A. verbasci has a life cycle ranging from 1–3 years, depending upon the environmental conditions. A study in 1958 found that temperature is able to affect larval development, concluding that the periods of incubation and pupation of A. verbasci decrease with increase of temperature (the life cycle is thus quickened with a moderate rise in temperature). Incubation decreased from 54 days at 15 °C to 12 days at 30 °C, and the pupation decreased from 89 days at 10 °C to 9 days at 25 °C. Relative humidity was shown to have little effect.
Larvae hatch from eggs in the spring and early summer, often in the nests of birds (including those of the house sparrow and house swift) or around stored fabrics.
Adults emerge between late May and early August (in England), flying to and feeding on the pollen and nectar of flowering plants. The life expectancy of the beetle is about two weeks. During this period, mating occurs and the eggs are laid, either close to the human environs or in bird nests, tree hollows and similar, dry places where larvae can find their food. Then the cycle begins anew.
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