title: pH tolerances and regulatory abilities of freshwater and euryhaline Aedine mosquito larvae.
abstract: The pH regulatory abilities of two members of the mosquito tribe Aedini, known to have dramatically different saline tolerances, are investigated. The freshwater mosquito Aedes aegypti and the euryhaline Ochlerotatus taeniorhynchus tolerate very similar pH ranges. Both species complete larval development in waters ranging from pH 4 to pH 11, but naïve larvae always die in water of pH 3 or 12. Across the pH range 4-11, the hemolymph pH of O. taeniorhynchus is maintained constant while that of A. aegypti varies by 0.1 pH units. The salt composition of the water (3.5 g l(-1) sea salt, 3.5 g l(-1) NaCl, or nominally salt-free) has no effect on the range of pH tolerated by A. aegypti. In both species, the effects of pH on larval growth and development are minor in comparison with the influence of species and sex. Acclimation of A. aegypti to pH 4 or 11 increases survival times in pH 3 or 12, respectively, and allows a small percentage of larvae to pupate successfully at these extreme pH values. Such acclimation does not compromise survival at the other pH extreme.
authors.affiliation: Department of Biological Sciences, Indiana University, South Bend, IN 46634-1700 USA. tclark2@iusb.edu
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Clark
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Flis
authors.forename: Susanna K
authors.initials: SK
authors.lastname: Remold
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D000330:Aedes / Q000254:growth & development / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D005260:Female; D006458:Hemolymph / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007814:Larva / Q000254:growth & development / Q000502:physiology; D016014:Linear Models; D008297:Male; D044969:Ochlerotatus / Q000254:growth & development / Q000502:physiology*; D012737:Sex Factors; D012965:Sodium Chloride / Q000032:analysis; D013045:Species Specificity
chemical_list: D012965:Sodium Chloride