Aporosaura anchietae maintained continuous reproduction over a 24-month period during which rainfall, prey diversity and prey abundance changed greatly. Lizards responded rapidly to improved environmental conditions by accumulating large quantities of fat. Females utilized the fat body to produce various clutches of one or two large eggs over a prolonged period. The annual egg production declined by approximately 50 % when rainfall decreased from 125 mm to 12 mm. The average clutch was 1.52 and 1.19 eggs in the wet and dry years, respectively. Territorial males used stored energy to offset caloric imbalances caused by restricted foraging. The advantages of small female body size and a large hatchling are discussed in relation to the Namib dune habitat. Environmental conditions favouring aseasonal reproduction in extreme deserts are described, and aspects of the reproductive behaviour and polygynous breeding system are related to the dune ecology.