The female and male internal genitalia, the oogenesis, and the spermatogenesis of the privet mite Brevipa/pus obovatus Donnadieu have been described. The female reproductive organs consist of an ovary, an oviduct, a vagina and a receptaculum seminis. The oogonial divisions give rise to groups of four primary oocytes which differentiate into a nurse cell syncytium and a growing oocyte during diffuse stage. The growing oocyte develops outside the ovary. The male reproductive organs consist of a pair of testes, a pair of vesiculae seminalis, a sperm pump, a ductus ejaculatorius, and an aedeagus. The spermatogonia differentiate directly into spermatids. Spermiogenesis gives rise to cup-shaped spermatozoa and, in a few males only, also to spherical spermatozoa. Sperm production is low. The males are able to copulate but insemination does not take place. The mites reproduce by automictic parthenogenesis which is made possible by an additional premeiotic doubling of the chromosomes.