Anopheles stephensi (Diptera: Culicidae): changes in male mating competence and reproductive system morphology associated with aging and mating.

Abstract

Laboratory observations on the mating behavior of the Khano-Harni ( KH ) strain of Anopheles stephensi indicated that females and males become sexually mature by their 2nd night of life. Some females (10%, n = 67) mated on their night of emergence when crossed with 3-day-old males. At 28–30 °C maximum male mating activity occurred between 3 and 7 days of age. Comparisons between the percentage of laboratoryadapted KH females inseminated by KH males and wild-caught ( WC ) males indicated that little change in group mating occurs during colonization, while the ability of males to mate singly improves with laboratory selection. Dissections of KH males of known age and mating history indicated that the number of spermatocysts decrease and the proportion of the testes occupied by the sperm reservoir increases with age, while the quantity of spermatozoa present in the sperm reservoir and postgonadal system and the degree of repleteness of the male accessory glands with secretory material decreases with successive matings. The male reproductive system was found to rejuvenate after mating, with the replenishment of male accessory gland substance in the accessory glands and spermatozoa in the sperm reservoir and postgonadal system. Males that multiplymated during an abbreviated interval took longer to rejuvenate their reproductive systems than did males mating once. Morphological changes associated with age and mating were used to develop a method to determine age and the reproductive history of male An. stephensi