Aedes aegypti pharate 1st instar quiescence: A case for anticipatory reproductive plasticity

Aedes aegypti mosquitoes use pharate 1st instar quiescence to cope with fluctuations in water availability hosting a fully developed 1st instar larvae within the chorion. The duration of this quiescence has been shown to affect larval fitness. This study sought to determine if an extended egg quiescence can elicit a plastic response resulting in an adult phenotype distinct from adults reared from short quiescence eggs. Our findings indicate that extended pharate 1st instar quiescence affects the performance and reproductive fitness of the adult female mosquito as well as the nutritional status of its progeny via maternal effects in an adaptive manner. This study demonstrates that phenotypic plasticity results as a consequence of the duration of pharate 1st instar quiescence and alternative phenotypes may exist for this mosquito with quiescence serving as a cue possibly signaling the environmental conditions that follow a dry period. These findings have implications for A. aegypti’s success as a vector, geographic distribution, vector capacity and control.

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► Extended quiescence serves as an environmental cue predicting adult environment.
► Pharate 1st instar extended quiescence modifies adult phenotype.
► Adult response to larval stress differs between phenotypes.
► Costs of pharate 1st instar extended quiescence are reflected in maternal effects.