Answer:
The platypus is sometimes known as a "duck-billed platypus", but this is a misnomer, as its bill serve a function quite different to that of a duck. Its bill is quite a distinctive feature, and is crucial to the platypus finding food, as it is equipped with sensitive electroreceptors.
Despite popular opinion, the platypus is not a mix of beaver, otter and duck. This is a myth.
A platypus is a monotreme, i.e. an egg-laying mammal. It is one of just two egg-laying mammals, the other being the echidna. It has dense, waterproof fur and a thick, beaver-like tail, but that is its only resemblance to a beaver. Its tail has fur whereas a beaver's tail does not. The thickness of a platypus's tail is indicative of its health and how well nourished it is.
It has short legs with webbed feet, and is well-equipped to hunt in the water, yet spends most of its time on land. Each foot has five toes with sharp claws, as it digs a burrow in the riverbank for shelter. When swimming, a membranous "web" extends between the toes.
The male platypus has a venomous spur on its hind leg, which cannot kill a healthy adult human but can cause extreme pain. Both male and female platypuses are born with spurs, but the females' spurs fall off within the first year, whereas a male will have his through life.
The platypus is shy and nocturnal, active mostly at dawn and dusk. It hunts for food underwater, using its duck-like bill, which is equipped with extremely sensitive electroreceptors to find food such as insect larvae, snails, worms, small fish, and crustaceans. It can remain underwater for between one and five minutes.
The platypus is found in freshwater creeks and rivers in eastern Australia, from sub-alpine regions north to the sub-tropical zone.