The eggs of Saint Andrew’s cross toadlets are laid in small pools of rain water held in tree holes, known as phytothelms (3). Females can lay as many as 26 ivory coloured eggs, although studies of captive individuals have recorded an average of 16 eggs, laid two or three times each year (3). After hatching in this small body of water, the grey tadpoles take 30 to 40 days to develop into an adult toad (5). The exact time taken depends on the temperature of the water; in warmer water the tadpoles will develop more quickly than those in cooler water (5).
During this fascinating period of metamorphosis, Saint Andrew’s cross toadlet does not need to eat at all, as amazingly it hatches from the egg with all the energy it requires as a tadpole in its abdominal yolk sac (3). The provision by the yolk sac of all the necessary energy for growth, also known as endotrophic development, is found in very few frogs and toads (3).