Reproduction in the lizard Mabuya heathi (Scincidae): a commentary on viviparity in new world Mabuya

Abstract

The tropical Brazilian skink M. heathi is viviparous, producing ova which increase in wet mass by 53,800% and in dry mass by 38,400% during gestation. Ovulation occurs during Oct.-Jan., rapid growth in embryos takes place during June-Oct., and parturition occurs in Sept.-Nov., between 9 and 12 mo. after ovulation. Female and male reproduction is cyclic and is synchronous between the sexes. Brood size is 2-9 (.hivin.x = 5.0 .+-. 0.1) and is significantly correlated to female size. Fat bodies of females are largest when embryos are small, and decrease in mass as embryos increase in size. Testes in males are largest during Sept.-Feb., associated with a decrease in fat body size. M. heathi is the 2nd species of lizard in the caatinga herpetofauna shown to be strongly cyclical in reproduction and to reproduce only once per year.