI.