Males depleted for saturn show reduced sperm production and inefficient sperm storage. (A) Mature, individualized sperm present in the seminal vesicle (SV) of saturn knockdown (KD, n = 20 flies) and control (cont, n = 10) males. Each data point represents the average number of sperm per SV for one male. (B) Sperm present in the female uterus 30 min ASM with saturn KD (n = 15) or control (n = 13) males. (C) Sperm present in the female seminal receptacle (SR) 1 h ASM with saturn KD (n = 15) or control (n = 13) males. (D) Sperm present in the SR 2 hours ASM with saturn KD (n = 13) or control (n = 15) males. In all panels, KD values are significantly less than controls (two-sample t-tests, all P < 0.0001).