The Female Reproductive Cycle of the Lizard Cordylus p. polyzonus (Sauria: Cordylidae) in the Southwestern Cape Province, South Africa

Abstract

ABSTRAcr. - The female reproductive cycle of the viviparous lizard Cordylus p. polyzonus in the southwestern Cape Province, South Africa, is described. A winter/spring vitellogenic period (June-October) with ovulation occurring in late spring (November) was exhibited. Embryonic development occurred throughout summer and early autumn with parturition in April. Females produced 1-3 embryos and clutch size was positively correlated with female body size. During pregnancy the ovaries contained corpora lutea, the quantity corresponding with the number of developing embryos. Ovarian follicles remained small and translucent during pregnancy. In the post-partum months of April and May, ovarian follicles were undeveloped and the presence of corpora albicantia was characteristic. Oviductal growth was initiated just prior to ovulation and oviducts were hypertrophied throughout pregnancy. Liver and fat body masses peaked during late vitellogenesis and both variables were positively correlated with the ovarian cycle. The onset of vitellogenesis coincided with declining environmental temperatures and photoperiod.