Impact of Thermal Variation on Egg Hatching and the Life Cycle of Aedes (Protomacleaya) terrens (Diptera: Culicidae) in a Laboratory Environment

TL;DR

This study examines how different temperatures affect the hatching and development of Aedes terrens mosquitoes, which can transmit the chikungunya virus.

Contribution

The study identifies optimal temperatures for egg hatching and development stages of Ae. terrens, highlighting temperature's role in vector biology.

Findings

The highest hatching rate occurred at 25 °C, with an optimal point around 27 °C.

Temperature significantly reduced the duration of each developmental stage, with the fastest cycle at 30 °C.

Temperature variations influence the development, survival, and virus transmission potential of Ae. terrens.

Abstract

Evaluating the development process of mosquito species under the influence of temperature is essential for understanding their ecology and geographical distribution, as well as assessing their potential as vectors of pathogens. Aedes (Protomacleaya) terrens, a species recognized for its susceptibility and competence in transmitting the chikungunya virus, serves as a relevant model for research in this context. This study aimed to analyze the influence of temperature on egg hatching and the development cycle of this species to expand knowledge on its biology and implications for public health. During the experiment, 800 eggs were used, collected through 10 ovitraps in a forest remnant located in Uruaçu, Goiás, Brazil. The total number of eggs was divided into four groups, exposed to constant temperatures of 15 ± 2 °C, 20 ± 2 °C, 25 ± 2 °C, and 30 ± 2 °C. After hatching, first-instar larvae were individually separated and monitored daily under controlled conditions until adult emergence. The highest hatching rate occurred at 25 °C, showing an optimal point around 27 °C. Throughout development, temperature significantly reduced the duration of each stage, with the fastest complete cycle at 30 °C, a difference of approximately 10–12 days when compared to 20 °C and approximately 47 days when compared to 25 °C. These results offer valuable insights into the temperature sensitivity of Ae. terrens across its developmental stages, suggesting that each stage has its own optimal temperature. Thus, small variations in responses to environmental conditions and differentiation between sexes may become more pronounced throughout development. In this sense, temperature can affect not only the development and survival of dipterans but also the capacity for virus transmission, as the pathogen influences the reproduction rate and longevity of the vectors.

Figures