Zika virus (ZIKV) is widely distributed in Brazil and the Northeast Region (NE) is the most affected zone, showing the highest incidence of microcephaly associated with ZIKV congenital infections worldwide. We report attempts to infect three populations of Culex quinquefasciatus from severely affected sites in the NE and Southeast Region (SE) of Brazil with three strains of ZIKV isolated from these localities. An Aedes aegypti population from the SE was used as a positive control. All tested Cx. quinquefasciatus populations were refractory to the ZIKV isolates. For these reasons, we believe Cx. quinquefasciatus should not be considered a potential vector of ZIKV in Brazil.

ABSTRACT. Floating population and comparison of collection method of Aedes (Stegomyia) aegypti (Diptera, Culicidae). Environmental factors act as regulators of expanding populations of Aedes aegypti (Linnaeus, 1762). This study aimed to evaluate the influence of temperature, relative air humidity, and pluviometric precipitation on the population dynamics of Ae. aegypti. The research was conducted at Boqueirão, Campina Grande and Remígio, state of Paraíba, comprising an 12-month period, using the method of collects per trap oviposition and larvae research. The population fluctuation of eggs and other immature forms as well as the infestation rates for eggs and larvae were correlated to climatic data using the Pearson correlation analysis. The chi-square and Tukey tests were used to compare the infestation between the study areas, and efficiency between research methods with trap oviposition and larval collecting. No correlations were found between climate variables and population dynamics of Ae. aegypti, neither with the indexes for oviposition trap (IAO) and Breteau (IB). The IAO was considered high, with an average of 54.9, 59.53 and 59.51%, while the IB was very low with an average of 1.55, 1.69 and 3.64, for the municipalities of Boqueirão, Campina Grande and Remígio, respectively. The chi-square analysis for the number of positive properties was highly significant, and we may infer that the collection method for oviposition trap was more efficient than the larvae research in the detection of infestation by Ae. aegypti. The results indicated that the evaluated factors cannot be considered isolated on ecological analysis of the distribution of this species, since correlations were not found between vector presence and climatic factors such as temperature, relative air humidity and rainfall. So in the ecological analysis of the distribution of Ae. aegypti should be considered the multiple constraints and determinants of its infestation. KEYWORDS.Vector, ecology, distribution, collection methodology. (Linnaeus, 1762). Este trabalho objetivou avaliar a influência da temperatura, umidade relativa do ar, e precipitação pluviométrica na flutuação populacional de Ae. aegypti. A pesquisa foi conduzida em Boqueirão, Campina Grande e Remígio, Estado da Paraíba, compreendendo um período de 12 meses, utilizando-se o método de coleta por armadilha de oviposição e de pesquisa larvária. A flutuação populacional de ovos e de outras formas imaturas, bem como os índices de infestação para ovos e larvas foi correlacionada com os dados climáticos utilizando-se a análise de correlação de Pearson. Os testes do qui-quadrado e de Tukey foram utilizados para comparar a infestação entre as áreas de estudo e a eficiência entre os métodos de pesquisas com armadilha de oviposição e de coletas de larvas. Não foram encontradas correlações entre as variáveis climáticas e a flutuação populacional de Ae. aegypti, nem com os índices para armadilha de oviposição (IAO) e de Breteau (IB). O IAO foi considerado alto, com média de 54,9; 59,53 e 59,5...

-We focused on the evaluation of the infl uence that the larval density have on the life cycle, size and fecundity of Aedes aegypti (L.). The bioassays were conducted at 26 ± 2ºC and at 12h light. Five larval densities (200, 500, 750, 1000 and 1250 larvae/l) and two feeding systems (one with a fi xed amount of 100 mg of food, and other with an amount of food proportional to the number of larvae/ tray) were tested. Egg and larval development time and survivorship, sex ratio, longevity, fecundity and the size of adults were evaluated on a daily basis. The life cycle of A. aegypti was signifi cantly affected by the density when offered 100 mg of food per tray. The period of larval development increased from 8.3 to 37.9 days whereas female fecundity and wing length decreased from 105.7 to 41.8 eggs/ female and from 4.6 mm to 3.6 mm, respectively, by changing from a density of 200 to 1250 larvae/l. Signifi cant differences of these variables were not detected when offering 1.9 mg of food per larvae, except for the size of the adults. Females emerged from rearing densities of 1250 larvae/l grew larger, with an average wing length of 5.2 mm.

Mosquito species of the subgenus Decamyia Dyar, 1919 of genus Wyeomyia Theobald, 1901 are known to have immature stages mostly associated with Heliconia plants. Currently, the subgenus includes five species, some of which are poorly characterized. Here, we redescribe and illustrate the larval, pupal and adult life stages of Wy. felicia (Dyar & Núñez Tovar, 1927). In addition, Wyeomyia monticola, a new species of Decamyia from Trinidad, close to Wy. felicia, is described. The new species can be distinguished by morphological characters of the male genitalia, larva and pupa.

Decamyia Dyar is a subgenus of Wyeomyia Theobald with three valid species. Wyeomyia rorotai Senevet, Chabelard & Abonnenc, a species originally described rather briefly in the subgenus Dendromyia, is without subgeneric position in the genus. In the present work, we redescribe Wy. rorotai in all life stages and formally define its taxonomic placement in the subgenus Decamyia by combining morphological and molecular analyses based on the mitochondrial cytochrome c oxidase subunit I gene. We also show that Decamyia is a rather homogeneous group of four species, i.e. Wy. ulocoma (Theobald), Wy. pseudopecten Dyar & Knab, Wy. felicia Dyar & Núñez Tovar and Wy. rorotai, the immature stages of which almost exclusively inhabit the flower bracts of Heliconiaceae.

A new species of the genus Wyeomyia, Wyeomyia (Decamyia) anthica sp. n., is described based on morphological and molecular analyses and is illustrated in larval, pupal and adult life stages. Among the four valid species of the subgenus Decamyia, the new species is closest to Wy. ulocoma (Theobald, 1903), from which it can be distinguished by morphological characters of the male genitalia, larval and pupal stages, and mitochondrial cytochrome c oxidase 1 gene sequence. Wyeomyia ulocoma is recorded from Brazil for the first time.

<p>Most models of soil C dynamics can be expressed by the differential vector equation:</p> <p><strong>dC(t)/dt = f(t).K.C(t) + b(t)</strong></p> <p>where each element of the vector C(t) represents a carbon compartment with intrinsic decomposition rate (usually fast, slow and passive); K is the transition matrix between the compartments (decomposition rates and decomposition partitioning); the scalar function f(t) is a forcing function of the decomposition rates modifiers (e.g. soil moisture and temperature); and b(t) is the vector with rates of external C inputs for each compartment. Considering the case where only total soil carbon is measured, only the sum of C in all compartments can be used for model evaluation, calibration and data assimilation. Also, in most compartmental models there are too many parameters to be adjusted, leading to identifiability problems. Although some parameters can be constrained according to the model’s assumptions, identifiability is still problematic except for the simplest compartmental models. By working on the differential equation, it is possible to deduce an explicit representation of the total carbon trajectory, in a way that the number of necessary empirical parameters is reduced, without loss of generality or need of further assumptions. In this work we propose such a representation for the total carbon trajectory whose generality embraces implicitly the mechanism of models as Century, RothC and CQESTR. The solution requires less parameters than the original models do but still allows mapping the original model parameters and decomposition modifiers functions onto the solution. Additionally, we show how the main processes of decomposition of soil organic matter can be represented by the terms of the solution found. Finally, we present the solution behavior under extreme conditions of temperature, humidity and initial stocks. We expect our general framework to help improving model’s calibration and data assimilation procedures.</p>