SOUTHERN AUSTRALIAN ENDEMIC AND SEMI-ENDEMIC FORAMINIFERA - A PRELIMINARY-REPORT

The Cenozoic in southern Australia contains many foraminifera endemic to the region in neritic (intermediate- to shallow-water) facies. They were mostly epifaunal and inhabited waters to some 300 m deep. This e ndemism is first obvious in the later Eocene when Maslinella, Crespini na and Wadella, among others, evolved. More than half of the Eocene en demic species disappeared in the Eocene or Oligocene. There followed i n the Oligocene the evolution of such species as Parrellina imperatrix and Astrononion centroplax. The Miocene was a time of slightly reduce d endemism and is characterized by migration into the region of many l arger (sub)tropical taxa such as Lepidocyclina and Cycloclypeus. The l ong-ranging genus Notorotalia emerged about 50 Ma ago and is still com mon in modern southern mid-latitude waters. The youngest common extant species which made their first appearance in the Pliocene-Quaternary include Dircorbis dimidiatus and Parredicta porifera, both with a test up to 1.5 mm in diameter. A similar pattern has been recorded in New Zealand. Four phases of endemism can be recognized: later Eocene, Olig ocene, Miocene and Pliocene-Quaternary. It appears that the four phase s were all stimulated in response to major marine transgressions, resp ectively the Wilson Bluff (=Khirthar), Aldingan, Clifton-Longfordian a nd Hallet Cove-Glanville transgressions. Probably they signal four imp ortant stages in the transformation of water masses along the southern continental margin.