Occurrence of Casuarina Megafossils in the Tertiary of South-Eastern Australia

Abstract

Casuarina megafossils are reported from three Eocene localities and one Miocene locality in south-eastern Australia. On both vegetative and reproductive characters all Eocene material shows clear affinities with the extant Division Gymnostomae. The affinities of the Miocene material are less clear. However, a shift in frequency from Gymnostomae to Cryptostomae on the Australian continent during the Tertiary is suggested. Such a change is consistent with the northward movement and the climatic deterioration which occurred on the Australian continental plate during that time.