Endosymbiotic relationship between a rickettsia-like microorganism and the male germ-cells of Culex tigripes.

The male mosquitoes of the species Culex tigripes possess endosymbionts localized in the cytoplasm of the germ-cells. The somatic cells of the testis do not exhibit this particularity. The spermatogonia, spermatocytes and spermatids all possess a few symbionts. They are eliminated in the residual body at the end of spermiogenesis when the spermatozoon matures. They are absent from the seminal vesicles. A few spermatocytes and spermatids show a proliferation of the endosymbionts. This seems to be associated with an abnormal spermiogenesis. These symbionts are comparable to the Wolbachia described in two other species of mosquitoes: Culex pipiens and Aedes scutellaris.