Examination and dissection of museum specimens, combined with observations of freeranging and captive snakes, provided original data on morphology, sexual dimorphism, feeding habits, and reproductive biology of shieldnose snakes (Aspidelaps scutatus) from southern Africa. These small (to 60 cm snout-vent length) stockily-built snakes are nocturnal, and often fossorial. Females mature at larger sizes than males, and attain larger maximum sizes. At the same body length, males have longer tails, and longer and wider heads, than do conspecific females. The sex divergence in head sizes and shapes may be related to dietary differences between the sexes: males contained a significantly higher proportion of anuran prey, and fewer snakes and mammals, than did conspecific females. However, sample sizes for this comparison were small. Reproduction is strongly seasonal, with mating in spring (October), oviposition in midsummer (December-January), and hatching in autumn (March). Females laid 4 to 10 eggs (mean = 7.9), with clutch size, egg size, and Relative Clutch Mass (RCM) independent of maternal body size. Offspring averaged 16 cm (5 g) and RCM averaged 0.48.