Reproductive cycles of the snakesPsammophis crucifer, P. leightoni trinasalisandP. notostictus(Serpentes: Colubridae) in the Orange Free State, South Africa

FLEMMING, A.F. 1994. Reproductive cycles of the snakes Psammophis crucifer, P. leightoni trinasalis and P. notostictus (Serpentes: Colubridae) in the Orange Free State, South Africa. J. Herpetol. Assoc. Afr. 43: 19–27. The male and female reproductive cycles of the colubrid snakes Psammophis crucifer, P. leightoni trinasalis and P. notostictus are described. Males of all three species exhibited basic prenuptial spermatogenic cycles. Onset of spermatogenesis during summer to autumn coincided with decreasing ambient temperature, photoperiod and rainfall. Peak spermatogenesis in P. crucifer occurred from autumn to summer, while in P. l. trinasalis and P. notostictus it occurred during winter to summer. Females of all three species exhibited vitellogenesis and ovulation during spring. Onset of vitellogenesis may occur as early as winter and coincided with increasing ambient temperature, photoperiod and rainfall. Oviposition occurred from spring to early summer. P. crucifer females produced 4–13, P. l. trinasalis females 1–8 and P. notostictus females 3–8 eggs respectively. In all species onset of gonadal activity between sexes was asynchronous, while later stages of gonadal activity were synchronous, with spermiogenesis and ovulation occurring simultaneously.