The Eocene flora of the Anglesea Locality, Victoria

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Abstract
Megafossils from six discrete clay lenses at two sites in the Alcoa Anglesea open-cut coal mine were scored for frequency of 19 leaf types to determine if the observed distinctness of the floras was real. An analysis of the pollen/spore assemblages from the six lenses and from a vertical transect taken at the second site was also undertaken (a) to confirm the age of the deposit, (b) to determine if the microfloras of the lenses were distinctive and (c) to compare mega- and microcomponents of the flora. This analysis confirmed placement of the clay lenses at the onset of the Middle Nothofagidites asperus Zone of the late Middle Eocene age. No significant differences in the microfloras of the six lenses were observed. Accessory analysis of the geology of the locality revealed a sedimentation pattern consistent with a meandering stream system, perhaps containing local lacustrine elements. All megafossil taxa identifiable to family or lower (except Lauraceae) were found to be present in the combined pollen/spore flora, but comparative frequencies were not consistent. Extant vegetation from Noah Creek in N.E. Queensland was examined and considered to provide a possible model for the Anglesea fossil flora. Along one section of Noah Creek a mosaic of physiognomic and floristic elements occurs, in an area of similar size to the Anglesea deposit. This same flora contains many of the taxa (or most nearly related taxa) identified thus far at the Anglesea Locality, including some rare associations involving Gymnostoma, Orites and members of the Musgraveinae. Further tests for the model are proposed.