A nocturnal monotreme mammal, the only member of the family Ornithorhynchidae native to eastern Australia and Tasmania that is highly adapted to an aquatic life. Its digits are webbed, a spur on the inside of each hind leg carries venom, the tail resembles that of a beaver, and the snout is covered with thick skin resembling a duck’s bill. The platypus feeds on aquatic invertebrates and in spring lays one–three eggs in a nest constructed in a burrow close to water.