Discovery of vertebrates in "Calcaires de Rona" (Thanetian or Spanacian), Transylvania, Romania: Oldest known Cenozoic mammals from Eastern Europe

The new continental microvertebrate localities reported here from the "Calc aires de Rona", NW Transylvania, Romania, yield the oldest mammals from Eas tern Europe. An unsolved Thanetian-Sparnacian age is indicated by a previou sly unreported specific association of mixed biostratigraphic affinities. T he occurrence of a rodent postdates the MP6 reference-fauna of Cernay, but does not exclude an age correlative to the North-American Clarkforkian. The charophytes, the chelonians, and the mammals from the Transylvanian sites are of typical European affinities and are the first data for a significant Eastern extension of the European biotic province at the Paleocene-Eocene transition. A new chelonian is referred to the family Dortokidae, previousl y known only in the Cretaceous of SW Europe. The still poorly documented ma mmals include multituberculates and primitive eutherians ("insectivores", c ondylarths, and an undeterminate rodent). These new Transylvanian localitie s add new important data to the knowledge of the evolution of early Cenozoi c mammals in Europe and their paleobiogeography.