Winter Biology ofAedes albifasciatus(Diptera: Culicidae) from Córdoba, Argentina

Abstract

Host-seeking females of Aedes albifasciatus (Macquart) were collected from April to September 1997, kept under seminatural conditions, and offered sugar solution and blood. Daily survival of females ranged from 0.91 to 0.96, with blood fed females living longer than sugar fed females. Overall, 43% of engorged females completed a gonotrophic cycle, and 15% of them refed and completed a second gonotrophic cycle. The life expectancy of females emerging at the end of summer was longer than those that emerged during winter. Immature developmental time and the developmental threshold were estimated by regression. Embryo development was recorded during autumn, winter, and spring, with a duration of 5-9 d. The developmental threshold for eggs was estimated to be 2.28 degrees C. Egg mortality varied from 0.51 to 0.74. The development time for larva and pupa was between 16 and 29 d and was significantly correlated with temperature. The developmental threshold for larvae and pupae was estimated to be 4.75 degrees C. A greater proportion of females than males emerged when temperatures averaged < or = 18 degrees C. Larval and pupal mortality was high at temperatures below the developmental threshold. Aedes albifasciatus females remained gonotrophically active and immature development continued during winter in Córdoba (10 degrees C isotherm).

Long-term storage and viability of Ochlerotatus albifasciatus (Diptera: Culicidae)

“…After oviposition, females were withdrawn and the tubes sealed with plastic film to maintain humidity. Eggs remained at room temperature for over nine days to ensure complete maturity of embryos (Fava et al 2001).Batches (batch = group of eggs laid by a single female during one gonotrophic cycle) were pooled and randomly assigned to one of two treatments. Eggs from one treatment were kept at room temperature, and the other was stored in the dark at 5ºC.…”

“…After oviposition, females were withdrawn and the tubes sealed with plastic film to maintain humidity. Eggs remained at room temperature for over nine days to ensure complete maturity of embryos (Fava et al 2001).…”

Probable trajectories associated with the transport of Ochlerotatus albifasciatus during a strong wind event in Buenos Aires city (Argentina)

“…The time of development for immature forms and probable emergence of the O. albifasciatus adults was estimated 245 using mean daily temperature records from the same station and pre-existing models on development times related to temperature in the city of Buenos Aires, in the Province of Buenos Aires, and in the Province of Córdoba (Fontanarrosa et al, 2000;Fava et al, 2001;Campos and Sy, 2003). In addition, observations of the gender composition and behaviour of the adults found in the city on the day after the episode under study were taken into account.…”

“…Once the eggs have hatched, the development time of immature stages ranges from 6 days at 24°C to 32 days at 13°C (Ludueña Almeida and Gorla, 1995;Fontanarrosa et al, 2000;Fava et al, 2001;Campos and Sy, 2003). Great abundance peaks are the result of the synchronized emergence of adult floodwater mosquitoes (Horsfall, 1963).…”

Effect of diet composition on the development of the floodwater Mosquito Ochlerotatus (Ochletotatus) albifasciatus (Macquart) (Diptera: Culicidae)

“…For example, a low mortality was obtained when using powdered rabbit balanced food (Ludueña Almeida & Gorla 1995). On the contrary, a diet containing liver powder led to high mortality (Gleiser et al 2000b, Fava et al 2001. In an attempt to obtain adults in the laboratory, a high mortality was obtained when rearing larvae using yeast as food (Sy, pers.…”