Oloigocene leaves of Epacidaceae from Little Rapid River, Tasmania, and the identification of fossil Epacidaceae leaves

Abstract

The leaves of most Epacridaceae have distinctive combinations of shape, venation and cuticular morphology. Some groups of genera, but few genera or species, also have distinctive combinations of leaf traits. Two new genera, Epacriphyllum and Richeaphyllum, are proposed for fossil leaves which can be clearly attributed to tribe Epacrideae and subfamily Richeoideae respectively, but cannot be assigned to extant genera due to lack of information. Two new species of Epacriphyllum and one of Richeaphyllum are proposed from Oligocene sediments at Little Rapid River, western Tasmania. Leaves which are probably of the tribe Styphelieae also occur in these sediments. These are the earliest macrofossil records of the family, and confirm that two large phylogenetic groups within the family had differentiated by this time. A key to groups of epacridaceous genera is given to assist the identification of fossil leaves.