Under insectary conditions the Sattoki laboratory strain of Anopheles culicifacies emerged during late afternoon and early evening. Mating occurred rhythmically, primarily during the simulated dusk with a few matings occurring during dawn. Females were sexually mature by the dusk of their 2nd day of life, whereas males required an extra day to attain maximum maturity. Maximum male mating activity on day 3 was followed by a rest interval, after which mating activity was again renewed on day 7.