Résumé
In the Devonian, plants evolved modern vegetative and reproductive structures, leading to significant systematic diversification and the establishment of modern lineages. However, the most recent diversity analyses show significant paleogeographic biases in the fossil record, particularly with regard to the Gondwana paleocontinent 1 . This incompleteness of the data leads to an incomplete and perhaps distorted view of the patterns of this diversification. The study of the Gooloogong plant assemblage presented for this conference is a new contribution to the study of the Upper Devonian floras of Australia. The material comes from plant beds of the Gooloogong member of the Hunter Formation in central New South Wales 2 . It consists of specimens from the Ritchie & Jones collection at the Australian Museum in Sydney and fossils collected during a mission in 2004 in which Philippe Gerrienne took part. The fossils are fragmentary and preserved in the form of casts, adpressions and permineralizations. The assemblage features an association of Lycopsida represented by Leptophloeum rhombicum, Cladoxylopsida represented by an axis assigned to the genus Denglongia, and Archaeopteridales (Progymnospermopsida) represented by various vegetative remains including a leaf attributed to the species Archaeopteris macilenta. This association is characteristic of Frasnian levels in South China, confirming the age of the Gooloogong deposit 3,4 . In addition to being the first record of Denglongia outside China and one of the earliest evidences of cladoxylopsids in Australia, this association shows the existence of floristic exchanges with South China.