New species of Banksieaeformis and a Banksia 'cone' (Proteaceae) from the tertiary of central Australia

Abstract

Silicified leaf impressions attributed to the tribe Banksieae (Proteaceae) are reported from a new Tertiary macroflora from near Glen Helen, Northern Territory and from the Miocene Stuart Creek macroflora, northern South Australia. The fossil leaf material is described and placed in Banksieaeformis Hill & Christophel. Banksieaeformis serratus sp. nov. is very similar in gross morphology to the extant Banksia baueri R.Br. and B. serrata L.f. and is therefore representative of a leaf type in Banksia that is widespread geographically and climatically within Australia and that is unknown in Dryandra or other genera of the Banksieae. The leaf material from Stuart Creek and Woomera represents the lobed leaf form typical of Paleogene macrofloras from southern Australia, but one species,B. langii sp. nov., is closely similar in gross form to Banksieaephyllum taylorii R.J.Carpenter, G.J.Jordan & R.S.Hill et al. from the Late Paleocene of New South Wales and similarly may be sclerophyllous. Also reported are impressions of Banksia infructescences, or ‘seed cones’, in Neogene sediments near Marree and Woomera, South Australia. These fossils demonstrate the presence of Banksiinae in central Australia in the mid-Tertiary, potentially indicating the former existence of linking corridors between now widely separated populations of Banksia.