[The morphofunctional changes in the ovarioles of blood-sucking mosquitoes (Diptera, Culicidae) during oogenesis. 3. Anomalous forms of the ovarioles].

The authors describe blood-sucking mosquito ovarioles in which the development of germarium or follicles is abnormal and asynchronous with the gonotrophic cycles. The following morphologic variants of abnormal ovarioles may be distinguished: club-shaped without follicles; multichamber with several follicles; miniature with a diminished follicle; with atypical oocyte number in a follicle. The ovariole sterility may be due to cessation of germarium functioning (club-shaped ovarioles consisting of flat mesodermal cells), or to rapid or slow, as against that in the reproductive cycle, rate of follicle detachment from germarium, followed by follicle degeneration (ovarioles with aberrant dilatations). After 3-4 reproductive cycles there is a trend to localization of abnormal ovarioles near large tracheas in sites depleted for tracheoles. This is particularly typical of Anopheles messeae. The authors come to a conclusion that oocyte and follicle elimination is a normal phenomenon is nature, and that their abnormal development is explained by the effects of different factors.