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Wing diagnostic characters for Culex quinquefasciatus and Culex nigripalpus (Diptera, Culicidae)
Vidal, Paloma Oliveira;Peruzin, Maria Cristina;Suesdek, Lincoln;
Revista Brasileira de Entomologia , 2011, DOI: 10.1590/S0085-56262011000100022
Abstract: wing diagnostic characters for culex quinquefasciatus and culex nigripalpus (diptera, culicidae). culex quinquefasciatus and culex nigripalpus are mosquitoes of public health interest, which can occur sympatrically in urban and semi-urban localities. morphological identification of these species may be difficult when specimens are not perfectly preserved. in order to suggest an alternative taxonomical diagnosis, wings of these species were comparatively characterized using geometric morphometrics. both species could be distinguished by wing shape with accuracy rates ranging from 85-100%. present results indicate that one can identify these species relying only on wing characters when traditional taxonomical characters are not visible.
Culex quinquefasciatus Storage Proteins  [PDF]
Larissa A. Martins, Andréa C. Foga?a, A. Tania Bijovsky, Rebeca Carballar-Lejarazú, Osvaldo Marinotti, André F. Cardoso
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0077664
Abstract: Insect storage proteins accumulate at high levels during larval development of holometabolous insects. During metamorphosis they are degraded, supplying energy and amino acids for the completion of adult development. The genome of Culex quinquefasciatus contains eleven storage protein-coding genes. Their transcripts are more abundant in larvae than in pupae and in adults. In fact, only four of these genes are transcribed in adults, two of which in blood-fed adult females but not in adult males. Transcripts corresponding to all Cx. quinquefasciatus storage proteins were detected by RT-PCR, while mass spectrometric analysis of larval and pupal proteins identified all storage proteins with the exception of one encoded by Cq LSP1.8. Our results indicate that the identified Cx. quinquefasciatus storage protein-coding genes are candidates for identifying regulatory sequences for the development of molecular tools for vector control.
Laboratory and field evaluation of an oviposition trap for Culex quinquefasciatus(Diptera: Culicidae)
Barbosa, Rosangela MR;Souto, Antonio;Eiras, Alvaro E;Regis, Lêda;
Memórias do Instituto Oswaldo Cruz , 2007, DOI: 10.1590/S0074-02762007005000058
Abstract: an ovitrap (br-ovt) based on physical and chemical stimuli for attracting gravid culex quinquefasciatus (diptera: culicidae) females was developed and evaluated under laboratory and field conditions. attractants were assayed using alternative chamber bioassays prior to being used in the br-ovt oviposition trap. a significant preference of gravid females for sites containing conspecific egg rafts was observed, as a response to the natural oviposition pheromone, as well as for sites treated with the synthetic pheromone erythro-6-acetoxy-5-hexadecanolide. five- to 20-day old grass infusion was strongly attractive to gravid females for laying eggs. on the other hand, entomopathogenic bacillus sphaericus (bs) did not influence the choice of an oviposition site when used in combination with grass infusion and can therefore be used as a larvicide in ovitraps. results from field trials showed that the br-ovt with grass infusion and with or without bs works as a preferred oviposition site for cx. quinquefasciatus. the br-ovt was more effective for egg collection when placed indoors and comparison with the number of egg rafts laid in cesspits over 40 days indicates that this very simple ovitrap may be a useful tool for monitoring populations of the most important of the vectors of bancroftian filariasis.
Laboratory Evaluation of Excocearia indica (Willd.) Muell. Arg Seed Kernel Extract Against Common Filarial Vector, Culex quinquefasciatus Say (Diptera:Culicidae) Larvae  [PDF]
Khondkar Ehteshamul Kabir,M.Mahbul Hasan,M.Safinur Rahman,M.Ashik Mosaddik
Pakistan Journal of Biological Sciences , 1999,
Abstract: The ethyl acetate extract of Excoecaria indica Willd. seed kernel were evaluated for larvicidal activity against common fiarial vector, Culex quinquefasciatus Say (Diptera: Culicidae) at different instars under laboratory conditions. The LD50 values were 19.36, 17.76, 15.57 and 11.96; 16.28, 13.87, 13.14 and 10.99; 30.23, 28.32, 27.03 and 47.29, 45.71, 43.74 and 36.90 mg/10ml for 1st, 2nd, 3rd and 4th instar larvae Culex quinquefasciatus at 3, 6, 12 and 24 hour post exposure respectively. The results also showed that the late instar larvae were more resistant to the extract than those of early instars.
Effects of ivermectin on Culex quinquefasciatus larvae
Freitas, Ricardo Miguel Costa de;Faria, Mágda de Abreu;Alves, Stênio Nunes;Melo, Alan Lane de;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1996, DOI: 10.1590/S0036-46651996000400010
Abstract: the effects of ivermectin, a semi-synthetic drug widely used for treatment of livestock parasitic diseases, were observed on culex quinquefasciatus larvae. toxic effects and mortality evaluation were carried out after 5, 15, 30 and 60 minutes of exposure to 1, 5 or 10 ppm of ivermectin solutions. observations were made 24 and 48 hours after the beginning of the experiment, and loss of mobility, progressive paralysis and high mortality of larvae were recorded. the observed effects of ivermectin on the mosquito larvae is probably correlated with chloride channel activation on cell membranes.
Atividade predatória de Helobdella triserialis lineata (Hirudinea: Glossiphonidae) sobre formas imaturas de Aedes fluviatilis e Culex quinquefasciatus (Diptera: Culicidae) em laboratório
C?nsoli,Rotraut Anna Gertrud Bohlmann; Guimar?es,Carlos Tito; Souza,Cecília Pereira de; Santos,Bernadete de Souza;
Revista de Saúde Pública , 1984, DOI: 10.1590/S0034-89101984000500005
Abstract: experiments were conducted to determine the predatory activity of helobdella triserialis lineata (hirudinea: glossiphonidae) on eggs, larvae and pupae of aedes fluviatilis and culex quinquefasciatus (diptera: culicidae) in the laboratory, the influence of the leeches on selection, of ovipositing sites by the females of both species of mosquitoes, as well as the role of salinity and water depth in relation to predation were investigated. larvae and pupae of both species of mosquitoes were efficiently predated, but eggs were not touched. a significantly lower number of eggmasses of cx. quinquefasciatus were deposited on water containing leeches, but the same did not occur with ae. fluviatilis. the different depths of water investigated did not interfere with predation and only at concentrations above 3% nacl was predation considerably diminished.
The Relationship Between Lithology and Slope Morphology in the Tucson Mountains, Arizona.  [PDF]
Kamel Khanchoul,Robert Altschul
Anuário do Instituto de Geociências , 2008,
Abstract: The relationship between lithology and slope morphology is investigated at eight sites on granitic, andesitic, andsedimentary hillslopes in the Tucson Mountains, Arizona. Several methods are used in the study. Topographic profi lesare constructed. Skewness indices, slope length, and mean slope angles of the different slope profi les are computed andcompared with each other. Debris size analysis has permitted for some profi les, the determination of hillfront/piedmontjunctions. The nature and structural characteristics of the bedrock are the ones that determine the hillslope morphologyin this semi-arid region. There are, as a matter of fact, variations in profi les on the same bedrock nature but differentlyexposed. More precise morphologic studies have been also done in comparing the different lithologic pairs. They havepermitted to show some similarities in shapes. The granitic-andesitic slopes and andesiic-sedimentary slopes are thebest comparisons which show the relationship between lithology and slope morphology. The granitic-sedimentary sloperelationship is shown in the hillfront concavities, mountain front and piedmont mean slope angles.
Distribution and hybridization between Culex pipiens and Culex quinquefasciatus (Diptera: Culicidae) in Argentina
Almirón, Walter R.;Humeres, Silvia G.;Gardenal, Cristina N.;
Memórias do Instituto Oswaldo Cruz , 1995, DOI: 10.1590/S0074-02761995000400007
Abstract: to better undesrtand the distribution of culex pipiens and cx. quinquefasciatus in argentina, samples were collected from six localities situated in a north-south line from castelli (chaco province) to puerto madryn (chubut province). identification was based on the morphology of male genitalia. only cx. quinquefasciatus was found in castelli and esperanza, while in rosario, 95.3% belonged to this species and 4.7% represented hybrid forms. southern samples included only cx. pipiens. with the purpose of verfying if cx. pipiens and cx. quinquefasciatus hybridize, different crosses between the two species were perfomed. all crosses produced viable egg rafts. hatching ranged from 70 to 100%, except in one cross, female cx. pipiens x male cx. quinquefasciatus, where a high incompatibility was observed (11.1%hatch). the f1 hybrids obtained all crosses were fertile. the finding of hybrid forms in nature can be interpreted as evidence for subspecific status of cx. pipiens and cx. quinquefasciatus in argentina.
Experimental Infection of Culex (Culex) quinquefasciatus and Aedes (Stegomyia) aegypti with Wuchereria bancrofti
Calheiros, Cláudia ML;Fontes, Gilberto;Williams, Paul;Rocha, Eliana MM;
Memórias do Instituto Oswaldo Cruz , 1998, DOI: 10.1590/S0074-02761998000600029
Abstract: a study was conducted to determine the susceptibility of local strains of culex quinquefasciatus and aedes aegypti to infection with the strain of wuchereria bancrofti that occurs in maceió, state of alagoas, brazil. cx. quinquefasciatus blood fed simultaneously on the same microfilariae carrier ingested more blood and 2-3x more microfilariae than ae. aegypti. survival rates of both species of insects living for 21 days after blood feeding on microfilaraemic patients were not significantly different from the survival rates of mosquitoes that blood fed on amicrofilaraemic individuals. w. bancrofti parasites underwent normal development in cx. quinquefasciatus, with third stage larvae first being recorded on the 11th day post infection, and their numbers increasing thereafter. development of filariae in ae. aegypti did not proceed beyond the first larval stage, and there was a progressively increasing number of non-viable larvae with the passage of time. it is concluded that ae. aegypti is not involved in the transmission of w. bancrofti in maceió.
Experimental Infection of Culex (Culex) quinquefasciatus and Aedes (Stegomyia) aegypti with Wuchereria bancrofti  [cached]
Calheiros Cláudia ML,Fontes Gilberto,Williams Paul,Rocha Eliana MM
Memórias do Instituto Oswaldo Cruz , 1998,
Abstract: A study was conducted to determine the susceptibility of local strains of Culex quinquefasciatus and Aedes aegypti to infection with the strain of Wuchereria bancrofti that occurs in Maceió, State of Alagoas, Brazil. Cx. quinquefasciatus blood fed simultaneously on the same microfilariae carrier ingested more blood and 2-3x more microfilariae than Ae. aegypti. Survival rates of both species of insects living for 21 days after blood feeding on microfilaraemic patients were not significantly different from the survival rates of mosquitoes that blood fed on amicrofilaraemic individuals. W. bancrofti parasites underwent normal development in Cx. quinquefasciatus, with third stage larvae first being recorded on the 11th day post infection, and their numbers increasing thereafter. Development of filariae in Ae. aegypti did not proceed beyond the first larval stage, and there was a progressively increasing number of non-viable larvae with the passage of time. It is concluded that Ae. aegypti is not involved in the transmission of W. bancrofti in Maceió.
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