Mammals
Marine mammals (Class Mammalia) are those which have adapted to live in, or rely exclusively on, the marine environment. In South Australia, the only marine mammals of note are the Pinnipeds (seals and sea lions), who have adapted to coastal environments and Cetaceans (dolphins and whales), who are exclusively aquatic, unable to survive on land.
Dolphins and Whales (Suborder Cetacea)
Seals and Sea Lions (Suborder Pinnipedia)