The distribution of cell types in the malpighian tubules of Aedes taeniorhynchus (Wiedemann) (Diptera : Culicidae)

Abstract

We have developed a histological technique that allows all of the cells in the malpighian tubules of Aedes taeniorhynchus (Diptera : Culicidae) and a few other mosquitoes to be counted and identified to cell type. We used this technique to examine the number and distribution of primary and stellate cells. Tubules, taken from the 4th instar larvae, pupae, adult males, and adult females, were examined. The mosquitoes were reared as larvae in either 10% or 100% seawater. In all cases examined, the total number of cells composing a tubule was somewhat variable, but no correlation between cell number and developmental stage, environmental salinity, or adult sex was observed. Under all conditions examined, stellate cells compose a fairly constant 16–18% of the total cell population of the tubule. Stellate cells were absent from the tubules in a region near the point of attachment to the midgut. Similar distribution ratios of primary and stellate cells were observed in the tubules of Aedes aegypti, Culex tansalis, and Culiseta inornata. The significance of these findings to a previously proposed tole for stèllate cells in ion transport is discussed.