AEDES-AEGYPTI - SENSILLA TRICHODEA AND STIMULUS-CONDUCTING STRUCTURES

Much of the morphology of the olfactory sensilla on the antennae of th e mosquito Aedes aegypti (L.) has been described, however little is kn own about the fate of odour molecules once they have been adsorbed ont o the surfaces of sensilla. A stimulus-conducting system of pores, por e kettles, and pore tubules has been described for the sensilla tricho dea (olfactory hairs) of several insects but not mosquitoes. Scanning electron microscopy was used to identify the s. trichodea of Ae. aegyp ti and to attempt visualization of their pore openings. Chemical fixat ion, cryopreparation, freeze drying, and negative staining, with high resolution transmission electron microscopy (TEM), were used to locate putative stimulus-conducting structures associated with the pores. TE M sections using Dalton's fixative or freeze drying showed pores and p ore tubules, whereas pore tubules were poorly preserved in cryoprepare d sections. The putative stimulus-conducting structures were clearly d emonstrated by negative staining of whole sensilla which was quick and easy. The current hypothesis of olfactory stimulus conduction is exte nded to include Ae. aegypti.