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Background: We investigated the ecological differentiation of two members of the Culex pipiens complex, Cx. p. pipiens form pipiens and Cx. p. pipiens form molestus in three sites, El-Kala, M'Sila and Tinerkouk in Algeria. These two forms are the most widespread mosquito vectors in temperate regions exhibiting important behavioural and physiological differences. Nevertheless, this group of potential vectors has been poorly studied, particularly in North Africa. Methods: Ten larval populations of Cx. p. pipiens were sampled from various above- and underground habitats in three zones representing the three bioclimatic regions in Algeria. The reproduction characteristics were also investigated in the laboratory to define the rates of autogeny and stenogamy. Identification of Cx. p. pipiens members present in Algeria was achieved using a molecular analysis with the microsatellite CQ11 locus. Results: We detected larvae of Cx. p. pipiens in all areas suggesting that the species is a ubiquitous mosquito well adapted to various environments. To our knowledge, this study provides the first molecular evidence of the presence of the Cx. p. pipiens form molestus and hybrids (molestus/pipiens) in Algeria with a high proportion of molestus form (48.3 %) in comparison with hybrids (36.8 %) and pipiens form (14.9 %). Conclusions: Some unexpected correlations between the proportion of forms pipiens, molestus and hybrids, and mosquito biological characteristics were observed suggesting some epigenetic effects controlling Cx. p. pipiens mating and reproduction. Consequences for pathogen transmission are discussed. [ABSTRACT FROM AUTHOR]

The spore productivity and insecticidal activity of two opportunistic insect pathogenicAspergillusspecies (namely:Aspergillus clavatusDesmazieres andAspergillus flavusLink (Ascomycota: Eurotiales, Trichocomaceae)) were compared toMetarhizium anisopliaesensu lato (Metchnikoff) Sorokin (Ascomycota: Hypocreales, Clavicipitaceae) for mosquito (Diptera: Culicidae) control. The production of aerial spores on wheat bran and white rice was investigated in solid-, semi-solid-, and liquid-state media supplemented with a nutritive solution. Wheat bran-based media increased the spore yield in solid-state from three to sevenfold:A. clavatusproduced 48.4 ± 5.2 and 15.7 ± 1.6 × 108spores/g,A. flavusproduced 22.3 ± 4.1 and 3.1 ± 2.5 × 108spores/g, andM. anisopliaeproduced 39.6 ± 6.5 and 13.1 ± 2.6 × 108spores/g of wheat bran or white rice, respectively.A. clavatus,A. flavusandM. anisopliaespores harvested from wheat bran-based solid-state media showed lethal concentrations (LC50) of 1.1, 1.8, and 1.3 × 108spores/ml againstCulex quinquefasciatusSay larvae in 72 h. BecauseA. clavatusandM. anisopliaedisplayed similar features when cultured under these conditions, our results suggest that insect pathogenicAspergillusspecies may be as productive and virulent against mosquito larvae as a well-recognised entomopathogenic fungus. [ABSTRACT FROM PUBLISHER]

Since its first report in 2000, the invasive mosquito Aedes albopictus was not found any more during the different entomological inspections performed at its place of introduction in Belgium between 2001 and 2012. In July 2013, one adult male was captured at the same site (a platform of imported used tires located in Vrasene, Oost-Vlaanderen Province), during a monitoring using CO2-baited trap. This finding suggests the reintroduction of the species in Belgium via the used tire trade., (© S. Boukraa et al., published by EDP Sciences, 2013.)