Density and diversity of Culicidae (Diptera), with analysis of viral circulation, in urban public establishments in Northern Paraná, Brazil

ABSTRACT Brazil has been suffering a dengue (DENV) epidemic in 2019 and 2022 and records cases of Zika (ZIKV) and chikungunya (CHIKV). Londrina city, Paraná, stands out for the number of cases and deaths from dengue. Therefore, this study aimed to verify the density and diversity of mosquitoes present in urban public establishments of Londrina, to analyze their ecological relationships, and to investigate the presence of the DENV, ZIKV, and CHIKV. Ovitraps were installed in outdoor sites in two public establishments in each region of Londrina, while adult culicids were caught indoors with a Nasci aspirator. A total of 5077 eggs were obtained in 77 ovitraps. The South region had the highest infestation while the East had the lowest (Ovitrap Positivity Index: 38% and 25%; Egg Density Index: 67.83 and 19.03, respectively). From eggs, 704 Aedes aegypti females and 71 Aedes albopictus females were obtained, while in the aspiration of adults, 99 A. aegypti and 11 Culex quinquefasciatus were captured, the highest number in the West and the lowest in the North. The DENV-II virus was detected in a pool of 17 A. aegypti females in the West region. The results demonstrate high density of pathogen vector species, mainly A. aegypti, in and around establishments, alerting to the need for constant local entomological surveillance to prevent viral circulation, mainly in crowded places. The presence of A. albopictus around the establishments also alerts to the urbanization of the species and potential participation in the viral circulation, demonstrating the need for constant monitoring.

New occurrences of mosquitoes (Diptera: Culicidae) in the Atlantic Forest biome of the Brazilian Northeast

ABSTRACT Background: Information regarding the distribution of Culicidae species in the northeastern region of Brazil is scarce. Methods: Immatures were collected from approximately four fragments of the Atlantic Forest. Results: This study presents new occurrences of 18 Culicidae species in Pernambuco state: Anopheles kompi, Georgecraigius fluviatilis, Culex bidens, Culex chidesteri, Culex bastagarius, Culex imitator, Mansonia humeralis, Wyeomyia incaudata, Uranotaenia apicalis, Culex mollis, Culex usquatus, Culex dunni, Culex serratimarge, Culex ybarmis, Culex microphyllus, Sabethes purpureus, Wyeomyia pilicauda, and Wyeomyia airosai. The last nine species were also new records for the northeast region. Conclusions: With the inclusion of these newly recorded species, the total number of mosquitoes documented in Pernambuco state now rises to 94.

Genetic diversity and Kdr mutations of natural Aedes (Stegomyia) aegypti (Diptera: Culicidae) populations of Brazil

ABSTRACT Aedes (Stegomyia) aegypti is an important vector of dengue, yellow fever, chikungunya and Zika virus. It is well known that resistance monitoring and genetic diversity data help designing the vector control programs. This study aimed to evaluate resistance to pyrethroids (PYs) through the frequency of kdr mutations Val1016IIe and F1534C, and the genetic variation of the mitochondrial gene ND4 in six natural populations of A. aegypti from Paraná - Brazil. Adults were obtained from eggs collected from Alvorada do Sul, Marilena, Maringá, Nova Londrina, Paranavaí and São Carlos do Ivaí. From these adults, 345 were used to identify the 1016 and 1534 sites, and 120 were used to perform the ND4 gene analysis. The studied populations from Paraná showed PYs resistance, low gene flow and genetic diversity. Additionally, a relationship was observed among the haplotypes of populations from the Amazon and Southeastern Brazil, Peru, Mexico, and North America.

Gene Flow Patterns of the Aedes aegypti (Diptera: Culicidae) Mosquito in Colombia: a Continental Comparison Suggests Multiple Invasion Routes and Gene Exchange

ABSTRACT In Colombia Aedes aegypti is present in 80% of the country up to 2,300 m; however, little is known of its genetic relations within a country context and, hence, within a broader context, for example, America. The aforementioned, herein, analyzed the gene flow within a context of the Americas, its directionality and genetic diversity of the mitochondrial lineages in the A. aegypti populations for Colombia. This called for the use of the sequences for A. aegypti available of the mitochondrial ND4 gene in the GenBank for Colombia and the American continent. No presence was found of nuclear mitochondrial pseudogenes (NUMTs) for Colombia. It is estimated that in Colombia the gene flow of the A. aegypti populations is occurring from the southeast and northeast toward the center of the country. In comparison with the mitochondrial sequences for America, the vector's haplotypes in Colombia suggest connections between the populations of mosquitoes from the south with those from the north of the continent. The gene flow model at continental scale suggests bidirectional connections between the populations from the north of the continent with those from the south, while at South American scale it proposes the gene flow in all the directions with respect to the Colombian. The Colombian A. aegypti vector monitoring and control strategies must pay special attention to the vector's points of entry into Colombia related with Peru, Venezuela, Brazil, Mexico, and North America to avoid the entry of populations with characteristics like resistance to insecticides or vector competition.

Cell damage induced by polybrominated diphenyl ethers on Chironomus sancticaroli (Diptera: Chironomidae)

Abstract Histological effects of polybrominated diphenyl ethers (PBDEs) were observed in Chironomus sancticaroli larvae which underwent acute exposure. 2,2′,4-triBDE (BDE-17), 2,2′,4,4′-tetraBDE (BDE-47) and 2,2′,4,4′,5-pentaBDE (BDE-99) were evaluated at 0.5, 2.0 and 20 μg L-1. Cytoplasm vacuolisation of oenocytes was observed in the larvae exposed to BDE-17 and BDE-47. Cuénot cells were disrupted at the brush border as an effect of the three evaluated congeners highlighting BDE-47 at 2.0 μg L-1; 60% of larvae displayed this disruption. The midgut showed changes in the morphology of apex cells located next to the lumen of region I exposed to BDE-17 and BDE-47, while BDE-99 induced a narrowing of the lumen diameter. Significant cytoplasm vacuolisation of the larvae exposed to BDE-47 and BDE-99 was observed in region II of the midgut. Salivary glands showed acidophilic granules in the cytoplasm exposed to BDE-17 and BDE-47. The results showed that the tissues of C. sancticaroli were sensitive to flame retardants; these histopathologies can compromise the health and physiology of this organism, highlighting the concern with the presence of PBDEs in freshwater sediments.

How much is known about the genetic diversity of the Asian tiger mosquito? A systematic review / ¿Cuánto se conoce acerca de la diversidad genética del mosquito tigre? Una revisión sistemática

ABSTRACT Introduction: Aedes (Stegomyia) albopictus (Skuse, 1894) is a vector for dengue and chikungunya viruses in the field, along with around 24 additional arboviruses under laboratory conditions. Knowledge of the genetic diversity of insect vectors is critical for the effective control and elimination of vector-borne diseases. Objective: We determined the current scenario of the genetic diversity in natural populations of A. albopictus through a systematic review. Methodology: It was possible to establish the first reports and distribution of A. albopictus populations in the world, as well as its genetic diversity, population genetic structure and molecular markers used to determine its genetic diversity. Results: A. albopictus is distributed worldwide with genetically structured populations and low diversity; however, 89.5% of the genetic diversity known is based on the use of RFLP, allozymes, isozymes, and mtDNA molecular markers that exhibit significant problems according to the literature. After the results were obtained, a critical analysis was carried out and existing shortcomings were detected. Conclusion: The current knowledge of genetic diversity of A. albopictus is based on genetic markers that exhibit significant problems reported in the literature; therefore, vector control programs targeting A. albopictus populations, may be compromised.

RESUMEN Introducción: Aedes (Stegomyia) albopictus (Skuse, 1894) es un vector para los virus del dengue y chicunguña en la naturaleza, junto con cerca de 24 arbovirus en condiciones de laboratorio. El conocimiento de la diversidad genética de los insectos vectores es fundamental para el control eficaz y la eliminación de enfermedades transmitidas por estos. Objetivo: Aquí se determinó el escenario actual de la diversidad genética en poblaciones naturales de A. albopictus a través de una revisión sistemática. Metodología: Se pudieron establecer los primeros registros y distribución de las poblaciones de A. albopictus en el mundo, así como su diversidad genética, estructura genética poblacional y marcadores moleculares utilizados para determinar su diversidad genética. Resultados: A. albopictus se distribuye en todo el mundo con poblaciones genéticamente estructuradas y baja diversidad; Sin embargo, el 89,5% de la diversidad genética conocida se basa en el uso de RFLP, aloenzimas, isoenzimas y marcadores moleculares mitocondriales que presentan problemas significativos según la literatura. Una vez obtenidos los resultados, se realizó un análisis crítico y se detectaron deficiencias existentes. Conclusión: El conocimiento actual de la diversidad genética de A. albopictus se basa en marcadores genéticos que presentan problemas significativos reportados en la literatura; Por lo tanto, los programas de control de vectores dirigidos a las poblaciones de A. albopictus pueden verse comprometidos.

Near-infrared spectroscopy and microstructure of the scales of Sabethes ( Sabethes ) albiprivus (Diptera: Culicidae)

ABSTRACT Near-infrared spectroscopy and microstructure of the scales of Sabethes (Sabethes) albiprivus (Diptera: Culicidae). Sabethes (Sabethes) albiprivus Theobald individuals vary considerably in size and color of the reflections of the scales on their thorax, abdomen, antepronotal lobes and occiput. The goal of this study was to investigate and to characterize the differences in the color of the scales among preserved specimens and to analyze the differences in the microstructures of the scales that cover their bodies using near-infrared spectroscopy, and to evaluate whether the latter is efficient in distinguishing the populations. A total of 201 adult females were analyzed for the characterization of color patterns. In addition, absorbance spectra and scanning electron microscope images were obtained from them. As a result of color analysis, two variations were identified, one represented by specimens with yellow or green scales and the other with blue or purple scales. The same two variations were corroborated using NIRS. Analysis of the microstructure of the scales lining the mesonotum, occiput and antepronotal lobes resulted in the same variations. The three methodologies, near-infrared spectroscopy, scanning electron microscopy and coloration of the reflections of the scales revealed two variations within Sa. albiprivus.

Improvement of a RT-PCR assay for Yellow Fever virus genome detection

The aim of the present study was to describe an improved protocol of reverse transcription polymerase chain reaction (RT-PCR) for Yellow Fever virus genome detection. A strain of ribonucleic acid of Yellow Fever virus was submitted to the improved protocol of RT-PCR and the amplicons were visualized under ultraviolet transilluminator, purifed and sequenced. The nucleotide sequence obtained was compared with sequences available in GenBank using the tblastx tool. The amplicons produced by the strain of ribonucleic acid of Yellow Fever virus exhibited fragments of 400 and 800 base pairs and the consensus sequence exhibited a similarity of 100% with Yellow Fever virus sequences recorded in GenBank. The improved protocol described in this study allowed Yellow Fever virus genome detection and enabled the elimination of the nested-PCR step, which has been frequently associated with contamination. In addition, it reduced the time of reaction, the cost of reagents and the possibility of sample contamination. New methods of investigating these infections must be elaborated and a continuous vigilance of these viruses in their different vectors and hosts is required to avoid negative impacts on human health, tourism and trade.(AU)

Contrasting patterns of insecticide resistance and knockdown resistance (kdr) in Aedes aegypti populations from Jacarezinho (Brazil) after a Dengue Outbreak

ABSTRACT After a dengue outbreak, the knowledge on the extent, distribution and mechanisms of insecticide resistance is essential for successful insecticide-based dengue control interventions. Therefore, we evaluated the potential changes to insecticide resistance in natural Aedes aegypti populations to Organophosphates (OP) and Pyrethroids (PY) after chemical vector control interventions. After a Dengue outbreak in 2010, A. aegypti mosquitoes from the urban area of Jacarezinho (Paraná, Brazil) were collected in 2011 and 2012. Insecticide resistance to OP Temephos was assessed in 2011 and 2012 by dose–response bioassays adopting WHO-based protocols. Additionally, in both sampling, PY resistance was also investigated by the Val1016Ile mutation genotyping. In 2011, a random collection of mosquitoes was carried out; while in 2012, the urban area was divided into four regions where mosquitoes were sampled randomly. Bioassays conducted with larvae in 2011 (82 ± 10%; RR95 = 3.6) and 2012 (95 ± 3%; RR95 = 2.5) indicated an incipient altered susceptibility to Temephos. On the other hand, the Val1016IIe mutation analysis in 2011, presented frequencies of the 1016Ilekdr allele equal to 80%. Nevertheless, in 2012, when the urban area of Jacarezinho was analyzed as a single unit, the frequency of the mutant allele was 70%. Additionally, the distribution analysis of the Val1016Ile mutation in 2012 showed the mutant allele frequencies ≥60% in all regions. These outcomes indicated the necessity of developing alternative strategies such as insecticide rotations for delaying the evolution of resistance.

Morpho-histological characterization of immature of the bioindicator midge Chironomus sancticaroli Strixino and Strixino (Diptera, Chironomidae)

ABSTRACTChironomidae immature are used as bioindicators of sediment quality in aquatic ecosystems and ecotoxicological assays. Histological descriptions for this family are outdated and limited and there are no studies with Neotropical species. The aim of this study was to describe the tissue architecture of several organs of the larva of Chironomus sancticaroli. For the description of the histological pattern, the larvae were fixed in Duboscq solution for insects at 56 °C, followed by routine histologic processing, infiltration in paraffin, and the sections were stained with Hematoxylin–Eosin. After examining the slides, the tube digestive, salivary gland, excretory, nervous, endocrine, circulatory, and integumentary systems and fat body were histologically characterized. The histology allows evaluation of cell morphology, and for being not expensive and easily accessible can be routinely used in biomonitoring. In addition, is a useful tool in ecotoxicological assays and allow to evaluate biomarkers at tissue and cell levels.

Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae)

Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae). Considering that some species of Culicidae are vectors of pathogens, both the knowledge of the diversity of the mosquito fauna and how some environment factors influence in it, are important subjects. In order to address the composition of Culicidae species in a forest reserve in southern Atlantic Forest, we compared biotic and abiotic environmental determinants and how they were associated with the occurrence of species between sunset and sunrise. The level of conservation of the area was also considered. The investigation was carried out at Reserva Natural do Morro da Mina, in Antonina, state of Paraná, Brazil. We performed sixteen mosquito collections employing Shannon traps at three-hour intervals, from July 2008 to June 2009. The characterization of the area was determined using ecological indices of diversity, evenness, dominance and similarity. We compared the frequency of specimens with abiotic variables, i.e., temperature, relative humidity and pluviosity. Seven thousand four hundred ten mosquito females were captured. They belong to 48 species of 12 genera. The most abundant genera were Anopheles, Culex, Coquillettidia, Aedes and Runchomyia. Among the species, the most abundant was Anopheles cruzii, the primary vector of Plasmodium spp. in the Atlantic Forest. Results of the analyses showed that the abiotic variables we tested did not influence the occurrence of species, although certain values suggested that there was an optimum range for the occurrence of culicid species. It was possible to detect the presence of species of Culicidae with different epidemiologic profiles and habitat preference.

Genetic diversity of dengue virus serotypes 1 and 2 in the State of Paraná, Brazil, based on a fragment of the capsid/premembrane junction region / Diversidade genética dos vírus dengue sorotipos 1 e 2, no Estado do Paraná, Brasil, baseada no fragmento da junção do gene capsídeo/pré-membrana

INTRODUCTION: The precise identification of the genetic variants of the dengue virus is important to understand its dispersion and virulence patterns and to identify the strains responsible for epidemic outbreaks. This study investigated the genetic variants of the capsid-premembrane junction region fragment in the dengue virus serotypes 1 and 2 (DENV1-2). METHODS: Samples from 11 municipalities in the State of Paraná, Brazil, were provided by the Central Laboratory of Paraná. They were isolated from the cell culture line C6/36 (Aedes albopictus) and were positive for indirect immunofluorescence. Ribonucleic acid (RNA) extracted from these samples was submitted to the reverse transcription polymerase chain reaction (RT-PCR) and nested PCR. RESULTS: RT-PCR revealed that 4 of the samples were co-infected with both serotypes. The isolated DENV-1 sequences were 95-100% similar to the sequences of other serotype 1 strains deposited in GenBank. Similarly, the isolated DENV-2 sequences were 98-100% similar to other serotype 2 sequences in GenBank. According to our neighbor-joining tree, all strains obtained in this study belonged to genotype V of DENV-1. The DENV-2 strains, by contrast, belonged to the American/Asian genotypes. CONCLUSIONS: The monitoring of circulating strains is an important tool to detect the migration of virus subtypes involved in dengue epidemics.

INTRODUÇÃO:A identificação precisa da variante genética do vírus da dengue é importante para compreender a dispersão, virulência e identificação das cepas responsáveis pelas epidemias. O objetivo da pesquisa foi investigar a variação genética do fragmento da junção do gene capsídeo/pré-membrana dos sorotipos 1 e 2. MÉTODOS: Amostras de onze municípios do Estado Paraná, Brasil, foram cedidas pelo Laboratório Central do Paraná e consistiam em isolados de cultura de células da linhagem C6/36 (Aedes albopictus), positivos para técnica de imunofluorescência indireta. O Ribonucleic acid (RNA) dessas amostras foi extraído, seguido da transcrição reversa, reação em cadeia da polimerase (PCR) e nested PCR. RESULTADOS: Co-infecção por DENV-1 e 2 (virus da dengue 1 e 2) foi observada em quatro pacientes, através da técnica Reverse transcriptase-polymerase chain reaction (RT-PCR). Para o DENV-1 a porcentagem de similaridade variou de 95 a 100% comparando com cepas do Genbank. Para o DENV-2 a porcentagem de similaridade variou de 98 a 100%. De acordo com o cladograma gerado, todas as cepas deste estudo se agruparam no genótipo V para DENV-1. Para o DENV-2 foi encontrada a cepa referente ao genótipo asiático/americano. CONCLUSÕES: O monitoramento das cepas circulantes torna-se uma ferramenta importante na detecção da migração dos subtipos do vírus da dengue envolvidos em epidemias.

Detecção do vírus da dengue em populações naturais de mosquitos / Detection of dengue virus in natural populations of mosquitoes

A dengue é causada por um Flavivirus que apresenta elevada diversidade genética, com quatro sorotipos e vários genótipos. A enfermidade é endêmica na maioria dos países das Américas, e as fêmeas de Aedes (Stegomyia) aegypti (Linnaeus, 1762) são as únicas transmissoras, com importância epidemiológica. Um único mosquito infectado permanece assim pelo resto de sua vida, podendo infectar múltiplos hospedeiros humanos. Com a detecção do vírus da dengue em mosquitos, podemos revelar o sorotipo circulante ou a entrada de um novo sorotipo em uma determinada região, sem quaisquer implicações éticas, além de apresentar reprodutibilidade dos resultados. Esta revisão aborda as técnicas para detecção viral em mosquitos, suas vantagens e limitações, bem como as pesquisas já realizadas com populações naturais de Aedes aegypti.

Dengue is caused by Flavivirus which exhibits high genetic diversity, with four serotypes and various genotypes. The disease is endemic in most countries in the Americas, and the female Aedes (Stegomyia) aegypti (Linnaeus, 1762) are the only transmitters of epidemiological importance. A single infected mosquito remains so for the rest of his life and can infect multiple human hosts. For dengue virus detection in mosquitoes, the circulating serotype can be revealed or detect an entry of a new serotype in the region, without any ethical implications, and reproducible results. This review covers the techniques for detecting virus in mosquitoes, their advantages and limitations, as well as previous studies with natural populations of Aedes aegypti.

El dengue es causado por un Flavivirus que presenta una alta diversidad genética, cuatro serotipos y varios genotipos. Esta enfermedad es endémica en la mayoría de los países del continente Americano y sólo las hembras de Aedes (Stegomyia) aegypti (Linnaeus, 1762) son las transmisoras de esta enfermedad de importancia epidemiológica. Un único mosquito infectado permanece así por el resto de su vida pudiendo infectar múltiples hospederos humanos. El detectar el serotipo de virus de dengue presente en los mosquitos permite conocer, ya sea, el serotipo circulante o el ingreso de un nuevo serotipo a una determinada región sin ningún tipo de implicaciones éticas presentando así resultados reproducibles. Ésta revisión aborda las técnicas de detección viral en mosquitos, sus ventajas y limitaciones, así como estudios previos con poblaciones naturales de Aedes aegypti.

Aplicação de marcadores microssatélites para o estudo de Culicidae (Diptera): revisão com especial referência a Haemagogus / Aplicación de marcadores microsatélites para el estudio de Culicidae (Diptera): una revisión con especial referencia a Haemagogus / Application of microsatellite markers for the study of Culicidae (Diptera): a review with special reference to Haemagogus

Marcadores moleculares microssatélites se caracterizam pela neutralidade, alto polimorfismo e elevada abundância com ampla distribuição pelo genoma de eucariotos. O seu emprego em estudos relacionados a espécies de mosquitos vetoras é ideal para o mapeamento genético e físico, para a identificação e discriminação de genótipos e estudos de genética de populações. Esta revisão sumariza e fornece informações sobre estudos envolvendo culicídeos através da utilização de marcadores microssatélites e propõe sugestões de pesquisas para uma melhor compreensão da biologia e dinâmica de transmissão do vírus da febre amarela por espécies do gênero Haemagogus.

Los marcadores moleculares microsatelitales se caracterizan por su neutralidad, alto polimorfismo y elevada abundancia con amplia distribución en el genoma de eucariotas. Su empleo en estudios relacionados a especies de mosquitos vectores es ideal para el mapeo genético y físico, para la identificación y discriminación de genotipos y estudios de genética de poblaciones. Esta revisión sintetiza y provee información sobre estudios de mosquitos que utilizan marcadores microsatelitales y propone nuevas líneas de investigación para una mejor comprensión de la biología y dinámica de transmisión del virus de la Fiebre Amarilla por especies del género Haemagogus.

Microsatellite molecular markers are characterized by neutrality, high polymorphism and wide distribution with high abundance in the genome of eukaryotes. Its use in studies related to species of mosquito vectors is ideal for genetic and physical mapping, for the identification and discrimination of genotypes and genetic studies of populations. This review summarizes and provides information on studies involving mosquitoes by using microsatellite markers and suggests avenues of research to better understand the biology and dynamics of transmission of Yellow Fever virus by Haemagogus mosquitoes.

Parapentaneura bentogomensis Stur, Fittkau et Serrano (Diptera, Chironomidae, Tanypodinae) taken in Southeastern, Brazil: additional characters and modified generic diagnosis / Parapentaneura bentogomensis Stur, Fittkau et Serrano (Diptera, Chironomidae, Tanypodinae) da região Sudeste do Brasil: caracteres adicionais e diagnose genérica modificada

The genus Parapentaneura was established in 2006 and is composed of a single species, Parapentaneura bentogomensis, originally from Mato Grosso State. This species was collected in São Paulo State and is thus redescribed. The specimens from both localities were compared, adding new characters to the description of the species and emending the genus diagnosis. The new record increases considerably the geographical distribution of Parapentaneura.

O gênero Parapentaneura foi estabelecido em 2006 e apresenta somente uma espécie, Parapentaneura bentogomensis, proveniente do Estado do Mato Grosso. Esta espécie foi coletada no Estado de São Paulo e então redescrita detalhadamente, apresentando caracteres adicionais. Os espécimes de ambas as localidades foram comparados, possibilitando o aperfeiçoamento da diagnose do gênero. O novo registro amplia consideravelmente a distribuição geográfica de Parapentaneura.

Developmental time of immature forms of Sabethes aurescens Lutz (Diptera, Culicidae) from artificially perforated bamboo in the rain forest of southern Brazil / Tempo de desenvolvimento de formas imaturas de Sabethes aurescens Lutz (Diptera, Culicidae) provenientes de bambus artificialmente perfurados em floresta atlântica do sul do Brasil

The development time of the immature forms of Sabethes aurescens Lutz, 1905, from perforated bamboo in the southern Brazil rain forest was studied under laboratory conditions. Mean development periods were 5±2.23, 10±5.20, 14±8.26, 36±13.90 and 9±2.43 days, respectively, for the four larval instars and pupae. The 4th instar of females was longer than that of males. Implications of the long development time of the immature forms of Sa. aurescens are discussed.

O tempo de desenvolvimento de formas imaturas de Sabethes aurescens Lutz, 1905 de bambus perfurados da floresta atlântica do sul do Brasil foi estudado em condições de laboratório. O período médio de desenvolvimento foi de 5±2,23; 10±5,20; 14±8,26; 36±13,90 e 9±2,43 dias respectivamente, para os quatro instares larvais e pupa. O 4º instar das fêmeas foi mais longo do que o dos machos. Implicações do longo tempo de desenvolvimento das formas imaturas de Sa. aurescens são discutidas.

New records of mosquito species (Diptera: Culicidae) for Santa Catarina and Paraná (Brazil) / Novos registros de espécies de mosquitos (Diptera: Culicidae) em Santa Catarina e Paraná (Brasil)

We provide eight new mosquito species records for Santa Catarina (Limatus flavisetosus Oliveira Castro 1935, Mansonia flaveola (Coquillett 1906), Ma. titillans (Walker 1848), Psorophora forceps Cerqueira 1939, Sabethes xyphydes Harbach 1994, Toxorhynchites bambusicolus (Lutz & Neiva 1913), Tx. theobaldi (Dyar & Knab 1906) and Wyeomyia lassalli Bonne-Wepster & Bonne 1921) and three for Paraná (Ochlerotatus argyrothorax Bonne-Wepster & Bonne 1920, Uranotaenia pallidoventer Theobald 1903 and Wyeomyia pilicauda Root 1928). Additionally, we list all species in these eight genera recorded previously in the two states. The known distribution and possible epidemiological implications of the new species records are discussed.

Relatamos o primeiro encontro de oito espécies de mosquitos para Santa Catarina (Limatus flavisetosus Oliveira Castro 1935, Mansonia flaveola (Coquillett 1906), Ma. titillans (Walker 1848), Psorophora fórceps Cerqueira 1939, Sabethes xyphydes Harbach 1994, Toxorhynchites bambusicolus (Lutz & Neiva 1913), Tx. theobaldi (Dyar & Knab 1906) e Wyeomyia lassalli Bonne-Wepster & Bonne 1921) e três para o Paraná (Ochlerotatus argyrothorax Bonne-Wepster & Bonne 1920, Uranotaenia pallidoventer Theobald 1903 e Wyeomyia pilicauda Root 1928). Adicionalmente, apresentamos lista de todas as espécies destes oito gêneros com registro nos dois estados. A distribuição conhecida das espécies e sua possível importância epidemiológica são discutidas.

Dynamics of the control of Aedes (Stegomyia) aegypti Linnaeus (Diptera, Culicidae) by Bacillus thuringiensis var israelensis, related with temperature, density and concentration of insecticide

The dynamics of the control of Aedes (Stegomyia) aegypti Linnaeus, (Diptera, Culicidae) by Bacillus thuringiensis var israelensis has been related with the temperature, density and concentration of the insecticide. A mathematical model for biological control of Aedes aegypti with Bacillus thuringiensis var israelensis (Bti) was constructed by using data from the literature regarding the biology of the vector. The life cycle was described by differential equations. Lethal concentrations (LC50 and LC95) of Bti were determined in the laboratory under different experimental conditions. Temperature, colony, larvae density and bioinsecticide concentration presented marked differences in the analysis of the whole set of variables; although when analyzed individually, only the temperature and concentration showed changes. The simulations indicated an inverse relationship between temperature and mosquito population, nonetheless, faster growth of populations is reached at higher temperatures. As conclusion, the model suggests the use of integrated control strategies for immature and adult mosquitoes in order to achieve a reduction of Aedes aegypti.

Foi elaborado um modelo matemático do controle biológico de Aedes aegypti com foco em Bacillus thuringiensis var israelensis (Bti). Na construção do modelo foram utilizados dados da literatura sobre a biologia do vetor, no qual o ciclo de vida foi descrito através de equações diferenciais. As concentrações letais (CL50 e CL95) do Bti foram determinadas no laboratório sob diferentes condições experimentais. As variáveis temperatura, colônia, densidade de larvas e concentração do bioinseticida acusaram diferenças significativas quando analisadas no modelo geral, porém quando analisadas individualmente, apenas a temperatura e concentração apresentaram diferenças. As simulações do modelo indicam que a temperatura afeta inversamente a produção de indivíduos e que os pontos máximos de produção de mosquitos são atingidos mais rápido a temperaturas maiores. Concluímos, com a simulação do modelo, que estratégias integradas de controle de imaturos e adultos devem ser utilizadas para atingir redução expressiva da população de Aedes aegypti.

PCR-RAPD and PCR-RFLP polymorphisms detected in Anopheles cruzii (Diptera, Culicidae)

The aim of the present study was to examine genetic variability in populations of An. cruzii by employing PCR-RAPD and PCR-RFLP markers. All analyses were carried out using individuals of the F1 generation of wild caught females obtained in Santa Catarina State (Florianópolis and São Francisco do Sul), Paraná State (Morretes, Paranaguá and Guaratuba) and São Paulo State (Cananéia). In the PCR-RAPD experiments, seven primers were used for comparisons within and among populations. The restriction profile of the ITS2 including a fragment of both 5.8S and 28S regions of the rDNA was obtained with the enzymes BstUI, HaeIII, TaqI, HhaI, Sau96I, HinfI, HincII and NruI. The PCR-RAPD method detected a large number of polymorphic bands. Genetic distance among populations of An. cruzii varied from 0,0214 to 0,0673, suggesting that all individuals used in the analyses belong to a single species. The number of migrants per generation (Nm) was 4.3, showing the existence of gene flow among populations. The restriction profile of the ITS2, 5.8S and 28S gene regions was similar in all An. cruzii samples, whereas the results obtained by using HhaI and NruI are indicative that the individuals analyzed have nucleotide sequences distinct from those of An. cruzii samples from Peruíbe and Juquiazinho deposited in GenBank.

O objetivo desse trabalho foi analisar a variabilidade genética em populações de An. cruzii utilizando as técnicas PCR-RAPD e PCR-RFLP. As análises foram realizadas a partir de adultos da geração F1 de fêmeas coletadas nos estados de Santa Catarina (Florianópolis e São Francisco do Sul), Paraná (Morretes, Paranaguá e Guaratuba) e São Paulo (Cananéia). Na PCR-RAPD, sete iniciadores foram utilizados para comparação dentro e entre populações. Os perfis de restrição da região ITS2 e parte do genes 5.8S e 28S foram obtidos com as enzimas BstUI, HaeIII, TaqI, HhaI, Sau96I, HinfI, HincII e NruI. Utilizando-se a técnica PCR-RAPD, elevado número de bandas polimórficas foi detectado. As distâncias genéticas entre as populações variaram de 0,0214 a 0,0673, sugerindo que as amostras representam uma única espécie. O número de migrantes por geração (Nm) foi de 4,3, indicando a existência de fluxo gênico entre as populações. Os padrões de restrição da região ITS2 foram semelhantes para todas as amostras de An. cruzii, entretanto, os resultados obtidos com HhaI e NruI indicam que os indivíduos analisados apresentam seqüências diferentes daquelas disponíveis no GenBank para as populações de Peruíbe e Juquiazinho.

Susceptibilidade de Aedes aegypti aos inseticidas temephos e cipermetrina, Brasil / Susceptibility of Aedes aegypti to temephos and cypermethrin insecticides, Brazil

Realizaram-se bioensaios para detectar a susceptibilidade de Aedes aegypti aos inseticidas químicos, temefós e cipermetrina. Os resultados mostraram que esta espécie é suscetível a temefós e apresenta resistência a cipermetrinae.