Oligocene leaves, fruit and flowers of the Cunoniaceae from Cethana, Tasmania

Abstract

At least five species in five genera from the Cunoniaceae occur in the Oligocene Cethana deposit. A Callicoma leaf and infructescence are indistinguishable from those of C. serratifolia, the only extant species, and are therefore assigned to that species. Schizonzeria tasmaniensis sp. nov. and Acsmithia grandiflora sp. nov. are represented by flowers and Vesselowskya aff. rubifolia by a leaf or leaflet. Compound leaves of Weinmailrlia/Cunonia so far collected lack cuticular preservation, but their distinctive morphology enables confident placement in this group. Since these genera are only segregable on reproductive features a new genus, Weinmanniaphyllum, is proposed. The fossil data confirm that eastern Australia has been a centre of diversity for the family since at least the Early Tertiary. Modem representatives of the fossil taxa now occur in New South Wales, Queensland, New Guinea, Pacific Islands and South and Central America. None occurs in Tasmania. The evidence is further support for the presence of floristically diverse, microthermal rainforests and disturbed oligotrophic habitats in the Early Tertiary of Tasmania.