Taxodiaceous Macrofossils from Tertiary and Quaternary Sediments in Tasmania

Abstract

Taxodiaceous macrofossils are described from several Tertiary and Quaternary sedimentary environments in Tasmania. One new species of Athrotaxis is described, based on vegetative remains and an ovuliferous cone. This species, A. mesibovii, occurs in three sites of Oligocene–Early Miocene age and most closely resembles the extant A. selaginoides in its large leaf size. Another fossil species, Athrotaxis rhomboidea, was originally assigned to the genus Mesibovia in the Podocarpaceae, but examination of ovuliferous cones requires that it be transferred to Athrotaxis. This species was also present in several sites during the Oligocene–Early Miocene. Vegetative remains and ovuliferous cones from the Oligocene Little Rapid River site are assigned to a new species of the extinct genus Austrosequoia, which was previously only known from the Cretaceous of Queensland. The similarity of Austrosequoia to Sequoia is noted, and the possibility that the two are congeneric is emphasised.