4 SPECIES OF METACERATODUS (OSTEICHTHYES, DIPNOI, FAMILY CERATODONTIDAE) FROM AUSTRALIAN MESOZOIC AND CENOZOIC DEPOSITS

The ceratodont lungfish Metaceratodus wollastoni is described from new material from central and southern Australia, and three additional sp ecies, Metaceratodus ellioti, Metaceratodus bonei, and Metaceratodus p almeri are included in the genus. M. ellioti and M. bonei are new spec ies, and M. palmeri, originally described as Ceratodus palmeri, has be en reassigned. The current determinations of species are based on morp hological characters. M. wollastoni is found in Lower and Upper Cretac eous deposits in southeast and central Australia. M. ellioti is confin ed to the Upper Cretaceous of southeast and central Australia. M. bone i is found in the Namba and Etadunna formations in central Australia, late Oligocene to middle Miocene in age, as well as a single record fr om a possible Pleistocene deposit. M. palmeri comes from strata belong ing to the Pliocene and Pleistocene of eastern Australia. At least one species of Metaceratodus also occurs in the Lower Cretaceous Coli-Tor o Formation of South America.