Tertiary gymnosperms from Tasmania: Araucariaceae

Abstract

Three new species of the Araucariaceae are described from leaf remains, Araucaria readiae from the Early Eocene Regatta Point flora, A. hastiensis from the Middle-Late Eocene Hasties flora, and Agathis tasmanica from the Early Oligocene-Early Miocene Little Rapid River flora. Additionally, emended diagnoses are presented for Araucarioides linearis and A. annulata. A. readiae is the first organically preserved species in the section Eutacta described from Tasmania, A. hastiensis is the first record of a species not in section Eutacta in Tasmania, and A. tasmanica is the first record of Agathis in Tasmania. These species, along with other records from south-eastern Australia indicate the presence of a high diversity of araucarian species in the region in the Early-Middle Tertiary, although no species survive there today. Climatic change and competition from angiosperms may have led to their demise in that region.