The vectorial capacity of
Aedes aegypti
is directly influenced by its high reproductive output. Nevertheless, females
are restricted to a single mating event, sufficient to acquire enough sperm to fertilize a lifetime supply of eggs.
How
Ae. aegypti is able to maintain viable spermatozoa remains a mystery. Male spermatozoa are stored within
either of two spermathecae that in
Ae. aegypti consist of one large and two smaller organs each. In addition, each
organ is divided into reservoir, duct and glandular portions. Many aspects of the morphology of the spermatheca
in virgin and inseminated
Ae. aegypti were investigated here using a combination of light, confocal, electron and
scanning microscopes, as well as histochemistry. The abundance of mitochondria and microvilli in spermathecal
gland cells is suggestive of a secretory role and results obtained from periodic acid Schiff assays of cell apexes and
lumens indicate that gland cells produce and secrete neutral polysaccharides probably related to maintenance of
spermatozoa. These new data contribute to our understanding of gamete maintenance in the spermathecae of
Ae.
aegypti and to an improved general understanding of mosquito reproductive biology.
