Larvae of Wyeomyia vanduzeei and of Wy. medioalbipes demonstrate an ability to develop to the pupal stage when their supply of food is limited and intermittent. They develop slowly, are able to prolong their development for weeks or months under nutritional stress and are able to complete their development after additional potential food is added to their environment. Analogies for this ability are suggested in larvae of other mosquito species, and the ecological significance is discussed.