Greenwood, D.R.Conran, J.G.2025-03-112025-03-112025Historical Biology: an international journal of paleobiology, 2025; 37(7):1601-16130891-29630891-2963https://hdl.handle.net/2440/143833Published online: 25 Sep 2024Fossil pinnate palm leaves (Arecaceae, subfam. Arecoideae) are described from the Eocene or Miocene Island Lagoon fossil site near Woomera in the arid zone of South Australia. These leaves are described as a new species, Phoenicites insula-lacuna and shown to share morphological similarities to the extant genus Archontophoenix (subtr. Archontophoenicinae), endemic to eastern Australia. This fossil record constitutes a significant temporal and geographic range extension for Archontophoenicinae and likely Archontophoenix. The presence in Australia of Archontophoenicinae as early as the Eocene or more likely Miocene, is in accordance with molecular analyses that propose dispersal of this clade into Australia from New Guinea, with subsequent dispersal from Australia to New Caledonia and divergence of the Archontophoenix and Chambeyronia lineages during this interval of time. Previously reported co-occurring myrtaceous woody fruits from Island Lagoon and proximal-coeval silcrete floras previously referred to Angophora, Callistemon, Eucalyptus, Melaleuca and fossils of other sclerophyllous taxa such as Banksia are consistent with this palm being part of a landscape mosaic with riparian rainforest that included mesic plants growing within wider sclerophyllous forest or woodland vegetation comparable to the eastern coastal zone of modern-day Australia and the modern range of Archontophoenix.en© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), whichpermits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way. The terms onwhich this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent.Palm; Arecaceae; paleogene–neogene; Australia; Archontophoenix; silcrete macroflorasJournal article10.1080/08912963.2024.2403591712068Conran, J.G. [0000-0003-2268-2703] [0009-0002-8116-4527]