Cretaceous Scaphopoda (Mollusca) of Australia and their palaeobiogeographic significance

The Cretaceous scaphopod (molluscan) fauna of mainland Australia is charact erised by a rather depauperate and poorly known assemblage of five species: dentaliids Dentalium (Dentalium) n. sp. A (probably Aptian), Dentalium (De ntalium) n. sp. B (Cenomanian), and Dentalium (Dentalium) n. sp. C (Maastri chtian); fustiariid Fustiaria wollumbillaensis (Etheridge, Jr., 1892) (Late Aptian-Albian?); and laevidentaliid Laevidentalium cretaustralium n, sp. ( Late Albian). Each species is endemic to either the Great Artesian Basin or Carnarvon Basin of Australia. A probable sixth species is recorded from Ce nomanian deposits of Bathurst Island, but the affinity of this taxon is unc ertain. In some shell beds of the Allaru Formation, scaphopods dominate the preserved macrobenthos. Although at species level the fauna is endemic, st rongly cosmopolitan genus level links of the scaphopods mirror that of othe r groups of molluscs (bivalves, gastropods, cephalopods), indicating deriva tion from evolutionary separation from pre-existing widespread Mesozoic sto cks which experienced gradual range restriction during the late Mesozoic. A systematic checklist of all Cretaceous Austral scaphopods is provided to i lluminate the palaeobiogeographic history of this little known molluscan gr oup.